ALBERT

Description: Publication date: Available online 9 July 2016 Source: Geodesy and Geodynamics Author(s): Ruisha Li, Xi Zhang, Shouwen Gong, Hongtao Tang, Peng Jia The equation for determining cross-fault representative value is calculated based on hanging wall and foot wall reference level surfaces. The cross-fault data reliability are analyzed base on the stability of reference datum and observation points, thereby facilitating plotting of the representative value curves after removing interference. The spatial and temporal characteristics of fault deformation abnormalities before the 2016 Menyuan M s6.4 earthquake, as well as the fault-movement characteristics reflected by representative value, are summarized. The results show that many site trends had changed 1–3 years before the Menyuan M s6.4 earthquake in the Qilian Fault, reflecting certain background abnormalities. The short-term abnormalities centrally had appeared in the 6 months to 1 year period before the earthquake near and in the neighborhood of the source region, demonstrating a significantly increased number of short-term abnormalities. Many sites near and in the neighborhood of the source region had strengthened inverse activities or had changed from positive to inverse activities in the most recent 2–3 years, which reflect stress-field enhancements or adjustment features.

Description: Publication date: Available online 19 July 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Aref al-Swaidani, Ibrahim Hammoud, Ayman Meziab Clayey soils in Syria cover a total area of more than 20,000 km 2 of the country, most of which are located in the southwestern region. In many places of the country, the clayey soils caused severe damage to infrastructures. Extensive studies have been carried out on the stabilization of clayey soils using lime. Syria is rich in both lime and natural pozzolana. However, few works have been conducted to investigate the influence of adding natural pozzolana on the geotechnical properties of lime-treated clayey soils. The aim of this paper is to understand the effect of adding natural pozzolana on some geotechnical properties of lime-stabilized clayey soils. Natural pozzolana and lime are added to soil within the range of 0%−20% and 0%−8%, respectively. Consistency, compaction, California bearing ratio (CBR) and linear shrinkage properties are particularly investigated. The test results show that the investigated properties of lime-treated clayey soils can be considerably enhanced when the natural pozzolana is added as a stabilizing agent. Analysis results of scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) show significant changes in the microstructure of the treated clayey soil. A better flocculation of clayey particles and further formation of cementing materials in the natural pozzolana-lime-treated clayey soil are clearly observed.

Description: Publication date: Available online 15 July 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Sadok Benmebarek, Samir Attallaoui, Naïma Benmebarek Back-to-back mechanically stabilized earth walls (BBMSEWs) are encountered in bridge approaches, ramp ways, rockfall protection systems, earth dams, levees and noise barriers. However, available design guidelines for BBMSEWs are limited and not applicable to numerical modeling when back-to-back walls interact with each other. The objective of this paper is to investigate, using PLAXIS code, the effects of the reduction in the distance between BBMSEW, the reinforcement length, the quality of backfill material and the connection of reinforcements in the middle, when the back-to-back walls are close. The results indicate that each of the BBMSEWs behaves independently if the width of the embankment between mechanically stabilized earth walls is greater than that of the active zone. This is in good agreement with the result of FHWA design guideline. However, the results show that the FHWA design guideline underestimates the lateral earth pressure when back-to-back walls interact with each other. Moreover, for closer BBMSEWs, FHWA design guideline strongly overestimates the maximum tensile force in the reinforcement. The investigation of the quality of backfill material shows that the minor increase in embankment cohesion can lead to significant reductions in both the lateral earth pressure and the maximum tensile force in geosynthetic. When the distance between the two earth walls is close to zero, the connection of reinforcement between back-to-back walls significantly improves the factor of safety.

Description: Publication date: Available online 28 June 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Hossein Mola-Abasi, Issa Shooshpasha It is well known that the cemented sand is one of economic and environmental topics in soil stabilization. In this instance, a blend of sand, cement and other materials such as fiber, glass, nanoparticle and zeolite can be commercially available and effectively used in soil stabilization in road construction. However, the influence and effectiveness of zeolite on the properties of cemented sand systems have not been completely explored. In this study, based on an experimental program, the effects of zeolite on the characteristics of cemented sands are investigated. Stabilizing agent includes Portland cement of type II and zeolite. Results show the improvements of unconfined compressive strength (UCS) and failure properties of cemented sand when the cement is replaced by zeolite at an optimum proportion of 30% after 28 days. The rate of strength improvement is approximately between 20% and 78%. The efficiency of using zeolite increases with the increases in cement amount and porosity. Finally, a power function of void-cement ratio and zeolite content is demonstrated to be an appropriate method to assess UCS of zeolite-cemented mixtures.

Description: Publication date: Available online 28 June 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Atsushi Sainoki, Hani S. Mitri Fault-slip taking place in underground mines occasionally causes severe damage to mine openings as a result of strong ground motion induced by seismic waves arising from fault-slip. It is indicated from previous studies that intense seismic waves could be generated with the shock unloading of fault surface asperities during fault-slip. This study investigates the shock unloading with numerical simulation. A three-dimensional (3D) numerical model with idealized asperities is constructed with the help of discrete element code 3DEC. The idealization is conducted to particularly focus on simulating the shock unloading that previous numerical models, which replicate asperity degradation and crack development during the shear behavior of a joint surface in previous studies, fail to capture and simulate. With the numerical model, static and dynamic analyses are carried out to simulate unloading of asperities in the course of fault-slip. The results obtained from the dynamic analysis show that gradual stress release takes place around the center of the asperity tip at a rate of 45 MPa/ms for the base case, while an instantaneous stress release greater than 80 MPa occurs near the periphery of the asperity tip when the contact between the upper and lower asperities is lost. The instantaneous stress release becomes more intense in the vicinity of the asperity tip, causing tensile stress more than 20 MPa. It is deduced that the tensile stress could further increase if the numerical model is discretized more densely and analysis is carried out under stress conditions at a great depth. A model parametric study shows that in-situ stress state has a significant influence on the magnitude of the generated tensile stress. The results imply that the rapid stress release generating extremely high tensile stress on the asperity tip can cause intense seismic waves when it occurs at a great depth.

Description: Publication date: Available online 18 June 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Morteza Esmaeili, Hamid Khajehei Deep mixed column (DMC) is known as one of the effective methods for stabilizing the natural earth beneath road or railway embankments to control stability and settlements under traffic loads. The load distribution mechanism of embankment overlying on loose subgrades stabilized with DMCs considerably depends on the columns' mechanical and geometrical specifications. The present study uses the laboratory investigation to understand the behavior of embankments lying on loose sandy subgrade in three different conditions: (1) subgrade without reinforcement, (2) subgrade reinforced with DMCs in a triangular pattern and horizontal plan, and (3) subgrade reinforced with DMCs in a square pattern and horizontal plan. For this purpose, by adopting the scale factor of 1:10, a reference embankment with 20 cm height, 250 cm length, and 93% maximum dry density achieved in standard Proctor compaction test was constructed over a 70 cm thick loose sandy bed with the relative density of 50% in a loading chamber, and its load-displacement behavior was evaluated until the failure occurred. In the next two tests, DMCs (with 10 cm diameter, 40 cm length, and 25 cm center-to-center spacing) were placed in groups in two different patterns (square and triangular) in the same sandy bed beneath the embankment and, consequently, the embankments were constructed over the reinforced subgrades and gradually loaded until the failure happened. In all the three tests, the load-displacement behaviors of the embankment and the selected DMCs were instrumented for monitoring purpose. The obtained results implied 64% increase in failure load and 40% decrease in embankment crest settlement when using the square pattern of DMCs compared with those of the reference embankment, while these values were 63% and 12%, respectively, for DMCs in triangular pattern. This confirmed generally better performance of DMCs with a triangular pattern.

Description: Publication date: Available online 15 July 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Brian G. Sexton, Bryan A. McCabe, Minna Karstunen, Nallathamby Sivasithamparam The recently developed elasto-viscoplastic Creep-SCLAY1S model has been used in conjunction with PLAXIS 2D to investigate the effectiveness of vibro-replacement in a creep-prone clay. The Creep-SCLAY1S model accounts for anisotropy, bonding, and destructuration, and uses the concept of a constant rate of viscoplastic multiplier to calculate creep strain rate. A comparison of settlement improvement factors with and without creep indicates that ‘total’ settlement improvement factors (primary plus creep) are lower than their ‘primary’ counterparts (primary settlement only). The lowest settlement improvement factors arise for analyses incorporating the effect of bonding and destructuration. Examination of the variations of vertical stress with time and depth has indicated that vertical stress is transferred from the soil to the column as the soil creeps. This results in additional column yielding. In addition, the radial and hoop stresses in the soil are lower for the ‘creep’ case. The reduced radial stresses lead to additional column bulging and hence more settlement, whereas the hoop stress reductions appear to be a secondary effect, caused by additional plastic deformation for the ‘creep’ case.

Description: Publication date: Available online 27 July 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Xudong Wang, Qinlin Guo, Shanlong Yang, Dexuan Zhang, Yanwu Wang arthen sites are widely distributed throughout China, and most of them belong to archaeological sites with significant values, which not only directly witness the origin, formation and development of Chinese civilization, but also possess important values for conservation and exhibition. Many researches and practices on their conservation and consolidation have been carried out; however, the consolidation effect is mainly judged by visual observation and expert evaluation. Scientific assessment of conservation and consolidation effects is a challenging issue. Many instruments in other fields cannot be directly applied to the conservation of cultural relics due to their peculiarity. In order to assess the effects of field conservation experiments, this paper tries to understand the consolidation effects at Liangzhu site using nondestructive or micro-damage methods, including thermo-physical parameters testing, infrared thermal imaging, high-density microelectrode resistivity testing, portable microscope observation, and hydrophilic and hydrophobic testing, and thereby explores the practicable methods for evaluating the properties of consolidation materials for earthen sites treatment.

Description: Publication date: Available online 25 June 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Hongwei Wang, Yaodong Jiang, Sheng Xue, Lingtao Mao, Zhinan Lin, Daixin Deng, Dengqiang Zhang This paper presents an investigation on the characteristics of overlying strata collapse and mining-induced pressure in fault-influenced zone by employing the physical modeling in consideration of fault structure. The precursory information of fault slip during the underground mining activities is studied as well. Based on the physical modeling, the optimization of roadway support design and the field verification in fault-influenced zone are conducted. Physical modeling results show that, due to the combined effect of mining activities and fault slip, the mining-induced pressure and the extent of damaged rock masses in the fault-influenced zone are greater than those in the uninfluenced zone. The sharp increase and the succeeding stabilization of stress or steady increase in displacement can be identified as the precursory information of fault slip. Considering the larger mining-induced pressure in the fault-influenced zone, the new support design utilizing cables is proposed. The optimization of roadway support design suggests that the cables can be anchored in the stable surrounding rocks and can effectively mobilize the load bearing capacity of the stable surrounding rocks. The field observation indicates that the roadway is in good condition with the optimized roadway support design.

Description: Publication date: Available online 18 June 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Aiqing Wu, Jimin Wang, Zhong Zhou, Shuling Huang, Xiuli Ding, Zhihong Dong, Yuting Zhang Based on the analyses of data obtained from the underground powerhouse at Jinping I hydropower station, a comprehensive review of engineering rock mechanics practice in the underground powerhouse is first conducted. The distribution of strata, lithology, and initial geo-stress, the excavation process and corresponding rock mass support measures, the deformation and failure characteristics of the surrounding rock mass, the stress characteristics of anchorage structures in the cavern complex, and numerical simulations of surrounding rock mass stability and anchor support performance are presented. The results indicate that the underground powerhouse of Jinping I hydropower station is characterized by high to extremely high geo-stresses during rock excavation. Excessive surrounding rock mass deformation and high stress of anchorage structures, surrounding rock mass unloading damage, and local cracking failure of surrounding rock masses, etc., are mainly caused by rock mass excavation. Deformations of surrounding rock masses and stresses in anchorage structures here are larger than those found elsewhere: 20% of extensometers in the main powerhouse record more than 50 mm with the maximum at around 250 mm observed in the downstream sidewall of the transformer hall. There are about 25% of the anchor bolts having recorded stresses of more than 200 MPa. Jinping I hydropower plant is the first to have an underground powerhouse construction conducted in host rocks under extremely high geo-stress conditions, with the ratio of rock mass strength to geo-stress of less than 2.0. The results can provide a reference to underground powerhouse construction in similar geological conditions.

Description: Publication date: Available online 3 August 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Shengwu Song, Xuemin Feng, Chenggang Liao, Dewen Cai, Zhongxu Liu, Yunhao Yang The Jinping I hydropower station is a huge water conservancy project consisting of the highest concrete arch dam to date in the world and a highly complex and large underground powerhouse cavern. It is located on the right bank with extremely high in-situ stress and a few discontinuities observed in surrounding rock masses. The problems of rock mass deformation and failure result in considerable challenges related to project design and construction and have raised a wide range of concerns in the fields of rock mechanics and engineering. During the excavation of underground caverns, high in-situ stress and relatively low rock mass strength in combination with large excavation dimensions lead to large deformation of the surrounding rock mass and support. Existing experiences in excavation and support cannot deal with the large deformation of rock mass effectively, and further studies are needed. In this paper, the geological conditions, layout of caverns, and design of excavation and support are first introduced, and then detailed analyses of deformation and failure characteristics of rocks are presented. Based on this, the mechanisms of deformation and failure are discussed, and the support adjustments for controlling rock large deformation and subsequent excavation procedures are proposed. Finally, the effectiveness of support and excavation adjustments to maintain the stability of the rock mass is verified. The measures for controlling the large deformation of surrounding rocks enrich the practical experiences related to the design and construction of large underground openings, and the construction of caverns in the Jinping I hydropower station provides a good case study of large-scale excavation in highly stressed ground with complex geological structures, as well as a reference case for research on rock mechanics.

