ALBERT

Description: This research work analyses the influence of the use of by-products from a fluorite mine to replace the fine fraction of natural aggregates, on the properties of Ultra-High-Performance Fibre-Reinforced Concrete (UHPFRC). Replacing natural aggregates for different kinds of wastes is becoming common in concrete manufacturing and there are a number of studies into the use of waste from the construction sector in UHPFRC. However, there is very little work concerning the use of waste from the mining industry. Furthermore, most of the existing studies focus on granite wastes. So, using mining sand waste is an innovative alternative to replace natural aggregates in the manufacture of UHPFRC. The substitutions in this study are of 50%, 70% and 100% by volume of 0–0.5 mm natural silica sand. The results obtained show that the variations in the properties of consistency, compressive strength, modulus of elasticity and tensile strength, among others, are acceptable for substitutions of up to 70%. Therefore, fluorite mining sand waste is proved to be a viable alternative in the manufacturing of UHPFRC.

Description: Studies of the elements that make up the structure of a building have generally focused on topics related to their physical and structural capacities. Although research has been carried out into environmental impact during the life cycle stages, the environmental profile is far from established. This research aims to reduce the gap in the knowledge of this subject, offering useful information to professionals in the construction industry, which will enable them to consider environmental aspects when choosing the best construction systems. The present study applies the methodology of the life cycle assessment (LCA), to analyze and compare four floor construction systems in two different scenarios (“A” with a functional homogeneous unit of 1 m2 and “B” with 1 m² made up of the percentages of the floor system and the special areas of the building). The analysis is performed using the LCA Manager software, along with the Ecoinvent 3.1 database and with a cradle to handover perspective (A1–A5). Comparison was made using two environmental impact methodologies, Eco-indicator 99 and CML 2001. The results highlight the stages A1–A3 as those that generate the greatest environmental impact. Comparing the environmental profiles of the different floor systems, one-way floor systems I and II had the best environmental scores, 30% less than two-way floor system III and 50% less than slab floor system IV.