Numerical calculation of three-dimensional elastic wave equation of piles staggered grid finite difference using method with variable step lengths
LIU Hua-xuan1, 2, LIU Dong-jia1, LU Zhi-tang3, TAO Jun1, JIANG Jing1
1. School of Resources and Environmental Engineering, Hefei University of Technology, Hefei 230009, China; 2. Anhui Institute of Building Research and Design, Hefei 230001, China; 3. Department of Geotechnical Engineering, Tongji University, Shanghai 200092, China
Abstract：To improve the computational efficiency of low-strain numerical simulation of piles, the variable step staggered grid finite difference method is introduced into the calculation of three-dimensional pile-soil model based on the traditional difference method. By differentiating three-dimensional elastic wave equation and introducing absorbing boundary conditions on the computational model interface, the low-strain numerical simulation of the response of piles is calculated under transient vertical excitating force. The results show that the computational accuracy is guaranteed and the computational process is more flexible and simple because of varied difference grids. The process can also reduce the memory requirements and the computational time. The absorbing boundary which absorbs the incident waves reaching the computational model interface is effective. The proposed method has achieved good effects on fitting low-strain measured curve and numerical simulation of asymmetric defective piles.
刘华瑄, 刘东甲, 卢志堂, 陶俊, 姜静. 桩基三维弹性波动方程变步长交错网格有限差分数值计算[J]. 岩土工程学报, 2014, 36(9): 1754-1760.
LIU Hua-xuan, LIU Dong-jia, LU Zhi-tang, TAO Jun, JIANG Jing. Numerical calculation of three-dimensional elastic wave equation of piles staggered grid finite difference using method with variable step lengths. Chinese J. Geot. Eng., 2014, 36(9): 1754-1760.
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