An advanced numerical approach to optimise the construction stages of an earth dam resting on fine grained strata

This paper describes a FE coupled approach to evaluate the behaviour of the foundation of an earth dam during the construction stages. The subsoil of the site under study is characterised by heterogeneous materials, including a shallow fine grained stratum of low strength. The foundation strata are modelled by means of a single potential constitutive model recently implemented by the Authors in the FE code Plaxis, capable of describing the dependency of the elastic stiffness on the state of stress and the occurrence of structure degradation processes under engineering loads. The numerical analyses highlight the progressive increment in the available shear strength of the fine grained subsoil during the construction of the dam, due to the ongoing consolidation process, such that both short and long term stability conditions are satisfied, differently from what indicated by more conventional analysis approaches.