Study On Water-substructure Of Bridge Interaction Under Earthquake Action And Wave Action

The time domain method to calculate the earthquake-induced and wave-induced hydrodynamic pressure on the substructure of the cross-sea and cross-river bridges are studied systematically by theoretical analysis and numerical research in this dissertation.The concrete works in this dissertation are as follows.(1)Based on the infinite domain model of the water in horizontal direction,the exact artificial boundary condition for incompressible water and the high-accuracy artificial boundary condition in time for compressible water are proposed,and the full finite element analysis model and method is established for simulating the dynamic interaction between the cylinder with arbitrary cross section or complex structure with water.(2)The substructure methods including one-dimensional beam element model and three-dimensional solid element model for analyzing the hydrodynamic pressure on flexible circular cylinders and rectangular cylinders with uniform section surrounding by compressible or incompressible water are presented,which is implemented into commercial software ABAQUS by user element subroutine.(3)Based on the hypothesis that the uniform cylinders,the time-domain simplified formulas considering and neglecting water compressibility are developed to calculate the hydrodynamic pressure caused by inner water and outer water of the hollow circular,elliptical,and rectangular,cylinders respectively.(4)Based on analytical method and numerical method,the influence of free surface wave,water compressibility and bottom flexible reflection boundary on hydrodynamic pressure on rigid circular cylinders with uniform section is analyzed,and the influence of water on dynamic characteristics of the flexible circular cylinders with uniform section is analyzed.(5)Based on one-dimensional beam element model and three-dimensional solid element model,dynamic responses of the circular and rectangular piers with uniform section under combined earthquake and wave action are studied,and the soil-pier-water dynamic interaction under combined earthquake and wave action is also investigated.