海河交汇区深大基坑开挖力学效应与参数优化OA

Taking the excavation project of Zhuhai Tunnel as the background,a three-dimensional finite element numerical simulation of the entire excavation process was carried out.Combined with monitoring data of internal forces and deformations of the retaining structure,the mechanical effects of deep and large excavation in coastal deep soft soil areas were investigated.The influence mechanisms of soil reinforcement strength within the excavation,diaphragm wall thickness,diaphragm wall embedment ratio,and their combined effects on excavation deformation were systematically studied,followed by an optimization analysis of construction parameters.The results are as follows:①Increasing the reinforcement strength causes the location of the maximum horizontal displacement of the diaphragm wall to shift slightly downward,and the location of the maximum ground settlement to gradually approach the excavation;② When the toe of the diaphragm wall is located in relatively weak soil layers,increasing the embedment ratio has a certain restraining effect on wall deformation;③The combined effect of reinforcement strength and wall thickness is more effective in restraining excavation deformation than any single factor alone;④The axial force of the first reinforced concrete brace increases with excavation depth at first,then decreases slightly,and finally stabilizes.The research findings can provide a reference and basis for the optimal design of soil reinforcement strength,diaphragm wall thickness,and embedment ratio in foundation pit engineering.