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The GeoRisk project, reference PID2019-103974RB-I00 is funded by MCIN/ AEI/10.13039/501100011033.

Improvement and performance of the QRA for rockfalls

The availability of new geomatic techniques allows new challenges in rockfall susceptibility and hazard assessment to be addressed. We will focus on three issues that have a direct effect on the occurrence of rockfalls and their propagation: generation/source areas, magnitude frequency relation and trajectory definition. Therefore, the objectives are:

On the other hand, data for the spatial and temporal exposure of potentially affected elements and their vulnerability will be gathered and integrated using knowledge-driven approaches to assess the risk, using Expected Value (EV) formulations (average annual loss), and further social and individual risk descriptors. Given the complexity and diverse focus that the QRA procedure requires depending on the type of the exposed elements, this project will focus on lineal infrastructures, mainly on people and vehicles...

Image from Matas (2020)

In various cases of rockfall events, the trajectories of the rock blocks are affected by the presence of natural (trees) or artificial (mitigation substructures such as barriers, walls…) obstacles. The stopping distance of the blocks or their direction varies according to parameters such as the impact energy and height on the obstacle, the number of moving blocks etc...For this project the aim is to incorporate in the analysis the presence of different kind of protection measures and other elements that will be modelled as an obstacles, which are, in practice, the most common: dynamic barriers (highly deformable); rigid barriers (concrete walls, or walls composed by vertical rails or beams; other wall typologies including the façades of buildings in the propagation path); earthworks (dikes, earthfills, catchment ditchs); trees or forest areas...

The goal is to feed into the analysis new algorithms, which are missing from current models, and that integrate all significant aspects of the rockfall process, from the source, to the fragmentation and impact on obstacles, up to the lower areas where the QRA takes place.