Description: Publication date: Available online 19 July 2016 Source: Geodesy and Geodynamics Author(s): Yanbao Li, Weijun Gan, Yuebing Wang, Weitao Chen, Shiming Liang, Keliang Zhang, Yongqi Zhang On January 21, 2016, a strong earthquake with a magnitude of M s6.4 occurred at Menyuan, Qinghai Province of China. In almost the same region, there was another strong earthquake happened in 1986, with similar magnitude and focal mechanism. Based on comprehensive analysis of regional active faults, focal mechanism solutions, precise locations of aftershocks, as well as GPS crustal deformation, we inferred that the Lenglongling active fault dips NE rather than SW as suggested by previous studies. Considering the facts that the 2016 and 1986 M s6.4 Menyuan earthquakes are closely located with similar focal mechanisms, both of the quakes are on the north side of the Lenglongling Fault and adjacent to the fault, and the fault is dipping NE direction, we suggest that the fault should be the seismogenic structure of the two events. The Lenglongling Fault, as the western segment of the well-known Tianzhu seismic gap in the Qilian-Haiyuan active fault system, is in a relatively active state with frequent earthquakes in recent years, implying a high level of strain accumulation and a high potential of major event. It is also possible that the Lenglongling Fault and its adjacent fault, the Jinqianghe Fault in the Tianzhu seismic gap, are rupturing simultaneously in the future.

Description: Publication date: Available online 29 July 2016 Source: Geodesy and Geodynamics Author(s): Giuseppe Casula, Maria Giovanna Bianchi We present a dense crustal velocity field and corresponding strain-rate pattern computed using Global Positioning System (GPS)- Global Navigation Satellite System (GNSS) data from several hundred permanent stations in the Italian Peninsula. GPS data analysis is based on the GAMIT/GLOBK 10.6 software, which was developed and maintained mainly by Massachusetts Institute of Technology (MIT), using tools based on the distributed-sessions approach implemented in this package. The GPS data span the period from January 2008 to December 2012 and come from several different permanent GPS networks in Italy. The GLOBK package implemented in the last version of the GAMIT package is used to compute the position time-series and velocities registered in the International Terrestrial Reference Frame (ITRF) 2008. The resulting high-density intra-plate velocity field provides indications of the tectonics of the Mediterranean region. A computation of the strain-rate pattern from GPS data is performed and compared with the map of the epicentral locations of historical earthquakes that occurred in the last 1000 years in the Italian territory, showing that, in general, higher crustal deformation rates are active in regions affected by seismicity of greater magnitude.

Description: Publication date: Available online 29 July 2016 Source: Geodesy and Geodynamics Author(s): Weitao Chen, Weijun Gan, Genru Xiao, Yuebing Wang, Weiping Lian, Shiming Liang, Keliang Zhang On January 21, 2016, a strong earthquake with a magnitude of Ms 6.4 happened at Menyuan, Qinghai Province of China. In almost the same place, there was another strong earthquake happened in 1986, with similar magnitude and focal mechanism. In this paper, we analyze the characteristics of regional crustal deformation before the 2016 Menyuan Ms 6.4 earthquake by using the data from 10 continuous Global Positioning System (GPS) stations and 74 campaign-mode GPS stations within 200 km of this event: (a) Based on the velocity field from over ten years GPS observations, a regional strain rate field is calculated. The results indicate that the crustal strain rate and seismic moment accumulation rate of the Qilian-Haiyuan active fault, which is the seismogenic tectonics of the event, are significantly higher than the surrounding regions. In a 20 km × 20 km area around the seismogenic region, the maximum and minimum principal strain rates are 21.5 nanostrain/a (NW–SE extension) and −46.6 nanostrain/a (NE–SW compression), respectively, and the seismic moment accumulation rates is 17.4 N m/a. The direction of principal compression is consistent with the focal mechanism of this event. (b) Based on the position time series of the continuous GPS stations for a time-span of about 6 years before the event, we calculate the strain time series. The results show that the dilatation of the seismogenic region is continuously reduced with a “non-linear” trend since 2010, which means the seismogenic region has been in a state of compression. However, about 2–3 months before the event, both the dilatation and maximum shear strain show significant inverse trends. These abnormal changes of crustal deformation may reflect the non-linear adjustment of the stress–strain accumulation of the seismogenic region, when the accumulation is approaching the critical value of rupture.

Description: Publication date: Available online 30 July 2016 Source: Geodesy and Geodynamics Author(s): Ping He, Qi Wang, Kaihua Ding, Jie Li, Rong Zou On 3 July 2015, a Mw 6.4 earthquake occurred on a blind fault struck Pishan, Xinjiang, China. By combining Crustal Movement Observation Network of China (CMONOC) and other Static Global Positioning System (GPS) sites surrounding Pishan region, it provides a chance to constrain the slip rupture for this moderate event by GPS solutions. The maximum displacement is up to 12 cm, 2 cm for coseismic and postseismic deformation, respectively, and both the deformation patterns show a same direction moving northeastward. With rectangular dislocation model, a magnitude of Mw 6.48, Mw 6.3 is calculated based on coseismic, postseismic deformation respectively. Our result indicates the western Kunlun range is still moving toward Tarim basin followed by an obvious postseismic slip associated with this earthquake. To determine a more reasonable model for postseismic deformation, it will need a longer data set.

Description: Publication date: Available online 30 July 2016 Source: Geodesy and Geodynamics Author(s): Guiju Wu, Guangliang Yang, Hongbo Tan The research about subsurface characteristics by using transient electromagnetic method (TEM) and high density resistivity method (HDRM) were already conducted in Ordos. The objective of this research is to detect coalmine goaf areas based on rock resistivity. The data processing using wavelet transform, three point smoothing, RES2DINV and Maxwell processing software to obtain 2D resistivity structure. The results showed that the layers with maximum resistivity values (30–33 Ω m on Line 1, 30–31 Ω m on Line 2, 32–40 Ω m on Line 3) are founded at station 1–7, and 14–20 on Line 1,13–18 on Line 2, and 8–13 and 16–20 on Line 3 which is predicted as goaf layer, and the minimum resistivity values (20–26 Ω m of TEM, 45–75 Ω m of HDRM) at the other layers. This resistivity difference was caused by the geology and characteristics of the study area which is located close by the cleugh with rich coal, so the goaf area distinguishable with aquifer layer and coal seam. The results were also significant accidents and serious destruction of ecological environment.

Description: Publication date: Available online 27 July 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Fethi Kitchah, Sadok Benmebarek The stability of shallow tunnels excavated in full face has been a major challenge to the scientific community for a long time. In recent years, new techniques based on the installation of a pre-reinforcement system ahead of the tunnel face were developed to control the deformations and surface settlements induced by the excavation and to ensure the sustainability of the tunnel in the long term. In this paper, a finite difference numerical simulation was conducted to study the behaviors and effects of two pre-reinforcement systems, i.e. the face bolting and the umbrella arch system installed in a section of southern Toulon tunnel in France. For this purpose, two approaches were taken and compared: a two-dimensional (2D) approach based on the convergence-confinement method, and a three-dimensional (3D) approach taking into account the complete modeling of the tunnel. A 2D numerical back-analysis was performed to identify the geomechanical parameters that offer satisfactory agreement with the measurement results. The limit of this method lies in the exact choice of the stress relaxation ratio λ . To overcome this uncertainty, a 3D model was developed, which permitted to study the influence of different pre-support systems on the reaction of ground mass. Both 2D and 3D numerical approaches have been fitted to measurements recorded in a section of the Toulon tunnel and the very satisfactory correspondence has allowed validating the simulations. The results show that the 3D numerical analysis with a full discretization of the inclusions seems unquestionably the most reliable approach.

Description: Publication date: Available online 28 June 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Shucai Li, Rentai Liu, Qingsong Zhang, Xiao Zhang Grouting is a major method used to prevent water and mud inrush in tunnels and underground engineering. In this paper, the current situation of control and prevention of water and mud inrush is summarized and recent advances in relevant theories, grout/equipment, and critical techniques are introduced. The time-variant equations of grout viscosity at different volumetric ratios were obtained based on the constitutive relation of typical fast curing grouts. A large-scale dynamic grouting model testing system (4000 mm × 2000 mm × 5 mm) was developed, and the diffusions of cement and fast curing grouts in dynamic water grouting were investigated. The results reveal that the diffusions of cement grouts and fast curing grouts are U-shaped and asymmetric elliptical, respectively. A multi-parameter real-time monitoring system ( ϕ = 1.5 m, h = 1.2 m) was developed for the grouting process to study the diffusion and reinforcement mechanism of grouting in water-rich faulted zone. A high early strength cream-type reinforcing/plugging grout, a high permeability nano-scale silica gel grout, and a high-expansion filling grout were proposed for the control of water hazard in weak water-rich faulted zone rocks, water inrush in karst passages, and micro-crack water inrush, respectively. Complement technologies and equipment for industrial applications were also proposed. Additionally, a novel full-life periodic dynamic water grouting with the critical grouting borehole as the core was proposed. The key techniques for the control of water inrush in water-rich faulted zone, jointed fissures and karst passages, and micro-crack water inrush were developed.

Description: Publication date: Available online 4 August 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Afshin Khoshand, Mamadou Fall Natural methane (CH 4 ) oxidation that is carried out through the use of landfill covers (biocovers) is a promising method for reducing CH 4 emissions from landfills. Previous studies on peat-based landfill covers have mainly focused on their biochemical properties (e.g. CH 4 oxidation capacity). However, the utilization of peat as a cover material also requires a solid understanding of its geotechnical properties (thermal, hydraulic, and mechanical), which are critical to the performance of any biocover. Therefore, the objective of this context is to investigate and assess the geotechnical properties of peat-based cover materials (peat, peat-sand mixture), including compaction, consolidation, and hydraulic and thermal conductivities. The studied materials show high compressibility to the increase of vertical stress, with compression index ( C c ) values ranging from 0.16 to 0.358. The compressibility is a function of sand content such that the peat-sand mixture (1:3) has the lowest C c value. Both the thermal and hydraulic conductivities are functions of moisture content, dry density, and sand content. The hydraulic conductivity varies from 1.74 ×10 −9 m/s to 7.35×10 −9 m/s, and increases with the increase in sand content. The thermal conductivity of the studied samples varies between 0.54 W/(m K) and 1.41 W/(m K) and it increases with the increases in moisture and sand contents. Increases in sand content generally increase the mechanical behavior of peat-based covers; however, they also cause relatively high hydraulic and thermal conductivities which are not favored properties for biocovers.

Description: Publication date: Available online 7 July 2016 Source: Geodesy and Geodynamics Author(s): Duxin Cui, Shanlan Qin, Wenping Wang An M s6.4 earthquake occurred in the Menyuan county of Qinghai Province on Jan 21, 2016. In order to recognize the development of horizontal deformation and distinguish precursory deformation anomalies, we obtained coordinates time series, velocity and strain model around the seismic zones from processing of continuous observations from 2010 to 6 times of surveying Global Positioning System (GPS) data since 2009. The results show that, before the earthquake, the eastern segmentation of the Qilian tectonic zone where the Lenglongling Fault located is in strong crustal shortening and compressional strain state with dilatational rates of −15 to −25 ppb. The Lenglongling Fault has a strike-slip rate of 3.1 mm/a and a far-field differential orthogonal rate of 7 mm/a, while differential rate is only 1.2 mm/a near the fault, which reflects its locking feature with strain energy accumulation and high seismic risks. Dynamic evolution of deformation model shows that pre-event dilatational rates around the seismic zones increases from −15 ppb/a to −20 ppb/a with its center moving to the source areas. Time series of N components of G337 station, which is 13.7 km away from the Lenglongling Fault, exhibit a 5 mm/a acceleration anomaly. Time series of base-station QHME (in Menyuan) displays a reverse acceleration from the end of Sep. to Dec., 2016 when it comes to a largest deviation, and the accumulative displacement is more than 4 mm and the value reverse till the earthquake. In our results, coseismic displacement of N, E, U components in QHME site are 3.0 mm, 3.0 mm, −5.4 mm, respectively. If we profile these values onto the Lenglongling Fault, we can achieve a 1.1 mm of strike slip and 4.1 mm updip slip relative to the hanging wall.

