Study On Substructure Hybrid Test Utilize The Interface Element Method

The sub-structural hybrid testing method is a research focus at present,as one of the testing method for earthquake resistant building.The basic principle of the method is to build and test the complex part of the structure for its accurate restoring force,while the others are simulated in the computer to get its inertia and damping force.In this way not only the structural dynamic property is taken into account,but also the cost of the specimen as well as the need for the loading device are reduced.The key points of the sub-structural hybrid testing method is the boundary coordination issues between different sub-domains.In this dissertation,based on the interface element method,several problems were studied including the correlation of the subdomains with different numbers of degrees of freedom,the support excitation and the multiple-support excitation.Then,the viscous spring artificial boundary theory and the ground motion input was studied.Finally,the Niu lanjiang bridge model was taken as an example to invest the soil-structure interaction in earthquake response,and the feasibility of the interface element method was verified.The investigation of this work includes:1.To coordinate multiple sub-structures with different boundary conditions,the interface element was proposed and modified to be applicable in the hybrid testing system by introducing the static condensation technique and the BFGS method.Through the simulation of a plate-plate model,the feasibility of the modified method was verified.2.Based on the transfer element theory in solid-shell correlate problem,a transfer function was introduced to the interface element method to correlate the subdomains with different numbers of degrees of freedom.The Shell-beam models was established in ABAQUS and the feasibility of the method was verified.3.Support excitation and multiple-support excitation problem was studied,and the modified interface element method is verified by the shell-beam model.Then a preliminary analysis of the traveling wave effect was conducted.4.The viscous-spring artificial boundary theory was investigated,two-dimensional and three-dimensional soil models with different parameters were established in ABAQUS and the feasibility of the method was verified.5.The Niu Lanjiang bridge model was developed in ABAQUS taking into account the soil-structure interaction.According to the artificial boundary theory,the ground motion input to the boundaries of the soil was determined.