Publication Date:
2020-12-21
Description:
The use of Non-Destructive Testing (NDT) applied
to construction materials allows to highlight and characterize
their features, especially in the case of old buildings.
The multi-technique high resolution 3D modelling described
here is aimed to investigate the conservation state of the central
column of a colonnade in the ancient church of Saints
Lorenzo and Pancratio, dating to about the second half of
the thirteenth century and located in the old town of Cagliari
(Italy). This column was considered of interest because its
longitudinal axis deviates from its ideal position and it appears
the most deteriorated.
In this work we describe the integrated application of
3D diagnostic methods, i.e. Terrestrial Laser Scanner (TLS),
close range photogrammetry (CRP) and ultrasonic tomography
supported by petrographic investigations. They were
used to improve the diagnostic process of the conservation
state of the investigated column. The TLS technique was supported
by CRP to obtain a natural colour texturized 3D model
of the column. The geometrical anomaly maps derived from
the data of the TLS-CRP survey show the presence of some
anomalies worthy of attention. Starting from the 3D reconstruction
with previous techniques we planned and implemented
a 3D ultrasonic tomography. Ultrasonic tomography
proved to be a successful tool in identifying internal defects,
as well as the presence of voids and flaws within the materials
through the analysis of the propagation of ultrasonic
waves.
The integration of the three non-invasive techniques supported
by petrographical analyses demonstrates its potential
in reducing ambiguities since each technique brings its clue
to the overall diagnostic process.
Description:
Published
Description:
119-127
Description:
5T. Sismologia, geofisica e geologia per l'ingegneria sismica
Description:
JCR Journal
Keywords:
3D Modelling
;
Non-Destructive Testing
;
3D Diagnostic Methods
;
Terrestrial Laser Scanner
;
Close Range Photogrammetry
;
Ultrasonic Tomography
;
Petrographic Investigations
;
Integrated Application
;
Solid Earth
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
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