Description: Publication date: Available online 7 July 2016 Source: Geodesy and Geodynamics Author(s): Weifeng Liang, Guoqing Zhang, Yiqing Zhu, Yunma Xu, Shusong Guo, Yunfeng Zhao, Fang Liu, Lingqiang Zhao In order to study the relationship between gravity variation and Menyuan M s6.4 earthquake, gravity variation characteristics in mid-eastern of Qilian Mountain were analyzed based on the 2012–2015 relative gravity datasets. The results indicated that the gravity changes in mid-eastern of Qilian Mountain increased gradually, while gravity changes around Menyuan remarkably. Besides, great positive-negative gravity changing gradients appeared along the Lenglongling Fault which was located at the north of Menyuan, and the 2016 Menyuan Ms 6.4 earthquake occurred near the junction of positive and negative gravity changes.

Description: Publication date: Available online 19 June 2016 Source: Geodesy and Geodynamics Author(s): Xin Zhao, Shuanggen Jin, Andres Calabia, Jialiang Feng The current global or regional ionospheric models have been established for monitoring the ionospheric variation. However, the spatial and temporal resolutions are not enough to describe total electron content (TEC) variations in small scale for China. In this paper, a regional ionospheric grid model (RIGM) with high spatial-temporal resolution (0.5° × 0.5° and 10-min interval) in China and surrounding areas is established based on spherical harmonics expansion from dense GPS measurements provided by Crustal Movement Observation Network of China (CMONOC) and the International GNSS Service (IGS). The correlation coefficient between the estimated TEC from GPS and the ionosonde measurements is 0.97, and the root mean square (RMS) with respect to Center for Orbit Determination in Europe (CODE) Global Ionosphere Maps (GIMs) is 4.87 TECU. In addition, the impact of different spherical harmonics orders and degrees on TEC estimations are evaluated and the degree/order 6 is better. Moreover, effective ionospheric shell heights from 300 km to 700 km are taken into account and the result indicates that 550 km is the most suitable for regional ionospheric modeling in China at solar maximum.

Description: Publication date: Available online 3 May 2016 Source: International Journal of Sustainable Built Environment Author(s): Kareem Mohamed Aldali, Wael Seddik Moustafa Taking into consideration the recent years in the economic status in Egypt, especially the investment sector will demonstrate the enormous increase in the residential buildings sector, which created massive energy consumption that never was in proportionality with the growth in the generated power in Egypt. As the residential sector consumes around 42.3% of the total energy used in Egypt, one of the main factors that waste that energy is artificial lighting and electric ventilation. Meanwhile, the architects who design those building never pay the enough attention to the energy in the design process. This paper tackles many strategies for the environmental control of building designs besides showing that now, it is essential to take into consideration energy performance efficiency and the compatibility of the building with the environment by optimizing the design of the building envelope elements such as a window to wall ratio (WWR), the glazing type. This paper will not cover the details of construction and structure, but it sheds light on many guidelines to help to raise the thermal and environmental quality of the envelope of the building. Using a computer-based simulation tool (Autodesk Ecotect) to measure a current building energy and lighting performance in one of the modern cities like Madenaty city. By the end of this study, some of the characteristics of the building envelope will be concluded like the window wall ratio in the aim to reduce the energy waste in the case study, as well as the different criteria of designing process for residential buildings in Egypt in the near future.

Description: Publication date: Available online 8 May 2016 Source: Journal of Hydrology: Regional Studies Author(s): Yeshewatesfa Hundecha, Berit Arheimer, Chantal Donnelly, Ilias Pechlivanidis Study region Europe. Study focus A semi-distributed continuous hydrological model, HYPE, was applied to model daily stream flows in more than 35,000 subcatchments across Europe. A stepwise regionalization approach was implemented to estimate different groups of model parameters. HRU based parameters were estimated first for each soil and landuse class, respectively. Lake and reservoir parameters were estimated separately. Catchments were grouped based on similarity of their characteristics and model parameters defined at a catchment scale were then regionalized for each group as functions of the catchment characteristics by simultaneously calibrating the model for a number of catchments to concurrently optimize the overall model performance and the functional relationships between the parameters and the catchment characteristics. Calibration was performed at 115 discharge stations and the approach was validated at 538 independent stations. New hydrological insights for the region Parameters could be linked to catchment descriptors with good transferability, with median NSE of 0.54 and 0.53, and median volume error of −1.6% and 1.3% in the calibration and validation stations, respectively. Although regionalizing parameters for different groups of catchments separately yielded a better performance in some groups, the overall gain in performance against regionalization using a single set of regional relationships across the entire domain was marginal. The benefits of separate regionalization were substantial in catchments with considerable proportion of agricultural landuse and higher mean annual temperature.

Description: Publication date: Available online 26 May 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): M.K. Gueddouda, I. Goual, B. Benabed, S. Taibi, N. Aboubekr This paper presents a study on the valorization of local materials such as desert dune sand obtained from Laghouat region in the South Algeria and mine bentonite intended for the realization of liner base layers in the conception of insulation barriers for hazardous waste facilities. In practice, an economical mixture satisfying the hydraulic requirements is generally concerned. First, in order to get an adequate dune sand-bentonite mixture compacted to the optimum Proctor condition, an investigation on saturated hydraulic behavior is carried out in this study for different mixtures. Using oedometer test (indirect measurement), the adequate mixture of 85% dune sand and 15% bentonite satisfies the conditions of saturated hydraulic conductivity ( k 〈 10 -9 m/s). This result of the adequate mixture is also confirmed by direct measurement of saturated hydraulic conductivity using triaxial cell. Second, the unsaturated hydraulic conductivity of the adequate mixture is measured with an original vapor equilibrium technique (VET) used for S r 〈 30% (very high suction s > 3 MPa). This technique is conducted based on the exploitation of the water retention curve in order to establish the relationships between hydraulic conductivity, degree of saturation, and suction. It shows that the hydraulic conductivity increases with the degree of saturation and decreases with the suction. However, the hydraulic conductivity has a constant value for suctions larger than 20 MPa. The selected dune sand-bentonite mixture satisfies the regulation requirements and hence constitutes a good local and economical material for the conception of barrier base liners.

Description: Publication date: Available online 26 May 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Murtala Umar, Khairul Anuar Kassim, Kenny Tiong, Ping Chiet The concept of using biological process in soil improvement which is known as bio-mediated soil improvement technique has shown greater potential in geotechnical engineering applications in terms of performance and environmental sustainability. This paper presents a review on the soil microorganisms responsible for this process, and factors that affect their metabolic activities and geometric compatibility with the soil particle sizes. Two mechanisms of biomineralization, i.e. biologically controlled and biologically induced mineralization, were also discussed. Environmental and other factors that may be encountered in situ during microbially induced calcite precipitation (MICP) and their influences on the process were identified and presented. Improvements in the engineering properties of soil such as strength/stiffness and permeability as evaluated in some studies were explored. Potential applications of the process in geotechnical engineering and the challenges of field application of the process were identified.

Description: Publication date: Available online 26 May 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): An-Bin Huang, Chien-Chih Wang, Jui-Ting Lee, Yen-Te Ho Over the past few decades, many optical fiber sensing techniques have been developed. Among these available sensing methods, optical fiber Bragg grating (FBG) is probably the most popular one. With its unique capabilities, FBG-based geotechnical sensors can be used as a sensor array for distributive (profile) measurements, deployed under water (submersible), for localized high resolution and/or differential measurements. The authors have developed a series of FBG-based transducers that include inclination, linear displacement and gauge/differential pore pressure sensors. Techniques that involve the field deployment of FBG inclination, extension and pore-pressure sensor arrays for automated slope stability and ground subsidence monitoring have been developed. The paper provides a background of FBG and the design concepts behind the FBG-based field monitoring sensors. Cases of field monitoring using the FBG sensor arrays are presented, and their practical implications are discussed.

Description: Publication date: Available online 21 July 2016 Source: Geodesy and Geodynamics Author(s): Jianlin Feng, Jin Wei, Yujuan Tan, Jianzeng Qin, Bangwu Huang, Ruyi Xie In this study, a classic survey adjustment computation method was used for data obtained in the Inner Mongolia and Ningxia gravimetric networks between September 2013 and April 2015 so as to investigate the variation of gravity before the Alxa Zuoqi M 5.8 earthquake. The relationship between gravity variation and the Alxa Zuoqi M 5.8 earthquake was analyzed. The results showed that: (1) the severe variation in gravity field at the test sites before the Alxa Zuoqi M 5.8 earthquake, as well as the subsequent accelerated rising, might be an earthquake precursor; (2) the Alxa Zuoqi M 5.8 earthquake occurred at the turning point where the high-gravity gradient zone changed from the NE direction to NW.

Description: Publication date: Available online 30 June 2016 Source: International Journal of Sustainable Built Environment Author(s): Iman Khajehzadeh, Brenda Vale, Fatemeh Yavari For many years central court houses have been used in parts of Iran with different climates. Though initially there appear to be many similarities, some aspects of these houses vary from one climatic zone to another. Several studies have also suggested that users of these houses moved within them as they sought for better thermal situations. This article sets out how differing sizes, forms and dimensional ratios of central courts in two climate zones of Iran (Yazd, hot and dry, and Bushehr, hot and humid) can support this behaviour. In both places these central court forms can provide good situations for human comfort on various sides and levels of the court. Consequently, residents could move within the house with the seasons to get their desired level of thermal comfort but these traditional patterns of movement differ for each climate zone.

Description: Publication date: Available online 30 June 2016 Source: International Journal of Sustainable Built Environment Author(s): Aziz. I. Abdulla, Hashim Abdul Razak, Yassen Ali Salih, Muataz Ibrahim Ali This study is an experimental investigation into the properties of adhesive before and after mixing with fine sand, and its behavior on reinforced concrete beams strengthened by CFRP to show the effects of modified adhesive on load-carrying capacity, ductility, stiffness and failure mode of the reinforced concrete beams. Compressive strength, flexural strength and the effect of high temperature on these properties were the focus of the current study in order to prove the efficiency of adding fine sand to improve adhesive properties and reduce cost. Based on the compressive and flexural tests, results indicated that the addition of sand to the adhesive improved its mechanical properties when sand is 50% of the total weight of the adhesive. However, its effect on the modulus of elasticity is minimal. Using adhesive with fine sand increased the ultimate load bearing capacity, ductility, stiffness and toughness of the reinforced concrete beams strengthened by CFRP. The ratio of the fine sand to the adhesive equal to 1 is considered the best in terms of the cost reduction, maintaining workability, as well as maintaining the mechanical properties. Lastly, the use of fine sand with adhesive ensured a significant reduction in the cost of the adhesive and increased the adhesive resistance to temperature.

Description: Publication date: Available online 30 June 2016 Source: International Journal of Sustainable Built Environment Author(s): Adil Umer, Kasun Hewage, Husnain Haider, Rehan Sadiq Growing environmental and socioeconomic concerns due to rapid urbanization, population growth and climate change impacts have motivated decision-makers to incorporate sustainable best practices for transportation infrastructure development and management. A “sustainable” transportation infrastructure implies that all the sustainability objectives (i.e., mobility, safety, resource efficiency, economy, ecological protection, environmental quality) are adequately met during the infrastructure life cycle. State-of-the-art sustainability rating tools contain the best practices for the sustainability assessment of infrastructure projects. Generally, the existing rating tools are not well equipped to handle uncertainties associated with data limitations and expert opinion and cannot effectively adapt to site specific constraints for reliable sustainability assessment. This paper presents the development of a customizable tool, called “Green Proforma” for the sustainability assessment of roadway projects under uncertainties. For evaluating how well the project meets sustainability objectives, a hierarchical framework is used to develop the sustainability objective indices by aggregating the selected indicators with the help of fuzzy synthetic evaluation technique. These indices are further aggregated to attain an overall sustainability index for a roadway project. To facilitate the decision makers, a “Roadway Project Sustainometer” has been developed to illustrate how well the roadway project is meeting its sustainability objectives. By linking the sustainability objectives to measurable indicators, the “Green Proforma” paves the way for a practical approach in sustainable planning and management of roadway projects.

Description: Publication date: Available online 12 July 2016 Source: International Journal of Sustainable Built Environment Author(s): Jnyanendra Kumar Prusty, Sanjaya Kumar Patro, S.S. Basarkar High demand of natural resources due to rapid urbanization and the disposal problem of agricultural wastes in developed countries have created opportunities for use of agro-waste in the construction industry. Many agricultural waste materials are already used in concrete as replacement alternatives for cement, fine aggregate, coarse aggregate and reinforcing materials. This paper reviews some of the agro-waste materials, which are used as a partial replacement of fine aggregate in concrete. Different properties of fresh and hardened concrete, their durability and thermal conductivity when admixed with agro-wastes are reviewed. Agro-waste used in self-compacting concrete and mortar are also reviewed and their properties are compared. It has been seen that the agro-waste concrete containing groundnut shell, oyster shell, cork, rice husk ash and tobacco waste showed better workability than their counterparts did. Agro-waste concrete containing bagasse ash, sawdust ash and oyster shell achieved their required strength by 20% of replacement as fine aggregate, which were maximum among all agro-waste type concrete. Close relations were predicted among compressive strength, flexural strength, tensile strength, ultrasonic pulse velocity and elastic modulus of agro-waste concrete. Addition of bagasse ash as fine aggregate in mortar increased the resistance of chloride penetration whereas inclusion of cork in mortar showed better thermal resistance and improved cyclic performance. After the review, it is of considerable finding that more research is deserved on all fine aggregates replacing agro-waste materials, which can give more certainty on their utilization in concrete.

