Pastor-Zienkiewicz砂土模型静力参数变形敏感性分析

摘要 基于广义塑性理论，针对Pastor-Zienkiewicz(P-Z)砂土模型静力参数，划分为3个方面8个参数，分别分析了各参数变化时对竖向位移的敏感性.研究表明:模型各参数在-40%~40%变化时，弹性模量E的敏感性最大，竖向位移变化率可达66.05%，其次为内摩擦角φ和泊松比μ，竖向位移变化率在±10%以内.而与塑性模量相关的参数，竖向位移变化率均低于±1%，当缺少实测数据时，可根据土工实验资料取值.研究结论可为P-Z砂土模型在地基变形计算时参数的选取提供依据.
Abstract：Based on the theory of generalized plasticity， for static Pastor-Zienkiewicz(P-Z) model parameters， it can be divided into eight parameters from three aspects. The sensitivity analysis of vertical displacement varying with each parameter was performed. The results showed that elastic modulus E exhibits the largest sensitivity， and the corresponding maximum rate of vertical displacement is 66.05%， when the every parameter is changed between -40%~40%. Followed by the angle of internal friction φ and Poisson’s ratio μ， the rate of vertical displacement was within ±10%. But for the parameters about plastic modulus， the rate of vertical displacement was less than ±1%. When lack of measured data， the values of plastic parameters can come from a great amount of geological data. The conclusions can provide important basis for the selection of P-Z sandy model parameters in the deformation calculation of sub grade.