On the use of elasto-plastic models with hardening for excavations on the gravel of Lima

In recent years, the construction of large buildings has increased in the city of Lima, mainly for homes and offices. This in turn, has brought about the need to generate more space vehicles parking. Consequently, it is necessary to carry out excavations of greater depth, which very often exceeds 30m. The construction of these excavations requires specialized support systems, whose objective is to guarantee the stability of the excavation and limit the level of deformations that may occur as a result of the excavation. Anchored walls are the preferred system in Peru, which are mainly designed by limit equilibrium analysis. However, some accidents have been reported recently which has forced the revision of the methods of design, including those using FEM. The main limitation for the use of FEM is that more research is required in relation to the geotechnical parameters of the Lima gravel. This paper presents a review of the available parameters for the gravel soil of Lima, as a result of large scale in situ tests analysis and backanalysis of excavations, in relation to an elasto-plastic model with hardening, highlighting its advantages over the conventional Mohr-Coulomb model for excavation projects in gravels.