Description: Publication date: Available online 5 July 2016 Source: International Journal of Sustainable Built Environment Author(s): R. Nagaraj, D. Thirugnanamurthy, Manik Murthy Rajput, B.K. Panigrahi Water and energy are two inseparable commodities that govern the lives of humanity and promote civilization. Energy can be used to produce water in case of scarcity in water. Ironically most of the places that are water stressed are also energy stressed. The cost of extending grid power may be prohibitively high in those cases. Rural/remote locations like hills and islands multiply the problem to a larger magnitude. Use of renewable sources like solar, wind, biomass and other locally available energy sources is the only solution. But these renewable sources are of intermittent nature and have poor availability. Hence, it is practically difficult to produce water with a single source of energy. Naturally, combining two or more sources of energy, known as hybrid power system, is the next available option. This paper carries out a techno-economic analysis of various sizing combinations of systems with solar photo voltaic, wind energy and stored energy in batteries for production of drinking water from a brackish water source. The system can operate the RO plant whenever the power is available, produce drinking water and store in a tank. This paper analyses the model of the entire hybrid power system in MATLAB to simulate the performance of the hybrid power system for different combinations of capacities. Results of the analysis under various input conditions are analyzed.

Description: Publication date: Available online 26 July 2016 Source: Geodesy and Geodynamics Author(s): Yaxuan Hu, Ming Hao, Lingyun Ji, Shangwu Song Hainan Island is a seismic active region, where Qiongshan M 7.5 earthquake occurred in 1605 and several seismic belts appeared in recent years, especially the NS trending seismic belt (NSB) located in the northeast part of the island. Here is also a magmatic active region. The lava from about 100 volcanoes covered more than 4000 km 2 . The latest eruptions occurred on Ma'anling–Lei Huling volcanoes within 10,000 years. The neotectonic movement has been determined by geological method in the island and its adjacent areas. In the paper, the present-day 3D crustal movement is obtained by using Global Positioning System (GPS) data observed from 2009 to 2014 and leveling observations measured in 1970s and 1990s respectively. The results show the horizontal movement is mainly along SEE direction relative to the Eurasian Plate. The velocities are between 4.01 and 6.70 mm/a. The tension rate near the NSB is less than 1 mm/a. The vertical movement shows the island uplifts as a whole with respect to the reference benchmark Xiuyinggang. The average uplifting rate is 2.4 mm/a. The rates are 2–3 mm/a in the northwest and 3–5mm/a in the northwest. It shows the deformation pattern of the southwest island is upward relative to the northeast, which is different from the result inferred from the coastal change and GPS. Haikou and its adjacent region present a subsidence in a long time. The southern part of the middle segment of the Wangwu-Wenjiao fault uplifts relative to the northern. Meanwhile, the western part uplifts relative to the eastern NSB. The vertical crustal motion and the two normal faults nearly correspond to the terrain. The NSB is located along the Puqiangang-Dazhibo fault, which is assessed as a segmented fault with a dip of 80°–90°and partly exposed. The 3D deformations and other studies reveal the present activities of earthquakes, volcanoes and the faults. The small earthquakes will still occur in the NS belt and the volcanoes are not active now.

Description: Publication date: Available online 24 March 2016 Source: International Journal of Sustainable Built Environment Author(s): Yunzhi Tan, Mozhen Hu, Dianqing Li Lateritic soil with high liquid-limits is commonly used for roadbed construction. However lateritic soil has properties that are sensitive to moisture, and therefore a common method of treating the soil is by adding lime to it. However, it is difficult to mix lime with lateritic soil homogeneously in the field as lateritic soil is prone to agglomeration. Therefore, agglomeration size is important and in this study, soil agglomerates are tested for their California bearing ratio (CBR). Lime (Ca(OH) 2 ) is added to one of the groups of soil samples and the other group is left untreated. The results show that soil that has been treated with lime both hardens and softens, which is related to the agglomerate size, whereas the untreated soil just hardens. The agglomerate size that corresponds to the maximum CBR value is not consistent with that of maximum dry density. Moreover, the CBR values of soil that has been treated with lime are higher than those of the untreated soil for an agglomerate size that ranges from 0.5 mm to 2 cm. Beyond this range, the addition of lime does not improve the lateritic soil. Compaction status and water intrusion are two important influential factors on CBR values. Therefore, it is necessary to take further measures to prevent moisture infiltration and migration of water.

Description: Publication date: Available online 25 March 2016 Source: Geodesy and Geodynamics Author(s): Xinlin Zhang, Shuhei Okubo, Yoshiyuki Tanaka, Hui Li The greatest earthquake in the modern history of Japan and probably the fourth greatest in the last 100 years in the world occurred on March 11, 2011 off the Pacific coast of Tohoku. Large tsunami and ground motions caused severe damage in wide areas, particularly many towns along the Pacific coast. So far, gravity change caused by such a great earthquake has been reported for the 1964 Alaska and the 2010 Maule events. However, the spatial-temporal resolution of the gravity data for these cases is insufficient to depict a co-seismic gravity field variation in a spatial scale of a plate subduction zone. Here, we report an unequivocal co-seismic gravity change over the Japanese island, obtained from a hybrid gravity observation (combined absolute and relative gravity measurements). The time interval of the observation before and after the earthquake is within 1 year at almost all the observed sites, including 13 absolute and 16 relative measurement sites, which deduced tectonic and environmental contributions to the gravity change. The observed gravity agrees well with the result calculated by a dislocation theory based on a self-gravitating and layered spherical earth model. In this computation, a co-seismic slip distribution is determined by an inversion of Global Positioning System (GPS) data. Of particular interest is that the observed gravity change in some area is negative where a remarkable subsidence is observed by GPS, which can not be explained by simple vertical movement of the crust. This indicated that the mass redistribution in the underground affects the gravity change. This result supports the result that Gravity Recovery and Climate Experiment (GRACE) satellites detected a crustal dilatation due to the 2004 Sumatra earthquake by the terrestrial observation with a higher spatial and temporal resolution.

Description: Publication date: Available online 25 March 2016 Source: Geodesy and Geodynamics Author(s): Lifen Zhang, Jinggang Li, Wulin Liao, Qiuliang Wang On 25 April, 2015, an M w7.9 earthquake occurred in Nepal, which caused great economic loss and casualties. However, almost no surface ruptures were observed. Therefore, in order to interpret the phenomenon, we study the rupture process of the earthquake to seek answers. Inversion of teleseismic body-wave data is applied to estimate the rupture process of the 2015 Nepal earthquake. To obtain stable solutions, smoothing and non-negative constraints are introduced. 48 teleseismic stations with good coverage are chosen. Finite fault model is established with length and width of 195 km and 150 km, and we set the initial seismic source parameters referring to CMT solutions. Inversion results indicate that the focal mechanism of this earthquake is a thrust fault type, and the strike, dip and rake angle are in accordance with CMT results. The seismic moment is 0.9195 × 10 21  Nm ( M w7.9), and source duration is about 70 s. The rupture nucleated near the hypocenter and then propagated along the dip direction to the southeast, and the maximum slip amounts to 5.2 m. Uncertainties on the amount of slip retrieved by different inversion methods still exist, the overall characteristics are inconsistent. The lack of shallow slip during the 2015 Gorkha earthquake implies future seismic hazard and this region should be paid more attention to.

Description: Publication date: June 2016 Source: Journal of Hydrology: Regional Studies, Volume 6 Author(s): Haiyun Shi, Tiejian Li, Jiahua Wei, Wang Fu, Guangqian Wang Study region Three-River Headwaters (TRH) region, China. Study focus Precipitation is regarded as the basic component of the global hydrological cycle. This study investigated the spatial and temporal characteristics of precipitation over the TRH region during 1961–2014, based on the observed data of 29 meteorological stations. New hydrological insights for the region The results showed that: (1) temporally, the TRH region has experienced a significant increasing trend in the annual precipitation ( p 〈 0.1) during 1961–2014, especially in the dry season ( p 〈 0.01). (2) Spatially, the mean annual precipitation (MAP) in the TRH region showed the southeast-to-northwest decreasing trend and the annual precipitation recorded at most stations (i.e., 26 in 29) presented the increasing trends. (3) A close correlation of the MAP with elevation was found, that is, a low-to-high increasing trend below 3800 m but an inverse correlation above 3800 m; in addition, statistical equations to estimate precipitation with high R 2 values were established based on longitude, latitude and elevation. (4) Characteristics of related meteorological variables and possible impact of precipitation on runoff were analyzed and discussed. These results would be valuable for the researchers to better understand the changing characteristics of precipitation and for the managers to make better decisions in the future.

Description: Publication date: Available online 4 April 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Long Zhang, Qiang Yang, Yaoru Liu The time-dependent behavior of the left bank abutment slope at Jinping I hydropower station has a major influence on the normal operation and long-term safety of the hydropower station. To solve this problem, a geomechanical model containing various faults and weak structural planes is established, and numerical simulation is conducted under normal water load condition using FLAC 3D , incorporating creep model proposed based on thermodynamics with internal state variables theory. The creep deformations of the left bank abutment slope are obtained, and the changes of principal stresses and deformations of the dam body are analyzed. The long-term stability of the left bank abutment slope is evaluated according to the integral curves of energy dissipation rate in domain and its derivative with respect to time, and the non-equilibrium evolution rules and the characteristic time can also be determined using these curves. Numerical results show that the left bank abutment slope tends to be stable in a global sense, and the stress concentration is released. It is also indicated that more attention should be paid to some weak regions within the slope in long-term deformation process.

Description: Publication date: Available online 9 April 2016 Source: International Journal of Sustainable Built Environment Author(s): Suinyuy Derrick Ngoran, Xiong Zhi Xue, Presley K. Wesseh We adapt the transcendental logarithmic (translog) production model to examine the role of water resources consumption on economic growth in 38 Sub-Saharan African (SSA) countries. Labor, capital and energy are incorporated into the model to provide for omitted variable biased. Several findings have been documented from the investigation. First, the results suggest that economic growth in SSA is driven mainly by water and labor. Capital and energy were found not to significantly drive economic growth. Second, technical change in SSA is scale-biased and factor augmenting; suggesting that efficiency of water withdrawals and labor use would lead to technological progress in SSA. Third, substitution possibilities between water and labor exist indicating that restrictions on water withdrawals would lead to labor intensiveness and vice versa. Finally, a more general insight from the study is that efficient use of water resources promotes technological innovation and hence, critical for sustainable development.

Description: Publication date: Available online 9 April 2016 Source: International Journal of Sustainable Built Environment Author(s): Rosaria Ciriminna, Mario Pagliaro, Francesco Meneguzzo, Mario Pecoraino Following first attempts in the early 1980s that provided useful information on the reliability of the photovoltaic energy generation, Sicily’s remote islands share a number of pioneering achievements in the utilization of solar energy. This study aims to assess progress and the remaining gaps in the large-scale adoption of renewable energy in said numerous islands. We identify the most advantageous technologies and suggest pragmatic actions, so as to allow new stakeholder commitment for further progress in the forthcoming transition from fossil to renewable energy.

Description: Publication date: March 2016 Source: Journal of Hydrology: Regional Studies, Volume 5 Author(s): Eric Nicolini, Karyne Rogers, Delphine Rakowski Study region Lifou Island, near the main island of New Caledonia. Study focus Stable oxygen and hydrogen isotopes of groundwater and rainfall were used to characterise baseline values for the main fresh water aquifer of Lifou Island and describe its recharge. Other stable isotope parameters (nitrates and DIC) were used to investigate the interaction between surface water (rainfall) and groundwater, including anthropogenic effects from human activities. New hydrological insights for the region This study represents the first baseline isotopic characterisation of Lifou Island’s groundwater aquifer composition and provides a reference for future investigative studies on groundwater quality and security. Groundwater sampled in June and October 2012 had nearly identical isotopic composition. Tap water sampled monthly between February 2012 and January 2014 also had a constant isotopic composition similar to the groundwater. Groundwater recharge was found to occur when monthly precipitation exceeded 140 mm, with the recharge cycle representing 20–30% of the annual rainfall. Relationships between HCO 3 2− content, pH, soil δ 13 C DIC and satellite photo interpretation suggests a variance of soil pCO 2 , which is explained by different vegetation cover and higher water use efficiencies in forested areas (high pCO 2 , more negative δ 13 C isotope values). The δ 15 N NO3 values for most groundwater indicate they are uncontaminated with anthropogenic nitrates, although some samples taken in October (dry season) showed a slight denitrification, possibly of natural origin.

