【摘要】 采用应力型多重势面模型模拟堆石体的本构关系.由于多重势面模型没有明确的屈服面,因此不存在传统意义上的加卸载判据.采用邓肯模型的加卸载准则对多重势面模型的加卸载进行判断,并依据弹塑性理论卸载时塑性刚度矩阵取为0.模型参数选择邓肯E-B模型的参数,利用自行开发的三维有限元法对金钟面板堆石坝进行应力变形分析,并与邓肯E-B模型以及沈珠江双屈服面模型计算结果进行比较.结果表明,多重势面模型计算的竣工期堆石体最大沉降量与实测吻合较好,蓄水期面板应力以压应力为主,与已建工程的实测情况相符,既避免了沈珠江双屈服面模型计算的垂直向位移值偏小的问题,又克服了邓肯E-B模型计算的面板底部顺坡向出现较大拉应力的缺点.更多还原

【Abstract】 The stress-type multi-potential surface model is used to simulate the constitutive relation of rockfill material.Because the multi-potential surface model lacks yield surface to judge loading and unloading,the loading and unloading criteria of Duncan-Chang model are adopted,and the plastic stiffness matrix on unloading can be taken as 0 according to elastic-plastic theory.The parameters of Duncan E-B model are used as the model ones in the paper.The stress-deformation analysis of Jinzhong CFRD with the model is carried out by using the developed 3-D FEM program,which results are compared with those of Duncan E-B model and Shen Zhujiang’s double-yield surface model.The results show that the calculated dam settlement calculated with the multi-potential surface model in construction period is in a good agreement with the measured maximum value,and concrete face slabs in storage period are mostly subject to compressive stress,which are conformed with the measured values of some built CFRD,overcoming the problem of smaller vertical displacement calculated with Shen Zhujiang’s double-yield surface model and the defect of higher tensile stresses along slope direction occurring at the bottom of face slabs calculated with the commonly used Duncan E-B model.更多还原