FDEM analysis of fracturing processes affecting vertical cliffs in soft calcarenites

The stability of soft rock cliffs can be treated nowadays by using advanced calculation techniques, as the hybrid FDEM approach, which are capable of simulating rock fragmentation processes owing to post-failure material brittleness. In order to assess the stability of cliffs in soft rocks, modelling approach should take directly into account the processes of material detachment, shear sliding as well as crack opening and propagation. This work is aimed at highlighting the role of post-peak brittleness in sea cliff stability problems involving soft calcarenites by means of the application of a hybrid finite-discrete element method. In particular, the paper presents the simulations performed for an ideal vertical cliff formed of soft calcarenites outcropping in Southern Italy, with regard to a couple of factors, namely the influence of the depth of sea erosion at the toe of the cliff and the role of strength degradation of the calcarenite as an effect of the environmental weathering which is particularly intense along the coastal cliffs.