Abstract:

A cyclic horizontal displacement solution of subsoil is of great concern in aseismic design of foundations and underground structures. Herein a double-layer model is adopted to simulate horizontal strata and to provide a theoretical simplified displacement solution in frequency domain which considers an existing liquefiable soil layer. Meanwhile, the relevant displacement of subsoil under arbitrary loading in time domain is also presented by the cycle-by-cycle method. Using a proper porewater pressure incremental model for horizontal soil strata, the moduli of subsoil is updated cycle by cycle to simulate the nonlinear process of subsoil caused by liquefaction. The results of shaking table test are consistent with the calculated results. It is shown that the method proposed can describe the process of liquefaction fundamental influence on subsoil displacement. The proposed method which is of clear physical meaning can represent the basic model of influence of liquefaction on subsoil displacement; and it can be used for non-dimensional analysis in time and frequency domains.

Key words: liquefaction, displacement, horizontal strata, theoretical solution