Description: Publication date: December 2016 Source: Journal of Hydrology: Regional Studies, Volume 5, Supplement 1 Author(s): Anonymous

Description: Publication date: Available online 7 January 2016 Source: Geodesy and Geodynamics Author(s): Chen Zhiyao, Lǖ Pinji, Tang Lei This work analyzes the quality of crustal tilt and strain observations during 2014, which were acquired from 269 sets of ground tiltmeters and 212 sets of strainmeters. In terms of data quality, the water tube tiltmeters presented the highest rate of excellent quality, approximately 91%, and the pendulum tiltmeters and ground strainmeters yielded rates of 81% and 78%, respectively. This means that a total of 380 sets of instruments produced high-quality observational data suitable for scientific investigations and analyses.

Description: Publication date: December 2016 Source: Journal of Hydrology: Regional Studies, Volume 5, Supplement 1 Author(s): Anonymous

Description: Publication date: Available online 4 January 2016 Source: Geodesy and Geodynamics Author(s): Anju Pandey, Dhananjai K. Pandey Continental rifting and magmatism has been extensively studied worldwide as it is believed that continental rifting, break up of continents and associated magmatism lead to genesis of new oceanic crust. However, various regions of the world show that these processes may lead to genesis of other types of crust than the oceanic crust. Laxmi Basin in the western continental margin of the India is one such region with an enigmatic crust. Due to its extreme strategic significance for the palaeogeographic reconstruction of continents during Cretaceous continental breakup of India, this basin has attracted various workers for more than two decades. However, still the issue of nature of crust in the basin remains controversial. In this contribution, in order to identify nature of crust, mechanism of continental extension in the Laxmi Basin has been studied for the first time through newly acquired seismic data from the basin. Here, we propose a plausible mechanism of crustal extension in the Laxmi Basin which eventually constrains the nature of crust of the Laxmi Basin. We have demonstrated that the crust in the Laxmi Basin can be categorised in two zones of stretched and transitional crust. In the stretched zone several fault bounded horst and graben structures are identified which preserve syn- and post-rift sediments along with different periods of hiatus in sedimentations as unconformities. These faults are identified as listric faults in the upper crust which sole out in the detachment faults. Detachment faults decouples the upper brittle and lower ductile crust. The transitional crust is identified as heavily intruded by sills and basaltic volcanic were emplaced due to melting of subcontinental mantle (SCM) after hyper-stretching of crust and serpentinisation of the SCM. Panikkar Ridge is proposed to be one such basaltic volcanic body derived from melting of lower part of SCM.

Description: Publication date: Available online 5 January 2016 Source: Journal of Hydrology: Regional Studies Author(s): Daniel J. Hoover, Kingsley O. Odigie, Peter W. Swarzenski, Patrick Barnard Study region The study region spans coastal California, USA, and focuses on three primary sites: Arcata, Stinson Beach, and Malibu Lagoon. Study focus 1 m and 2 m sea-level rise (SLR) projections were used to assess vulnerability to SLR-driven groundwater emergence and shoaling at select low-lying, coastal sites in California. Separate and combined inundation scenarios for SLR and groundwater emergence were developed using digital elevation models of study site topography and groundwater surfaces constructed from well data or published groundwater level contours. New hydrological insights for the region SLR impacts are a serious concern in coastal California which has a long (∼1800 km) and populous coastline. Information on the possible importance of SLR-driven groundwater inundation in California is limited. In this study, the potential for SLR-driven groundwater inundation at three sites (Arcata, Stinson Beach, and Malibu Lagoon) was investigated under 1 m and 2 m SLR scenarios. These sites provide insight into the vulnerability of Northern California coastal plains, coastal developments built on beach sand or sand spits, and developed areas around coastal lagoons associated with seasonal streams and berms. Northern California coastal plains with abundant shallow groundwater likely will see significant and widespread groundwater emergence, while impacts along the much drier central and southern California coast may be less severe due to the absence of shallow groundwater in many areas. Vulnerability analysis is hampered by the lack of data on shallow coastal aquifers, which commonly are not studied because they are not suitable for domestic or agricultural use. Shallow saline aquifers may be present in many areas along coastal California, which would dramatically increase vulnerability to SLR-driven groundwater emergence and shoaling. Improved understanding of the extent and response of California coastal aquifers to SLR will help in preparing for mitigation and adaptation.

Description: Publication date: June 2016 Source: Journal of Hydrology: Regional Studies, Volume 6 Author(s): Bogdan Ozga-Zielinski, Maurycy Ciupak, Jan Adamowski, Bahaa Khalil, Julien Malard Study region Narew River in Northeastern Poland. Study focus Three methods for frequency analysis of snowmelt floods were compared. Two dimensional (2D) normal distribution and copula-based 2D probability distributions were applied to statistically describe floods with two parameters (flood peak Q max,f and flood volume V f ). Two copula functions from different classes – the elliptical Gaussian copula and Archimedean 1-parameter Gumbel–Hougaard copula – were evaluated based on measurements. New hydrological insights for the region The results indicated that the 2D normal probability distribution model gives a better probabilistic description of snowmelt floods characterized by the 2-dimensional random variable ( Q max,f , V f ) compared to the elliptical Gaussian copula and Archimedean 1-parameter Gumbel–Hougaard copula models, in particular from the view point of probability of exceedance as well as complexity and time of computation. Nevertheless, the copula approach offers a new perspective in estimating the 2D probability distribution for multidimensional random variables. Results showed that the 2D model for snowmelt floods built using the Gumbel–Hougaard copula is much better than the model built using the Gaussian copula.

Description: Publication date: Available online 24 March 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Chandrakant S. Desai, Xiao Yang

Description: Publication date: Available online 31 March 2016 Source: International Journal of Sustainable Built Environment Author(s): Shailza Singh A Class II level field survey is conducted in five naturally ventilated multi-storied apartments in the composite climatic zone of north India. A total of 984 data-sets were collected for the whole year, involving over 82 subjects and 55 apartment units. This paper highlighted the season-wise behavioural change in the usage pattern of controls and the resultant thermal response of the subjects. It is observed that at extreme weather conditions, subjects are switching to ‘seasonal controls’(i.e. fans, A/C’s and heaters/hot blowers) as oppose to the ‘designed controls’ (i.e. windows, balcony doors and blinds) or personal controls (i.e. changing ‘clo’ and ‘met’ levels).The study concludes that if designed controls are efficiently incorporated in the building the thermal perception of the residents and the resultant energy consumption can be improved.

Description: Publication date: Available online 1 April 2016 Source: International Journal of Sustainable Built Environment Author(s): Yousef Al horr, Mohammed Arif, Martha Katafygiotou, Ahmed Mazroei, Amit Kaushik, Esam Elsarrag Indoor Environmental Quality (IEQ) and its effect on occupant well-being and comfort is an important area of study. This paper presents a state of the art study through extensive review of the literature, by establishing links between IEQs and occupant well-being and comfort. A range of issues such as sick building syndrome, indoor air quality thermal comfort, visual comfort and acoustic comfort are considered in this paper. The complexity of the relationship between occupant comfort and well-being parameters with IEQ are further exacerbated due to relationships that these parameters have with each other as well. Based on the review of literature in these areas it is established that design of buildings needs to consider occupant well-being parameters right at the beginning. Some good practices in all these different areas have also been highlighted and documented in this paper. The knowledge established as part of this paper would be helpful for researchers, designer, engineers and facilities maintenance engineers. This paper will also be of great benefit to researchers who endeavour to undertake research in this area and could act as a good starting point for them.

Description: Publication date: Available online 1 April 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Chandrakant S. Desai A unified constitutive modeling approach is highly desirable to characterize a wide range of engineering materials subjected simultaneously to the effect of a number of factors such as elastic, plastic and creep deformations, stress path, volume change, microcracking leading to fracture, failure and softening, stiffening, and mechanical and environmental forces. There are hardly available such unified models. The disturbed state concept (DSC) is considered to be a unified approach and is able to provide material characterization for almost all of the above factors. This paper presents a description of the DSC, and statements for determination of parameters based on triaxial, multiaxial and interface tests. Statements of DSC and validation at the specimen level and at the boundary value problem levels are also presented. An extensive list of publications by the author and others is provided at the end. The DSC is considered to be a unique and versatile procedure for modeling behaviors of engineering materials and interfaces.

Description: Publication date: Available online 1 April 2016 Source: Journal of Hydrology: Regional Studies Author(s): Demetris Koutsoyiannis, Günter Blöschl, András Bárdossy, Christophe Cudennec, Denis Hughes, Alberto Montanari, Insa Neuweiler, Hubert Savenije

Description: Publication date: Available online 4 April 2016 Source: Geodesy and Geodynamics Author(s): Ayman Hassan, Shuanggen Jin Continental water storage plays a major role in Earth's climate system. However, temporal and spatial variations of continental water are poorly known, particularly in Africa. Gravity Recovery and Climate Experiment (GRACE) satellite mission provides an opportunity to estimate terrestrial water storage (TWS) variations at both continental and river-basin scales. In this paper, seasonal and secular variations of TWS within Africa for the period from January 2003 to July 2013 are assessed using monthly GRACE coefficients from three processing centers (Centre for Space Research, the German Research Centre for Geosciences, and NASA's Jet Propulsion Laboratory). Monthly grids from Global Land Data Assimilation System (GLDAS)-1 and from the Tropical Rainfall Measuring Mission (TRMM)-3B43 models are also used in order to understand the reasons of increasing or decreasing water storage. Results from GRACE processing centers show similar TWS estimates at seasonal timescales with some differences concerning inter-annual trend variations. The largest annual signals of GRACE TWS are observed in Zambezi and Okavango River basins and in Volta River Basin. An increasing trend of 11.60 mm/a is found in Zambezi River Basin and of 9 mm/a in Volta River Basin. A phase shift is found between rainfall and GRACE TWS (GRACE TWS is preceded by rainfall) by 2–3 months in parts of south central Africa. Comparing GLDAS rainfall with TRMM model, it is found that GLDAS has a dry bias from TRMM model.

Description: Publication date: Available online 4 April 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Suman Panthee, P.K. Singh, Ashutosh Kainthola, T.N. Singh Tunneling in complex rock mass conditions is a challenging task, especially in the Himalayan terrain, where a number of unpredicted conditions are reported. Rock joint parameters such as persistence, spacing and shear strength are the factors which significantly modify the working environments in the vicinity of the openings. Therefore, a detailed tunnel stability assessment is critically important based on the field data collection on the excavated tunnel’s face. In this context, intact as well as rock mass strength and deformation modulus is obtained from laboratory tests for each rock type encountered in the study area. Finite element method (FEM) is used for stability analysis purpose by parametrically varying rock joint persistence, spacing and shear strength parameters, until the condition of overbreak is reached. Another case of marginally stable condition is also obtained based on the same parameters. The results show that stability of tunnels is highly influenced by these parameters and the size of overbreak is controlled by joint persistence and spacing. Garnetiferous schist and slate characterized using high persistence show the development of large plastic zones but small block size, depending upon joint spacing; whereas low persistence, low spacing and low shear strength in marble and quartzite create rock block fall condition.

Description: Publication date: Available online 5 April 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Rennie B. Kaunda, Brian Asbury The material and elastic properties of rocks are utilized for predicting and evaluating hard rock brittleness using artificial neural networks (ANN). Herein hard rock brittleness is defined using Yagiz' method. A predictive model is developed using a comprehensive database compiled from 30 years' worth of rock tests at the Earth Mechanics Institute (EMI), Colorado School of Mines. The model is sensitive to density, elastic properties, and P- and S-wave velocities. The results show that the model is a better predictor of rock brittleness than conventional destructive strength-test based models and multiple regression techniques. While the findings have direct implications on intact rock, the methodology can be extrapolated to rock mass problems in both tunneling and underground mining where rock brittleness is an important control.

Description: Publication date: Available online 4 April 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): C. Auvray, N. Lafrance, D. Bartier Toarcian claystone such as that of the Callovo-Oxfordian is a qualified multiphase material. The claystone samples tested in this study are composed of four main mineral phases: silicates (clay minerals, quartz, feldspars, micas) (≈86%), sulphides (pyrite) (≈3%), carbonates (calcite, dolomite) (≈10%) and organic kerogen (≈1%). Three sets of measurements of the modulus of deformability were compared as determined in (i) nano-indentation tests with a constant indentation depth of 2 μm, (ii) micro-indentation tests with a constant indentation depth of 20 μm, and (iii) meso-compression tests with a constant displacement of 200 μm. These three experimental methods have already been validated in earlier studies. The main objective of this study is to demonstrate the influence of the scaling effect on the modulus of deformability of the material. Different frequency distributions of the modulus of deformability were obtained at the different sample scales: (i) in nano-indentation tests, the distribution was spread between 15 GPa and 90 GPa and contained one peak at 34 GPa and another at 51 GPa; (ii) in the micro-indentation tests, the distribution was spread between 25 GPa and 60 GPa and displayed peaks at 26 GPa and 37 GPa; and (iii) in the meso-compression tests, a narrow frequency distribution was obtained, ranging from 25 GPa to 50 GPa and with a maximum at around 35 GPa.

