Giuseppe Mandrone

Structural Data Treatment to Define Rockfall Susceptibility Using Long Range Laser Scanner

Laser scanning techniques are nowadays more and more used in engineering geology in order to assess slope stability. In this study it is described an application of a new Terrestrial Laser Scanner that offers an extremely long measurement range and the procedure applied in geologic data treatment. Point cloud, 3D models, “solid images” and DEM generated from Terrestrial Laser Scanner survey were managed with Ad Hoc, a software platform with specific tools for geologic and geomechanic analysis. The assessment of rockfall prone area has been developed according to two approaches: deterministic and empirical. In the first case the detection of potentially unstable blocks, typically done with field surveys in case of outcrops of limited extension, were performed directly on the point cloud and on solid images. In the second case GIS tools were used allowing to apply the geomechanic classification SMR Romana for each pixel. Results obtained from both approaches is compared as a further data validation procedure.

A case study on the application of destructive and non-destructive methods for evaluating jet-grouting column integrity for bridge-pier scour protection (Cuneo, NW Italy)

A case study on the use of direct and indirect investigations for the effectiveness evaluation of jet-grouting interventions for bridge scour protection is presented. The major concern of this scour countermeasure is that a reliable verification and imaging of the exact dimensions and shape of the grouted elements and their related strength and integrity are difficult to obtain. An integrated cost-effective and slightly invasive approach, by means of indirect surveys, is proposed in this work to limit re-drilling and core sampling of jet columns. Tests are performed on a bridge located in the Province of Cuneo (NW Italy). On site, active fluvial activity was scouring four of the 19 bridge piers and jet-grouting interventions were designed to prevent bridge collapse. A dual approach was consequently applied to evaluate the goodness of jet-grouting treatments: results of direct tests (visual and mechanical characterization of core drillings, with Point Load and Uniaxial Compressive Strength tests) have been compared to indirect investigations (seismic down-hole tests and 2-D cross-hole tomography, laboratory Ultrasonic Pulse Velocity measurements). All the techniques showed potentiality in identifying variations of the jet-grouting properties within the columns. Generally, worsening in jet-grouting properties was coherently identified by a decrease in the seismic velocities and in the mechanical parameters and confirmed by visual inspection of core drillings. Local anomalies and discrepancies between the adopted method were however highlighted and critically discussed as a function of the limitations, disturbances and investigated volumes of each method.

An Integrated Approach for Monitoring Slow Deformations Preceding Dynamic Failure in Rock Slopes: A Preliminary Study

Rock slope monitoring is a major aim in territorial risk assessment and mitigation. The high velocity that usually characterizes the failure phase of rock instabilities makes the traditional instruments based on slope deformation measurements not applicable for early warning systems. On the other hand the use of acoustic emission records has been often a good tool in underground mining for slope monitoring. In this paper the design and installation of a monitoring system based on acoustic emission aimed at interpret and forecast a large rock instability phenomenon is reported together with some preliminary geophysical and geomechanical studies performed.

New Perspectives in Long Range Laser Scanner Survey Focus on Structural Data Treatment to Define Rockfall Susceptibility

Laser scanning techniques are nowadays more and more used in engineering geology in order to describe slope instability assessment. In this study it is described an application of a new Terrestrial Laser Scanner that offers an extremely long measurement range and the procedure applied for geological data treatment. Point cloud, 3D models, “solid images” and DEM generated from Terrestrial Laser Scanner survey were managed with Ad Hoc, a software platform with specific tools for geological and geomechanic analysis.

G.TES: Pilot Plant for Seasonal Ground Energy Storage in Italy

Ground heat storage is considered a powerful solution for supplying thermal energy for heating and cooling (H&C) demand in buildings, covering the energy demand using the ground as a heat reservoir. The Turin University set up a test site at the Campus of Grugliasco in which this method is being tested at a real scale. Apart from direct temperature measurements in the ground and in different part of the hydraulic circuit, a laboratory scale modeling and a numerical simulation are being carried out as well as some direct measurements on the involved geological materials. All the measurements are targeted to the determination of physical parameters of soil, to the quantification of storable heat but also to the evaluation of environmental impact of the whole system. This experiment will allow in the near future a better design of seasonal ground storage facility in northern Italy.

A Ready to Use GRASS GIS Workbench for Rockfall Analysis

Open Source software is of great interest to many users and developers. One of the main advantages is that users can develop and adapt it to suit their purposes. This work shows modules developed into GRASS GIS for rockfall analysis. Modules examine both the potential failure detection (rockfall susceptibility) and the area of potential propagation. The study investigate three different mechanisms of failure: planar sliding, wedge sliding and toppling. The modules for rockfall susceptibility are called r.SMR, r.SSPC, r.fsplanar, r.wedgeSMR and r.wedgeSSPC according to the method of analysis adopted, while r.droka is the name of the module developed for the propagation of the landslide. Input data are both numbers and raster maps. GIS modules have been tested with good results in Ossola Valley and, in general, they should be applied in geological settings where the failure mechanism is mainly governed by discontinuity sets.