Capturing cyclic mobility and preloading effects in sand using a memory-surface hardening model

Earthquake-induced build-up of pore water pressure may be responsible for reduced soil capacity, while the accumulation of shear strains may lead to a violation of serviceability limits. Predicting accurately the soil cyclic behaviour in relation to seismic numerical simulations is still a challenging topic in many respects. Efforts are required to improve several technical aspects, including the development of a reliable and complete constitutive model. This paper reports recent developments after the work of Liu et al. (2018a), and particularly about the performance of a new SANISAND formulation incorporating the memory surface concept (Corti et al., 2016). The performance of the model in terms of strain accumulation and pore pressure build-up is validated against high-quality laboratory test results. A modified dilatancy relationship is given to reproduce within the proposed framework proper cyclic mobility response. The effects of preliminary drained cyclic preloading on soil liquefaction resistance are also studied. © 2019 Associazione Geotecnica Italiana, Rome, Italy.