Objective 1: Explicit identification of unstable rock volumes and stability assessment

The experience gained form the Rockrisk project has proven that, with the combined use of LIDAR and digital photogrammetry, it is possible to identify and georeferenciate all the discontinuities present in the rock mass, taking into account the orientation and the real spacing. Having achieved this, makes it possible to perform stability analysis of rock edges and kinematic moving rock volumes, establishing with precision which are the possible failure surfaces and helping with the quantification of rock bridges.

In the Rockrisk project we have defined the loosen rock volumes in the recent toppling, with great accuracy, through the comparison of the Digital Surface Model (DSM) before and after failure. (Ruiz-Carulla et al., 2015). The fundamental limitation of this approximation is the assumed infinite persistence of the joints and, as a consequence, outside of the particular cases, as failures developed through strata, the computed volumes are greater than the real ones.

Objective 1a. Analysis of the visible traces of the discontinuities of the rock edges and individual blocks, by means of LiDAR and digital photogrammetry and their relationship with the persistence of the joints and the proportion of rock bridges present in the mass.

Objective 1b. Quantify the contribution of partially penetrating joints and rock bridges in the resistance and stability of rock masses in escarpments, through the retrospective analysis of failures in which previously (objective 1a) we will have quantified the percentage of joints and intact rock.