Description: Publication date: Available online 6 April 2016 Source: International Journal of Sustainable Built Environment Author(s): Vandna Sharma, Bhanu M Marwaha, Hemant K Vinayak Low Durability and compressive strength of adobe blocks leads to frequent maintenance problem associated with rural house wall construction. This forms the main reason of abandonment of vernacular mud housing building technology in rural areas today. Present paper presents an attempt to improve upon the low durability of adobe blocks by addition of natural reinforcement of Grewia Optiva and Pinus Roxburghii which otherwise are treated as waste material in rural areas. Experimental investigations were carried out for cylindrical and cubical stabilized and unstabilized soil samples. Durability tests conducted included Wetting and Drying Test, Water absorption and expansion test, Sponge Water absorption test, Spray Test, Total absorption test, Water Strength Coefficient tests carried out as per Indian standards and international research. Results indicated that durability of stabilized soil samples increases by 72% and 68% for fibers of Grewia Optiva and Pinus Roxburghii as compared with unstabilized soil samples. The results recommend that fibers of Grewia Optiva and Pinus Roxburghii can be advantageously added in adobe blocks for improving durability. This would propagate durable mud housing on large scale thereby reducing housing shortage especially in developing countries, economizing use of natural resources, reducing energy consumption during manufacturing of modern construction materials and most importantly provide sustainable way of living.

Description: Publication date: Available online 17 August 2016 Source: Geodesy and Geodynamics Author(s): Dongzhuo Xu, Chuanbao Zhu, Xiangang Meng, Yuan Li, Qikai Sun, Ke Zhang Fault deformation characteristics in the northern margin of the Tibetan Plateau before the Menyuan M s6.4 earthquake are investigated through time-series and structural geological analysis based on cross-fault observation data from the Qilian Mountain–Haiyuan Fault belt and the West Qinling Fault belt. The results indicate: 1) Group short-term abnormal variations appeared in the Qilian Mountain–Haiyuan Fault belt and the West Qinling Fault belt before the Menyuan M s6.4 earthquake. 2) More medium and short-term anomalies appear in the middle-eastern segment of the Qilian Mountain Fault belt and the West Qinling Fault belt, suggesting that the faults' activities are strong in these areas. The faults' activities in the middle-eastern segment of the Qilian Fault belt result from extensional stress, as before the earthquake, whereas those in the West Qinling Fault belt are mainly compressional. 3) In recent years, moderate-strong earthquakes occurred in both the Kunlun Mountain and the Qilian Mountain Fault belts, and some energy was released. It is possible that the seismicity moved eastward under this regime. Therefore, we should pay attention to the West Qinling Mountain area where an M s6–7 earthquake could occur in future.

Description: Publication date: Available online 24 August 2016 Source: Geodesy and Geodynamics Author(s): Zhiping Liu, Sida Li, Hefang Bian Based on the deficiency of the traditional total least squares method (TLS) in the field of geodetic inversion, the mixed error characteristics of the errors in variables (EIV) model were analyzed by considering the distance azimuth measurement error in strain inversion from distance changes, which resulted in the improved mixed total least squares method (IMTLS) with generalized mixed EIV model. Finally, three comparison schemes of strain inversion from distance changes using measured data were implemented to test the proposed method. The results showed that the IMTLS method outperformed the traditional least squares (LS) and TLS methods in parameters estimation, accuracy evaluation, actual EIV model characteristics, and five strain eigenvalues.

Description: Publication date: Available online 23 August 2016 Source: Geodesy and Geodynamics Author(s): Yannan Zhao, Yuan Li, Lifen Zhang, Qiuliang Wang According to groundwater level monitoring data of Shuping landslide in the Three Gorges Reservoir area, based on the response relationship between influential factors such as rainfall and reservoir level and the change of groundwater level, the influential factors of groundwater level were selected. Then the classification and regression tree (CART) model was constructed by the subset and used to predict the groundwater level. Through the verification, the predictive results of the test sample were consistent with the actually measured values, and the mean absolute error and relative error is 0.28 m and 1.15% respectively. To compare the support vector machine (SVM) model constructed using the same set of factors, the mean absolute error and relative error of predicted results is 1.53 m and 6.11% respectively. It is indicated that CART model has not only better fitting and generalization ability, but also strong advantages in the analysis of landslide groundwater dynamic characteristics and the screening of important variables. It is an effective method for prediction of ground water level in landslides.

Description: Publication date: Available online 26 August 2016 Source: Geodesy and Geodynamics Author(s): Zhimin Liu, Yangyang Li, Jinyun Guo, Fei Li At present, Global Navigation Satellite Systems (GNSS) users usually eliminate the influence of ionospheric delay of the first order items by dual-frequency ionosphere-free combination. But there is still residual ionospheric delay error of higher order term. The influence of the higher-order ionospheric corrections on both GPS precision orbit determination and static Precise Point Positioning (PPP) are studied in this paper. The influence of higher-order corrections on GPS precision orbit determination, GPS observations and static PPP are analyzed by neglecting or considering the higher-order ionospheric corrections by using a globally distributed network which is composed of International GNSS Service (IGS) tracking stations. Numerical experimental results show that, the root mean square (RMS) in three dimensions of satellite orbit is 36.6 mm–35.5 mm. The maximal second-order ionospheric correction is 9 cm, and the maximal third-order ionospheric correction is 1 cm. Higher-order corrections are influenced by latitude and station distribution. PPP is within 3 mm in the directions of east and up. Furthermore, the impact is mainly visible in the direction of north, showing a southward migration trend, especially at the lower latitudes where the influence value is likely to be bigger than 3 mm.

Description: Publication date: Available online 7 June 2016 Source: Geodesy and Geodynamics Author(s): Ning Li, Lingyun Ji, Shuangxu Wang This study analyzes data regarding cross-fault deformations within the seismogenic zone of the 2016 Qinghai Menyuan M s6.4 earthquake and its surrounding area. The results showed that the tendency anomaly sites near the epicenter had relatively long anomaly durations prior to the earthquake, while sudden-jumping anomaly sites started to increase in the middle eastern Qilian Mountains approximately a year before the earthquake and continued to increase and migrate towards the vicinity of the epicenter two to six months before the earthquake. Intensive observations a few days after the earthquake indicated that abnormal returns and turns before the earthquake were significant, but all had small amplitudes, and the coseismic effect was generally minor. In addition, the post-seismic tendency analysis of individual cross faults in the Qilian Mountain fault zone revealed an accelerating thrust tendency at all cross-fault sites in the middle Qilian Mountains after the 2008 Wenchuan M s8.0 earthquake. This indicates that the Wenchuan mega-earthquake exerted a great impact on the dynamic environment of the northeastern margin of the Qinghai-Tibet plate and significantly enhanced the extrusion effect of the Indian plate on the middle Qilian Mountains, generating favorable conditions for the occurrence of Menyuan thrust earthquakes.

Description: Publication date: September 2016 Source: Journal of Hydrology: Regional Studies, Volume 7 Author(s): Donizete dos R. Pereira, Mauro A. Martinez, Fernando F. Pruski, Demetrius D. da Silva Study region The study was developed for fhe Pomba River Basin, which is located in southeast region of Brazil in the continent of South America. Study focus This study aimed to (a) calibrate and validate the SWAT model for a sub-basin of Pomba River Basin, (b) validate it for use with upstream and downstream control sections and (c) validate it for sub-basins other than the one where calibration was performed. This was done with the goal of having a model that can be used for the estimation of water availability and the planning of soil use and occupation. The model was calibrated by trial and error during the period from January 1996 through December 1999, while validation was conducted during the period from January 2000 through December 2004. Estimated the maximum, average and minimum annual daily streamflows were evaluated based on the paired t -test and linear regression analysis. New hydrological insights The SWAT model was qualified for simulating the Pomba River sub-basin in the sites where rainfall representation was reasonable to good. The model can be used in the simulation of maximum, average and minimum annual daily streamflow based on the paired t -test, contributing with the water resources management of region, although the model still needs to be improved, mainly in the representativeness of rainfall, to give better estimates of extreme values. Graphical abstract

Description: Publication date: Available online 10 June 2016 Source: Geodesy and Geodynamics Author(s): Chen Junyu, Sang Jizhang Atmospheric drag, which can be inferred from orbit information of low-Earth orbiting (LEO) satellites, provides a direct means of measuring mass density. The temporal resolution of derived mass density could be in the range from minutes to days, depending on the precision of the satellite orbit data. This paper presents two methods potentially being able to estimate thermosphere mass density from precise obit ephemeris with high temporal resolution. One method is based on the drag perturbation equation of the semi-major axis and the temporal resolution of retrieved density could be 150 s for CHAMP satellite. Another method generates corrections to densities computed from a baseline density model through a Kalman filter orbit drag coefficient determination (KFOD) process and the temporal resolution of derived density could be as high as 30 s for CHAMP satellite. The densities estimated from these two methods are compared with densities obtained from accelerometer data of CHAMP satellite. When the accelerometer data based densities are used as reference values, the mean relative accuracy of the densities derived from precision orbit data using the two methods is within approximately 10%. An application of the derived densities shows that the derived densities can reduce orbit predication errors.

Description: Publication date: Available online 14 June 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Mohammed Y. Fattah, Aysar H.S. Al-Lami Limited studies dealt with the expansive unsaturated soils in the case of large-scale model close to the field conditions and therefore, there is much more room for improvement. In this study, expansive (bentonite–sand (B-S) mixture) and non-expansive (kaolin) soils were tested in different water contents and dry unit weights chosen from the compaction curve to examine the effect of water content change on soil properties (swelling pressure, expansion indices, shear strength (soil cohesion) and soil suction) for the small soil samples. Large-scale model was also used to show the effect of water content change on different relations (swelling and suction with elapsed time). The study reveals that the initial soil conditions (water content and dry unit weight) affect the soil cohesion, suction and swelling, where all these parameters slightly decrease with the increase in soil water content especially on the wet side of optimum water content. The settlement of each soil at failure increases with the increase in soil degrees of saturation since the matric suction reduces the soil ability to deform. The settlement observed in B-S mixture is higher than that in kaolin due to the effect of higher swelling observed in B-S mixture and the huge amount of water absorbed which transformed the soil to highly compressible soil. The matric suction seems to decrease with elapsed time from top to bottom of tensiometers due to the effect of water flowing from top of the specimen. The tensiometer reading at first of the saturation process is lower than that at later period of saturation (for soil sample B-S3, the tensiometer #1 took 3 d to drop from 93 kPa to 80 kPa at early stage, while the same tensiometer took 2 d to drop from 60 kPa to 20 kPa).

Description: Publication date: Available online 27 May 2016 Source: Geodesy and Geodynamics Author(s): Zhicai Luo, Chaolong Yao, Qiong Li, Zhengkai Huang Time-variable gravity data from the Gravity Recovery and Climate Experiment (GRACE) satellite mission are used to study terrestrial water storage (TWS) changes over the Pearl River Basin (PRB) for the period 2003–Nov. 2014. TWS estimates from GRACE generally show good agreement with those from two hydrological models GLDAS and WGHM. But they show different capability of detecting significant TWS changes over the PRB. Among them, WGHM is likely to underestimate the seasonal variability of TWS, while GRACE detects long-term water depletions over the upper PRB as was done by hydrological models, and observes significant water increases around the Longtan Reservoir (LTR) due to water impoundment. The heavy drought in 2011 caused by the persistent precipitation deficit has resulted in extreme low surface runoff and water level of the LTR. Moreover, large variability of summer and autumn precipitation may easily trigger floods and droughts in the rainy season in the PRB, especially for summer, as a high correlation of 0.89 was found between precipitation and surface runoff. Generally, the PRB TWS was negatively correlated with El Niño-Southern Oscillation (ENSO) events. However, the modulation of the Pacific Decadal Oscillation (PDO) may impact this relationship, and the significant TWS anomaly was likely to occur in the peak of PDO phase as they agree well in both of the magnitude and timing of peaks. This indicates that GRACE-based TWS could be a valuable parameter for studying climatic influences in the PRB.

Description: Publication date: Available online 1 June 2016 Source: International Journal of Sustainable Built Environment Author(s): Pietro Picuno The recent increase in the sensitivity about the concept of sustainable development is stimulating the valorisation of the locally available material for agricultural construction, both for housing purpose and for some single components. This traditional building technique has indeed interesting consequences on the rural landscape perception - since the colour is similar to the countryside surroundings – as well as on the agricultural environment – this material being, at the end of its useful life, recyclable in the same context. Traditional material could be employed in other agricultural components, e.g. for food ageing, a technique used since Roman times, involving the use of earthenware amphorae, buried in the soil and used for storing wine and oil. In the present paper, the most diffused traditional building materials currently rediscovered are analysed, focusing on their utilization opportunities. One of the most interesting traditional construction material is the sun-dried earth brick, made of raw clay soil (so-called, “adobe”), often improved by the addition of fibers to control cracking while drying in the sun. After a general overview about the diffusion of earthen construction within agriculture, the results of experimental tests on adobe bricks reinforced with a natural fibre – Spanish Broom ( Spartium junceum L. ) – are reported.

