Numerical Simulation Method And Application To Seismic Analysis Of Soil-Structure Interaction System

Frequent earthquake disasters have brought a great loss of life and property to people, and they also increase the urgency of seismic analysis and research. With the rapid growth of the acceleration of urbanization and development of traffic facilities, large number of super-tall builds, bridges, and tunnels are constructed. These new projects usually require large-scale, unique shape and multi-functions, which imposes a great challenge on the seismic research of projects. Soil-structure interaction is a complex nonlinear problem and needs huge calculation consume, which is often included in engineering structure. Numerical simulation method is widely used in seismic research nowadays, and large-scale numerical simulation is feasible with the application of parallel computing. Based on the engineering practice, this paper studies the numerical simulation method of the soil-structure interaction system. The main contents include:Numerical modeling method of the soil-structure interaction system is studied. The soil-structure interaction model is established by the bucket sorting search method based on segment and bi-direction contact manner. The multi-layers modeling method of soil is researched, which makes the soil model more consistent to geological survey data. The maximum element size of soil is controlled by the propagation characteristics of seismic wave in soil. The semi-infinite foundation in the seismic analysis of soil-structures is simulated by artificial visco-elastic boundary, and several numerical tests are performed to verify the boundary.High performance computing method of soil-structure interaction system is studied. The soil-structure interaction system, which includes larger number of geometric nonlinear, material nonlinear, and contact nonlinear problems, requires huge computing consume. The explicit integration algorithm, with the advantages of higher computational efficiency and suitable for parallel computing, are used to solved this model. With high-performance computer Dawning 5000A of the Shanghai Supercomputer Center, a soil-structure interaction balanced algorithm for domain decomposition is designed and implemented according to the characteristics of soil-structure interaction model. Three engineering application examples of soil-building system, soil-bridge system and soil-tunnel system confirmed that the partition method has higher speedup and better parallel efficiency.Numerical simulation for soil-building interaction system is carried out in the application of Shanghai Center Tower in Shanghai. A 3D refined finite element of soil-pile raft foundation-main structure-curtain wall structure system is established according to engineering drawings. Four seismic accelerograms are selected as inputs in the seismic analysis. The seismic responses of the main structure and curtain wall structure are analyzed under different seismic intensity. The final results provide a reference for the seismic design of Shanghai Center Tower.Numerical simulation for soil-bridge interaction system is carried out in the application of Minpu II Bridge in Shanghai. A 3D refined finite element of soil-bridge system is established according to engineering drawings. A bedrock seismic accelerogram with 10% probability of exceedance in 50 years is selected as inputs in the seismic analysis. The seismic responses of the main tower and main truss are analyzed under uniform Excitations and non-uniform Excitations. The final results provide a reference for the seismic design of Minpu II Bridge.Numerical simulation for soil-tunnel interaction system is carried out in the application of Shanghai Chongming cross Yangtze tunnel in Shanghai. A 3D refined finite element of soil-tunnel system is established according to engineering drawings. A bedrock seismic accelerograms with 3% and 10% probability of exceedance in 50 years is selected as inputs in the seismic analysis. The seismic responses of lining and connectional passage are analyzed under uniform Excitations and non-uniform Excitations. The final results provide a reference for the seismic design of Shanghai Chongming cross Yangtze tunnel.