基于响应面法的堆石料弹塑性模型参数反演研究

Inverse Analysis of Rock-fill Model Parameters Based on Response Surface Method

采用拉丁超立方设计选取堆石料参数,并通过有限元计算得到大坝竣工期典型测点沉降,采用响应面法建立二者之间的映射关系,根据工程实测得到的测点沉降结果得到堆石料的模型参数,建立了一种基于响应面法的堆石料参数反演方法。针对紫坪铺面板堆石坝,根据上述方法得到的堆石料参数,进行了汶川地震震害模拟,并与实际震害结果进行了对比分析。计算得到的大坝填筑期典型测点竖向位移发展过程以及地震后大坝永久变形与现场实测结果吻合较好。

The Latin hypercube sampling was used to select the model parameters of rockfill for FEM analysis,the settlements of typical observation points during completion period were computed by FEM,the response surface method was used to establish the mapping relationship between the model parameters and the values of settlement,the model parameters of the rockfill were determined by the inverse analysis based on the values of actual measured settlement,an inverse analysis method based on the response surface method was proposed to determine the generalized plasticity model parameters of rockfill materials. The proposed method was applied to determine the rockfill parameters of Zipingpu CFRD through the monitoring settlements in the construction stage. The seismic response of Zipingpu CFRD during Wenchuan earthquake was simulated by the inverse parameters and the results were compared with the actual seismic damage survey. The results indicated that both the developing process of the vertical displacements of the typical points during the stage of construction period and the permanent deformation of the dam due to the earthquake agreed well with the field measured.