Description: Publication date: Available online 1 June 2016 Source: Geodesy and Geodynamics Author(s): Qiong Li, Bo Zhong, Zhicai Luo, Chaolong Yao As critical component of hydrologic cycle, basin discharge is a key issue for understanding the hydrological and climatologic related to water and energy cycles. Combining GRACE gravity field models with ET from GLDAS models and precipitation from GPCP, discharge of the Yellow River basin are estimated from the water balance equation. While comparing the results with discharge from GLDAS model and in situ measurements, the results reveal that discharge from Mosaic and CLMGLDAS model can partially represent the river discharge and the discharge estimation from water balance equation could reflect the discharge from precipitation over the Yellow River basin.

Description: Publication date: Available online 3 June 2016 Source: Geodesy and Geodynamics Author(s): Haoming Yan, Yong Huang The wind stress acquired from European Centre for Medium-Range Weather Forecasts (ECMWF), National Centers for Environmental Prediction (NCEP) climate models and QSCAT satellite observations are analyzed by using frequency-wavenumber spectrum method. The spectrum of two climate models, i.e., ECMWF and NCEP, is similar for both 10 m wind data and model output wind stress data, which indicates that both the climate models capture the key feature of wind stress. While the QSCAT wind stress data shows the similar characteristics with the two climate models in both spectrum domain and the spatial distribution, but with a factor of approximately 1.25 times larger than that of climate models in energy. These differences show the uncertainty in the different wind stress products, which inevitably cause the atmospheric friction torque uncertainties on solid Earth with a 60% departure in annual amplitude, and furtherly affect the precise estimation of the Earth's rotation.

Description: Publication date: Available online 3 June 2016 Source: International Journal of Sustainable Built Environment Author(s): Oduyemi Olufolahan, Michael Iheoma Okoroh Sustainability has become a significant aspect of real estate and has been integrated into the design, construction and operation of buildings. Now, emerging from the various initiatives around the world, the building information modelling (BIM) approach has been seen as a method that might deliver substantial gains in terms of designing and assessing the environmental cost of buildings. Various research methodologies have been adopted, including literature review exploring the benefits and challenges of BIM and of using a building performance modelling software (BPM) called ECOTECT for sustainable building design. Finally, it introduces a design tool analysis of a case study using Ecotect to evaluate various what if scenarios on a proposed multi-use building. The output revealed that BPM delivers information needed for enhanced design and building performance. Recommendations such as the establishment of proper mechanisms to monitor the performance of BPM related construction are suggested to allow for its continuous implementation. This research consolidates collective movements towards wider implementation of BPM and forms a base for developing a sound BIM strategy and guidance.

Description: Publication date: Available online 4 June 2016 Source: International Journal of Sustainable Built Environment Author(s): Faiz Uddin Ahmed Shaikh This paper presents mechanical and durability properties of geopolymer concretes containing recycled coarse aggregate (RCA). The RCA is used as partial replacement of natural coarse aggregate (NCA) in geopolymer concretes at 15%, 30% and 50% by wt. which corresponds to second, third and fourth series, respectively. While the geopolymer concrete containing 100% NCA is control and is considered as the first series. Compressive strength, indirect tensile strength and elastic modulus of above geopolymer concretes are measured at 7 and 28 days, while sorptivity, immersed water absorption and volume of permeable voids of above geopolymer concretes are measured at 28 days. Results show that the compressive strength, indirect tensile strength and elastic modulus of geopolymer concretes decrease with increase in RCA contents, which is also true for both 7 and 28 days. The measured durability properties such as sorptivity, water absorption and volume of permeable voids of geopolymer concretes also adversely affected by the incorporation of RCA and these properties increase with increase in RCA contents.

Description: Publication date: September 2016 Source: Journal of Hydrology: Regional Studies, Volume 7 Author(s): Eliot A. Atekwana, Loago Molwalefhe, Oratile Kgaodi, Anna M. Cruse Study region Okavango Delta, Middle Kalahari, NW Botswana. Study focus We investigated the effect of evapotranspiration on the evolution of dissolved inorganic carbon (DIC) and stable carbon isotopes of DIC (δ 13 C DIC ) in the Okavango River. We measured the DIC concentrations and the δ 13 C DIC for samples collected over a 400 km reach of the river in the Okavango Delta during flood conditions and non-flood conditions. In addition, we incubated river samples collected from the proximal portion (Mohembo) and the distal portion (Maun) of the Delta and subsequently evaporated the samples by ∼90% under ambient conditions. New hydrological insights We found a 379% and 500% increase in the DIC concentrations and a δ 13 C DIC increase of 3.9‰ and 6.1‰ in the river during the flood non-flood conditions, respectively. The DIC concentrations of evaporated river samples increased by 535% for the Mohembo and by 850% for the Maun samples. The increase in the δ 13 C DIC of the evaporated river samples resulted from CO 2(g) loss during chemical equilibrium with atmospheric CO 2(g) followed by carbon exchange between DIC and atmospheric CO 2(g) . Although the δ 13 C DIC increased spatially for the Okavango River, it never reached the value of ∼0‰ expected for equilibration of river DIC with atmospheric CO 2(g) . The results of the evaporated river samples suggest that isotopic enrichment from equilibration in Okavango River was balanced by respiration and photo-oxidation of carbon-depleted dissolved organic matter.

Description: Publication date: Available online 2 June 2016 Source: International Journal of Sustainable Built Environment Author(s): G.M. Sadiqul Islam, Sristi Das Gupta Plastic concrete is susceptible to develop cracks due to shrinkage in dry and windy conditions. Addition of fibers could reduce propagation of this crack. On the other hand, permeability determines the durability properties of concrete. This study evaluated strength, plastic shrinkage and permeability (gas and water) of concrete incorporating ‘polypropylene’ fiber (aspect ratio 300) in various proportions (viz. 0.10%, 0.15%, 0.2%, 0.25% and 0.3%) by volume of concrete. Plane concrete samples were also prepared and tested for reference purpose. Inclusion of 0.1% fiber gave minor reduction (2%) in compressive strength while the tensile strength increased by 39% with same fiber content compared to the plain concrete. A significant reduction in crack generation, appearance period of first crack and crack area between plane concrete and fiber reinforced concretes were found. The experimental result with inclusion of 0.1-0.3% fiber in concrete indicated that plastic shrinkage cracks were reduced by 50-99% compared to the plain concrete. For reference concrete (without fiber), test within the high temperature and controlled humidity chamber gave higher crack width than the acceptable limit (3 mm) specified by the ACI 224. With the inclusion of 0.1% fiber reduced the crack width down to 1 mm and the trend was continued with the addition of more fibers. However, results showed that with the addition of polypropylene fiber both water and gas permeability coefficient was increased. Therefore, it is concluded that the fiber reinforced concrete would work better for plastic shrinkage susceptible structural elements (flat elements such as slab); however, it requires careful judgement while applying to a water retaining structures.

Description: Publication date: Available online 2 June 2016 Source: International Journal of Sustainable Built Environment Author(s): Susanne Bodach, Werner Lang It is predicted that the major increase of energy consumption and, thus, carbon emissions, will happen in the developing world. However, in most developing countries the knowledge about energy efficiency, particularly in the building sector, is quite low. Strategies developed for industrialised countries might not be suitable or must be adapted for the very different context of developing countries. This research aims to find energy-efficient and cost-effective building design options for the case of Nepal. Energy-efficient building design is a non-trivial issue involving a number of interdependent design criteria. Particularly, in composite climates, passive design strategies might conflict each other leading to an inefficient building design. This paper explores the energy conservation potential in hotel design for all bioclimatic zones of Nepal by using building energy simulation with parametric analysis. Based on an extensive field studies, reference models for typical hotel buildings ranging from small-scale resort hotels to large-scale multi-storey hotels were developed. These reference designs were optimised by varying design parameters such as window-to-wall ratio, glazing material, shading devices, glazing type and insulation levels. During the design optimisation, energy demand as well as cost effectiveness were evaluated. Finally, recommendations for energy-efficient and cost-effective hotel design solutions were suggested. In addition, the bioclimatic zoning for Nepal was consolidated leading to five elevation-based zones that can be used to introduce building energy regulations in the future.

Description: Publication date: Available online 2 June 2016 Source: International Journal of Sustainable Built Environment Author(s): Omprakash Sahu Sugarcane is valuable crop of India and have major role for foreign exchange. The aim of research work is to investigate the reduction of chemical oxygen demand and color from sugarcane industry effluent by thermolysis and coagulation method. The complete study was done in batch mode to determine the effect of operating parameters. The result shows maximum 73% of chemical oxygen demand and 76% color removal with copper oxide catalyst at 5Kg/m 3 massloading, 85°C reacting temperature, 9hrs treatment time and pH 8. Combined study shown 97.6% chemical oxygen demand and 99.9% color removal at pH 6.5 and mass loading 8mM with copper sulphate salt. The settling and filtration was found to be good at 65°C and 75°C with copper oxide treated sugar industry wastewater.

Description: Publication date: Available online 11 June 2016 Source: Geodesy and Geodynamics Author(s): Caijun Xu, Zheng Gong, Jieming Niu With the advanced development of the modern geodetic techniques, the geodetic observations have been proved to be more powerful to uncover the geophysical phenomena, especially the seismic one, than that in the past time. The recent developments and achievements in the seismological geodesy are summarised here. Several popular geodetic techniques, such as high-rate GNSS, InSAR and Satellite Gravimetry, are introduced first to present their recent contributions in studying the seismic deformations. The developments of the joint inversion of the seismic source parameters from multiple observations are then highlighted. Some outlooks in seismological geodesy are presented in the end.

Description: Publication date: Available online 14 June 2016 Source: Geodesy and Geodynamics Author(s): Leonid Zotov, C.H. Bizouard, C.K. Shum Using multichannel singular spectrum analysis (MSSA) we decomposed climatic time series into principal components, and compared them with Earth rotation parameters. The global warming trends were initially subtracted. Similar quasi 60 and 20 year periodic oscillations have been found in the global mean Earth temperature anomaly (HadCRUT4) and global mean sea level (GMSL). Similar cycles were also found in Earth rotation variation. Over the last 160 years multi-decadal change of Earth's rotation velocity is correlated with the 60-year temperature anomaly, and Chandler wobble envelope reproduces the form of the 60-year oscillation noticed in GMSL. The quasi 20-year oscillation observed in GMSL is correlated with the Chandler wobble excitation. So, we assume that Earth's rotation and climate indexes are connected. Despite of all the clues hinting this connection, no sound conclusion can be done as far as ocean circulation modelling is not able to correctly catch angular momentum of the oscillatory modes.

Description: Publication date: Available online 18 June 2016 Source: Geodesy and Geodynamics Author(s): Wei Feng, Jinwei Ren, Zaisen Jiang Continuous observation data from 24 GPS stations are selected in the area (33.0°N–41.0°N, 95.0°E–105.0°E) for this study (the period is from Jan. 1, 2015 to Jan. 20, 2016). Three components, NS, EW and UD, of the daily solutions are filtered by the Hilbert–Huang transform (HHT) with frequency band of 5.787 × 10 −7 –7.716 × 10 −8  Hz (20–150 days in period). And short-term dynamic characteristics of micro displacement before Menyuan M 6.4 earthquake are studied by using the temporal dependencies and cross spectrum analysis. The results show that before the earthquake the horizontal undulatory motions are higher than the average level in the series data which indicate the disturbance feature of regional stress before the earthquake. Three GPS stations on Qinghai-Tibet Plateau with their setting perpendicular to the seismogenic fault have consistent movement. The increase of amplitude of the horizontal micro motion observed before the quake is conducive to the earthquake occurrence. However, we could not be sure if the undulatory motion triggered the earthquake. It is quite necessary to build more GPS continuous observation stations and optimize the monitoring network so as to improve the understanding of the short-term dynamic crustal variation before earthquake.

Description: Publication date: Available online 17 September 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Zong-Xian Zhang Hanging roofs or high hang-ups, a common problem in sublevel caving mining, usually result in a large ore loss and undermine mining safety. This paper analyzed the formation of a hanging roof and showed that increased confining pressure and reduced free surface were its main characteristics. In order to break down a hanging roof, a new method based on shock wave collision and stress superposition was developed. In this method, two blastholes containing multi-primer at different positions are simultaneously initiated at first. By doing this, a new free surface and a swell room can be created. After these holes are fired, a long delay time is given to the next blasthole so that the fragments from the first two-hole blasting have enough time to fall down. This new method was applied to three hanging roofs in one production area, and all of them were successfully broken down. Field inspection indicated that almost no damage was caused in the nearby drifts/tunnels due to the new method. In addition, the far field vibrations were found to be smaller than the maximum vibrations induced by some other blasts.

