【摘要】 由于土层等效线性化方法在强地震动输入下会低估地表峰值加速度且不适用于处理具有较大非线性的软弱土层.本文提出了基于动态骨架曲线的土层直接时域积分方法.该方法在动力方程的数值积分中采用中心差分格式,土体的剪切动力本构关系采用了基于动态骨架曲线的简单函数形式以考虑其非线性,在土层底部引入人工透射边界以考虑能量向基底的辐射,并基于MATLAB平台编制了DYMATLAB计算程序.以唐山响堂三维场地影响观测台阵的强震记录为例对本文方法进行验证.结果表明,本文提出的方法能较好地考虑土体的非线性,是一种合理可行的土层地震反应分析方法.更多还原

【Abstract】 The equivalent linearization method underestimates the calculated peak ground acceleration under the strong seismic motion input and it is not suitable for dealing with soft soil layers with relatively large nonlinearity.To better estimate the non-linear site response,a direct-domain integral method based on dynamic skeleton curve constitutive model was proposed.In this method,central difference integration scheme was used to solve the dynamic numerical integral equation,a soil dynamic constitutive relation in a simple function form based on the dynamic skeleton curve constitutive model was introduced to consider soil nonlinearity,multi-transmitting artificial boundary condition had been conducted at the basement of soil layers to consider the effect of energy transmission through bedrock boundary.DYMATLAB program was compiled on MATLAB platform.In order to verify this method,real strong motion records derived from the Xiangtang three dimensional array in Tangshan for site effects on strong ground motion was used to analysis.The results showed that this method could consider nonlinearity of soil layers well and it could be applied as a reasonable and feasible method for nonlinear site response analysis of soil layers.更多还原