软黏土在循环荷载作用下动力本构模型的研究

针对软黏土在循环荷载作用下的变形特性，即几乎不存在纯弹性变形阶段及应变趋于零时仍存在能量耗散，结合软土地铁车站振动台模型试验中对饱和软黏土进行的动三轴试验，利用边界面模型理论建立了软黏土的黏弹塑性动力本构模型。并进一步利用该模型对自由场振动台试验进行数值模拟计算，计算与试验的结果基本吻合。该本构模型可用于循环荷载作用下软黏土的动力响应分析。

Study on dynamic constitutive model of soft soils under cyclic load

A total stress-based bounding surface visco-elastoplastic model for soft clays is developed to accommodate multiaxial stress reversals. The model is constructed based on the dynamic triaxial tests of the model soil for the metro station structure shaking table model test, taking into account that the clays yield under very low stress level and present energy dissipation even the strain tending to zero under cyclic loading. The numerical simulation of the free field model test is performed based on the visco-elastoplastic model; and it is shown that the acceleration history of model soil is consistent with the results of the model test.