Class-C Simulations of LEAP-ASIA-2019 via OpenSees Platform by Using a Pressure Dependent Multi-yield Surface Model

Abstract

AbstractIn this chapter, Class-C numerical simulations were performed for LEAP-ASIA-2019 centrifuge experiments that took place at different universities testing facilities. A comparative study was conducted among the simulated and experimental seismic responses of a mildly sloping ground of medium-dense to dense Ottawa-F65 sand under ramped sinusoidal acceleration input motions. A pressure dependent multi-yield surface model that can simulate the liquefaction potential of sand soils under earthquake loading was chosen for the numerical simulations through the OpenSees finite element modeling software. An initial calibration of the soil constitutive model, namely “Phase I,” was performed against different cyclic torsional shear tests for Ottawa-F65 sand under various Cyclic Stress Ratios (CSRs). Numerical modeling of centrifuge experiments “Phase II” was carried out after a few adjustments to the estimated model parameter values for the sake of providing proper computed output responses. The adopted soil model and simulation technique provide adequate numerical predictions of the liquefaction potential for the mildly sloping ground problem and accurately simulate the time histories of excess pore water pressure, accelerations, and surface deformations, regardless of experiencing a few undesirable responses for simulated Kyoto University centrifuge tests. The capabilities and limitations of the selected constitutive soil model and computational technique are analyzed and discussed through the context.