Description: Publication date: Available online 20 September 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Bogdan Orlic In this paper, the geomechanical impact of large-scale carbon dioxide (CO 2 ) storage in depleted Dutch gas fields is compared with the impact of CO 2 storage in saline aquifers. The geomechanical behaviour of four potential CO 2 storage sites is examined using flow and geomechanical simulations. Many gas reservoirs in the Netherlands are found in fault blocks, one to a few kilometres wide, laterally bounded by sealing faults. Aquifer depletion or re-pressurization in the lateral direction is seldom an issue because of a lack of active aquifers. Reservoir pressure changes are therefore limited to a gas-bearing fault block, while the induced stress changes affect the gas reservoir and extend 1-3 km away into the surrounding rock. Arguments in favour of CO 2 storage in depleted gas fields are: proven seal quality, availability of field data, no record of seal integrity failure by fault reactivation from the seismically active producing Dutch gas fields, and the potential benefits of restoring the virgin formation pressure and stress state to geomechanical stability. On the other hand, CO 2 injection in saline aquifers causes pressure build-up that exceeds the virgin hydrostatic pressure. Stress perturbations resulting from pressure build-up affect large areas, extending tens of kilometres away from the injection wells. Induced stresses in top seals are, however, small and do not exceed a few tenths of megapascal for a pressure build-up of a few megapascals in the storage formation. Geomechanical effects on top seals are weak, but could be enhanced close to the injection zone by the thermal effects of injection. Uncertainties related to characterisation of large areas affected by pressure build-up are significant, and seal quality and continuity are more difficult to be demonstrated for aquifers than for depleted gas reservoirs that have held hydrocarbons for millions of years.

Description: Publication date: Available online 31 August 2016 Source: International Journal of Sustainable Built Environment Author(s): Indira Parajuli, Heekwan Lee, Krishna Raj Shrestha Cooking with open fire has been a crucial for occupants’ health due to poor Indoor Air Quality (IAQ) in most of the rural households. IAQ is affected by many factors, such as firewood moisture,stove type, ventilation, etc. A monitoring system has been developed to find the general IAQ with Improved Cooking Stove (ICS) and Traditional Cooking Stove (TCS). Decay curve technique is utilized to calculate the Carbon Monoxide (CO) decay time. A preliminary health survey is also carried out to evaluate the dweller’s health complaints. The study is carried out in two adjoining remote villages of Palpa District in Western Nepal. The mean CO and PM 2.5 concentration for ICS and TCS are 27.11ppm and 825.4μg/m3 (27.11±14.24ppm and 825.4±730.9μg/m3) with significant correlation (p〈0.0001) and 36.03ppm and 1336μg/m 3 (36.03±19.06 and 1336±952.8) with significant correlation (p〈0.0481), respectively. From the overall sample, the mean CO and PM2.5 concentration is reduced by 29.9% and 39%, respectively. The ventilation analysis result shows more than an 80 percentage deficit in ventilation as per the minimal rate of ventilation as prescribed by American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). Moreover, the placement of chimney at a short vertical height of 1.2m adjoining to back window is the major cause of backflow. Therefore, the study has recommended a greater focus on ventilation to control IAQ of rural mountainous households.

Description: Publication date: Available online 31 August 2016 Source: International Journal of Sustainable Built Environment Author(s): Sudha Panda, Manjari Chakraborty, SK Misra India has experienced rapid urbanization with the rate growing from 26 percent in the 1990-2000 decade, to 30 percent in the 2000-2010 decade putting massive pressure on basic infrastructure and services. The objective of this paper is to develop a social sustainable framework and a composite index which is tailor-made to assess the Indian cities. Since social sustainability cannot be developed in isolation this paper examines urban sustainability in an integrated manner with its four dimensions of social, economic, environmental and institutional and maps the criteria at three levels i.e. policy, theoretical, and practical levels. The three tiered hierarchical model is tested in the state of Odisha where the social sustainability can be put to test in the best context as the urbanization is growing at a stupendous speed and the infrastructure growth does not match up. Using the framework it is possible to obtain a composite index for urban social sustainability whose model can be applied to all Indian cities with contextual changes. The dimensional index score and thematic index score obtained from the model helps in benchmarking the cities and identifying gaps so that it can inform national policy and planning .The social sustainability index together with the indices on the other three dimensions would help in making well informed judgement in the allocation of resources.

Description: Publication date: Available online 25 August 2016 Source: Geodesy and Geodynamics Author(s): Yuan Li, Yannan Zhao, Zhengliang Lin, Qinlin Ma The Fushan Depression is a half-graben rifted sub-basin located in the southeast of the Beibuwan Basin, South China Sea. The Paleogene Liushagang sequence is the main hydrocarbon-bearing stratigraphic unit in the sub-basin. Using three-dimensional (3-D) seismic data and logging data over the sub-basin, we analyzed structural styles and sedimentary characteristics of the Liushagang sequence. Five types of structural styles were defined: ancient horst, traditional slope, flexure slope-break, faulted slope-break and multiple-stage faults slope, and interpretations for positions, background and development formations of each structural style were discussed. Structural framework across the sub-basin reveals that the most remarkable tectonic setting is represented by the central transfer zone (CTZ) which divides the sub-basin into two independent depressions, and two kinds of sequence architectures are summarized: (i) the western multi-stage faults slope; (ii) the eastern flexure slope break belt. Combined with regional stress field of the Fushan Depression, we got plane combinations of the faults, and finally built up plan distribution maps of structural system for main sequence. Also, we discussed the controlling factors mainly focused on subsidence history and background tectonic activities such as volcanic activity and earthquakes. The analysis of structural styles and tectonic evolution provides strong theoretical support for future prospecting in the Fushan sub-basin and other similar rifted basins of the Beibuwan Basin in South China Sea.

Description: Publication date: Available online 26 August 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Zhongkui Li, Baoqi Lu, Jing Zou, Bin Xu, Zhizeng Zhang The underground water-sealed storage technique is critically important and generally accepted for the national energy strategy in China. Although several small underground water-sealed oil storage caverns have been built in China since the 1970s, there is still a lack of experience for large-volume underground storage in complicated geological conditions. The current design concept of water curtain system and the technical instruction for system operation have limitations in maintaining the stability of surrounding rock mass during the construction of the main storage caverns, as well as the long-term stability. Although several large-scale underground oil storage projects are under construction at present in China, the design concepts and construction methods, especially for the water curtain system, are mainly based on the ideal porosity medium flow theory and the experiences gained from the similar projects overseas. The storage projects currently constructed in China have the specific features such as huge scale, large depth, multiple-level arrangement, high seepage pressure, complicated geological conditions, and high in situ stresses, which are the challenging issues for the stability of the storage caverns. Based on years’ experiences obtained from the first large-scale (millions of cubic meters) underground water-sealed oil storage project in China, some design and operation problems related to water curtain system during project construction are discussed. The drawbacks and merits of the water curtain system are also presented. As an example, the conventional concept of “filling joints with water” is widely used in many cases, as a basic concept for the design of the water curtain system, but it is immature. In this paper, the advantages and disadvantages of the conventional concept are pointed out, with respect to the long-term stability as well as the safety of construction of storage caverns. Finally, new concepts and principles for design and construction of the underground water-sealed oil storage caverns are proposed.

Description: Publication date: Available online 29 August 2016 Source: Journal of Rock Mechanics and Geotechnical Engineering Author(s): Yueping Yin, Bolin Huang, Wenpei Wang, Yunjie Wei, Xiaohan Ma, Fei Ma, Changjun Zhao The Three Gorges region in China was basically a geohazard-prone area prior to construction of the Three Gorges Reservoir (TGR). After construction of the TGR, the water level was raised from 70 m to 175 m above sea level (ASL), and annual reservoir regulation has caused a 30-m water level difference after impoundment of the TGR since September 2008. This paper first presents the spatiotemporal distribution of landslides in six periods of 175 m ASL trial impoundments from 2008 to 2014. The results show that the number of landslides sharply decreased from 273 at the initial stage to less than ten at the second stage of impoundment. Based on this, the reservoir-induced landslides in the TGR region can be roughly classified into five failure patterns, i.e. accumulation landslide, dip-slope landslide, reversed bedding landslide, rockfall, and karst breccia landslide. The accumulation landslides and dip-slope landslides account for more than 90%. Taking the Shuping accumulation landslide (a sliding mass volume of 20.7 × 10 6 m 3 ) in Zigui County and the Outang dip-slope landslide (a sliding mass volume of about 90 × 10 6 m 3 ) in Fengjie County as two typical cases, the mechanisms of reactivation of the two landslides are analyzed. The monitoring data and factor of safety (FOS) calculation show that the accumulation landslide is dominated by water level variation in the reservoir as most part of the mass body is under 175 m ASL, and the dip-slope landslide is controlled by the coupling effect of reservoir water level variation and precipitation as an extensive recharge area of rainfall from the rear and the front mass is below 175 m ASL. The characteristics of landslide-induced impulsive wave hazards after and before reservoir impoundment are studied, and the probability of occurrence of a landslide-induced impulsive wave hazard has increased in the reservoir region. Simulation results of the Ganjingzi landslide in Wushan County indicate the strong relationship between landslide-induced surge and water variation with high potential risk to shipping and residential areas. Regarding reservoir regulation in TGR when using a single index, i.e. 1-d water level variation, water resources are not well utilized, and there is also potential risk of disasters since 2008. In addition, various indices such as 1-d, 5-d, and 10-d water level variations are proposed for reservoir regulation. Finally, taking reservoir-induced landslides in June 2015 for example, the feasibility of the optimizing indices of water level variations is verified.

Description: Publication date: Available online 10 May 2016 Source: International Journal of Sustainable Built Environment Author(s): Manoj Kumar Dash, Sanjaya Kumar Patro, Ashoke Kumar Rath Utilization of industrial waste materials in concrete compensates the lack of natural resources, solving the disposal problem of waste and to find alternative technique to safeguard the nature. There are number of industrial wastes used as fully or partial replacement of coarse aggregate or fine aggregate. This review carries out a thorough assessment about industrial waste substances, which can be adequately utilized in concrete as fine aggregate substitution. This paper reviewed some of these industrial wastes like waste foundry sand, steel slag, copper slag, imperial smelting furnace slag (ISF slag), blast furnace slag, coal bottom ash, ferrochrome slag and palm oil clinker etc. Out of these materials, maximum number of experiments have been conducted by using waste foundry sand and copper slag as fine aggregate replacement, but still more examinations are required for other waste materials as replacement of sand in concrete. Different physical and mechanical properties of industrial waste as well as of industrial waste concrete, in which natural sand is substituted has been reviewed and comparison are made between them. Deflection and leaching study review are carried out additionally and compared. It can be observed that the concrete where sand is replaced by copper slag, imperial smelting furnace slag, class F fly ash exhibits improved strength and durability properties, but it’s slump increases as the rate of replacement increases in case of copper slag and the slump decreases in the case of class F fly ash. There is a less research work reported on ferrochrome slag and palm oil clinker used as sand substitution, so it is felt that further detailed investigations are required.

Description: Publication date: Available online 27 May 2016 Source: Geodesy and Geodynamics Author(s): Wenbin Shen, Cunchao Peng Scientists pay great attention to different-time-scale signals in the length of day (LOD) variations ΔLOD, which provide signatures of the Earth's interior structure, couplings among different layers, and potential excitations of ocean and atmosphere. In this study, based on the ensemble empirical mode decomposition (EEMD), we analyzed the latest time series of ΔLOD data spanning from January 1962 to March 2015. We observed the signals with periods and amplitudes of about 0.5 month and 0.19 ms, 1.0 month and 0.19 ms, 0.5 yr and 0.22 ms, 1.0 yr and 0.18 ms, 2.28 yr and 0.03 ms, 5.48 yr and 0.05 ms, respectively, in coincidence with the results of predecessors. In addition, some signals that were previously not definitely observed by predecessors were detected in this study, with periods and amplitudes of 9.13 d and 0.12 ms, 13.69 yr and 0.10 ms, respectively. The mechanisms of the LOD fluctuations of these two signals are still open.

Description: Publication date: December 2016 Source: Journal of Hydrology: Regional Studies, Volume 5, Supplement 1 Author(s): Anonymous

Description: Publication date: December 2016 Source: Journal of Hydrology: Regional Studies, Volume 5, Supplement 1 Author(s): Anonymous

Description: Publication date: December 2016 Source: Journal of Hydrology: Regional Studies, Volume 5, Supplement 1 Author(s): Anonymous

Description: Publication date: December 2016 Source: Journal of Hydrology: Regional Studies, Volume 5, Supplement 1 Author(s): Anonymous

Description: Publication date: December 2016 Source: Journal of Hydrology: Regional Studies, Volume 5, Supplement 1 Author(s): Anonymous

Description: Publication date: December 2016 Source: Journal of Hydrology: Regional Studies, Volume 5, Supplement 1 Author(s): Anonymous

Description: Publication date: December 2016 Source: Journal of Hydrology: Regional Studies, Volume 5, Supplement 1 Author(s): Anonymous

Description: Publication date: December 2016 Source: Journal of Hydrology: Regional Studies, Volume 5, Supplement 1 Author(s): Anonymous

Description: Publication date: December 2016 Source: Journal of Hydrology: Regional Studies, Volume 5, Supplement 1 Author(s): Baohong Ding

Description: Publication date: December 2016 Source: Journal of Hydrology: Regional Studies, Volume 5, Supplement 1 Author(s): Evangelos Tziritis

Description: Publication date: December 2016 Source: Journal of Hydrology: Regional Studies, Volume 5, Supplement 1 Author(s): Anonymous

Description: Publication date: December 2016 Source: Journal of Hydrology: Regional Studies, Volume 5, Supplement 1 Author(s): Lineu Rodrigues