NUMERICAL ANALYSIS OF FREE FIELD SYSTEM IN LIQUEFIABLE SITE AND VALIDATION OF SHAKING TABLE TESTS
LU Xilin1，REN Hongmei1，LI Peizhen1，PENG Gongsheng2
(1. State Key Laboratory of Disaster Reduction in Civil Engineering，Tongji University，Shanghai 200092，China； 2. CCCC Third Harbor Consultants Co.，Ltd.，Shanghai 200032，China)
Abstract：3D fully nonlinear analysis of seismic response of free field in liquefiable site is carried out using the general finite difference program FLAC3D. Compared with the equivalent-linear method，the permanent and irreversible displacements can be modeled automatically in the fully nonlinear method. A proper plastic formulation is used in the soil nonlinear constitutive relation，whereby plastic strain increments are related to stresses. Combined with the pore water pressure model，soil liquefaction under the seismic excitation can be modeled. Soil nonlinearity，pore water pressure build-up process and boundary condition of the model are taken into account in the calculation model. A comparison between the results from the finite difference analysis and those from the shaking table tests is made to validate the effectiveness of the computational model. Numerical results demonstrate that the liquefied soil can filter and isolate vibration. The phenomena of transient minus pore pressure occurr in the test. Pore water pressure does not always dissipate in short time immediately after the excitations，but it may keep on increasing.
吕西林，任红梅，李培振，彭功生. 液化场地自由场体系的数值分析及振动台试验验证[J]. 岩石力学与工程学报, 2009, 28(S2): 4046-4053.
LU Xilin1，REN Hongmei1，LI Peizhen1，PENG Gongsheng2. NUMERICAL ANALYSIS OF FREE FIELD SYSTEM IN LIQUEFIABLE SITE AND VALIDATION OF SHAKING TABLE TESTS. , 2009, 28(S2): 4046-4053.
