Terrestrial laser scanning for rockfall stability analysis in the cultural heritage site of Pitigliano (Italy)

Abstract

Traditional surveying methods are often not sufficient to achieve a complete geomechanical characterization of the rock mass, to analyze the instability mechanisms threatening the cultural heritage of hilltop historic towns. In Pitigliano (Tuscany, Central Italy), terrestrial laser scanning was employed complementarily to conventional geomechanical techniques. The overall 3D survey of the exposed surfaces was combined with scanlines of the inner walls of the subterranean cavities running underneath the historic centre. The rock mass discontinuities geometry was extracted, and the most critical instability mechanisms were mapped, with particular interest in the potential impacts on the ancient buildings located along the cliff edge. The geomechanical analysis of the surveyed joint sets confirmed a structural control on the cliff morphology by two main joint sets. Thanks to the laser scanner-based kinematic analysis, flexural toppling and wedge failure were found as the main hazardous instability mechanisms in Pitigliano. Finally, the conservation criticalities were identified and a pilot monitoring system was installed in a sector highly susceptible to block detachment.

A Comparison of Simulated Annealing, Genetic Algorithm and Particle Swarm Optimization in Optimal First-Order Design of Indoor TLS Networks

“…Engineering surveying, as topographical surveying (Lague et al, 2013), civil engineering surveying (Oskouie et al, 2016), deformation monitoring (Mukupa et al, 2016), and complex industrial equipment modelling (Son, 2014); 2. Architecture reconstruction (Santagati et al, 2013), heritage documentation and preservation (Fanti et al, 2013); 3. Environmental monitoring and disaster prevention (Abellán et al, 2014).…”

A method for assessing and managing landslide residual hazard in urban areas

“…In Italy, historical settlements are often built on hilltops suffering from stability issues, therefore requiring the implementation of monitoring systems, as well as expensive maintenance and restoration works (Ciampalini et al 2012;. In the last two decades, amongst the many new methods used in landslide investigation, terrestrial-based technologies such as digital photogrammetry (Zhang et al 2004;Sturzenegger and Stead 2009), light detection and ranging (LiDAR; Oppikofer et al 2009;Fanti et al 2013), infrared thermography (Gigli et al 2014a, b;Frodella et al 2015), and groundbased radar interferometry (GB-InSAR) (Luzi et al 2004;Lombardi et al 2016) are increasingly being recognized as efficient remote surveying techniques for the characterization and monitoring of landslide-affected areas, in terms of resolution, accuracy, data visualization, management and reproducibility. GB-InSAR systems in particular, for their capability of measuring displacements with high geometric accuracy, temporal sampling frequency and adaptability to specific applications (Monserrat et al 2014), represent powerful devices successfully employed in engineering and geological applications for detecting structural deformation and surface ground displacements (Tarchi et al 2003;Antonello et al 2004;Casagli et al 2010Casagli et al , 2017, for the monitoring of volcanic activity (Di Traglia et al 2014a, b), and for analysing the stability of historical towns built on hilltops (Luzi et al 2004;Nolesini et al 2016).…”

The Calatabiano landslide (southern Italy): preliminary GB-InSAR monitoring data and remote 3D mapping

“…In recent years, the Ground-Based Interferometric Synthetic Aperture Radar (GB-InSAR) technique has been widely used to monitor ground displacements in research on landslides (Tarchi et al, 2003;Herrera et al 2009;Barla et al 2010;Schulz et al 2012;Corsini et al 2013;Bardi et al 2014), volcanoes (Bozzano et al 2011;Nolesini et al, 2013;Di Traglia et al 2014) and sinkholes (Intrieri et al 2015). Terrestrial laser scanning (TLS) has become a widely applied technique for the detection and characterization of several types of mass movements as it allows the rapid collection of detailed and highly accurate 3D ground representations (Abellan et al 2006;Oppikofer et al 2008;Jaboyedoff et al 2009;Fanti et al 2012;Gigli et al 2014). The intrinsic characteristics of the abovementioned techniques, such as (i) producing near-real-time displacement maps without physical access to the analysed area; (ii) observing the investigated scenario 24 h per day and in all weather conditions; (iii) generating high-resolution images, especially for analysis of local-scale phenomena; and (iv) providing high versatility and transportability, represent consistent advantages with respect to traditional methods.…”