基于深基坑施工的概率有限元基准模型参数修正  

Parameter correction of probabilistic finite element benchmark model based on deep foundation pit construction

作　　者：宫亚峰[1] 刘佰鑫 杨建星 何锋[1] 孙亮 田立华[1] GONG Ya-feng;LIU Bai-xin;YANG Jian-xing;HE Feng;SUN Liang;TIAN Li-hua(Transportation College of Jilin University,Changchun 130022,China;China Railway Tunnel Group Road&Bridge Engineering Co.,Ltd.,Tianjin 300308,China)

机构地区：[1]吉林大学交通学院,长春130022 [2]中铁隧道局集团路桥工程有限公司,天津300308

出　　处：《吉林大学学报(工学版)》2024年第12期3534-3544,共11页Journal of Jilin University:Engineering and Technology Edition

基　　金：国家重点研发计划项目(2021YFB2600604,2021YFB2600600);吉林省交通运输科技厅项目(2021-1-1);吉林省交通运输科技厅项目(2024-1-10);黑龙江交通运输厅重点项目(2022-1,2022-2);吉林省科技发展计划项目(20230402048GH);吉林省住房和城乡建设厅“2023年度省级建设科学技术计划项目”(2023-1-1)。

摘　　要：针对深基坑在不同施工阶段支护结构的材料参数、连接刚度及边界条件等均随着施工进度的变化而发生改变,导致采用传统确定性的有限元建模参数方法效率低、速度慢、难收敛的问题,提出了利用概率有限元进行参数修正的基准模型概念,即建立了表征地铁深基坑在不同施工阶段物理参数变化规律的有限元模型。首先,针对深基坑不同施工阶段存在“深度效应”最大水平位移的区域,采用高斯混合模型将围护墙最大水平位移分为不同的簇,并提取均值和方差。然后,建立ANSYS有限元深基坑模型,对深基坑的内支撑和围护墙参数进行有限元修正。最后,在随机有限元修正过程中,利用Kriging预测模型代替解析有限元得到聚类分析的深基坑有限元模型的概率基线。结果表明:基准模型进行参数修正后计算速率和精度得到明显提高,可以为后续数值模拟提供理论基础。In order to account for the variations in construction progress,the material parameters,connection stiffness,and boundary conditions of the deep foundation pit are modified.This results in the utilization of traditional deterministic finite element modeling parameter method being inefficient,slow,and difficult to converge.The following problem is proposed to address this issue:The probabilistic finite element parameter correction of the baseline model concept involves the establishment of a characterization of the subway deep foundation pit in the different stages of the construction of physical parameters.In essence,a finite element model is established to characterize the changing law of physical parameters in different construction stages of subway deep foundation pit.Initially,the Gaussian mixture model is employed to partition the maximum horizontal displacement of the enclosure wall into multiple clusters,thereby extracting the mean value and variance.Subsequently,the ANSYS finite element deep foundation pit model is configured,and finite element corrections are implemented on the parameters of internal support and enclosure wall of the deep foundation pit.Finally,the probabilistic baseline of the deep foundation pit finite element model for cluster analysis is obtained by using the Kriging prediction model instead of the analytical finite element.The results show that the computational rate and accuracy of the baseline model are significantly improved after the parameter correction,which can provide a theoretical basis for the subsequent numerical simulation.

关 键 词：岩土工程 深基坑 有限元 围护墙 水平位移 参数修正 

分 类 号：TV551.4[水利工程—水利水电工程]