Research On Large Scale Structure Seismic Response Analysis System

There are several methods in the structural seismic research. Among all, Shaketable experiment is a direct analysis method, but is limited by the size of shake table;Hybrid test, especially the distributed hybrid test with the substructure technique, takingadvantage of the test facilities in different places, has got a good development in recentyears. But most of the hybrid test method uses static condensation method for thesubstructure and only the interested DOFs are considered, resulting a loss of precision,and cannot be used in structure simulation.Efficient and accurate simulation of seismic response of structures is veryimportant in earthquake engineering, and the computational models are often huge whensimulating large structural systems, which is very difficult for common personalcomputers to complete the simulation. Besides, a complex structure may consist ofseveral substructures with different characteristics. It is very appealing to use thesubstructure technique and simulate different substructures in different software, takingadvantage of the software in each field. It is meaningful to integrate the existing finiteelement software into a whole platform in the seismic analysis.The structural seismic analysis method presented in this paper divides the wholestructure into several substructures, and the interaction between the substructures isconsidered. To fulfill the demand of different substructures for different software, everysubstructure is treated as an independent system, and the standard input/outputinterfaces are provided for each of them to transfer the boundary displacements andforces. At the boundary of different substructures, a ’Coordinator’ which is originallydeveloped for distributed hybrid test is adopted to achieve the equilibrium andcoordination.The substructure system for commercial finite element software ABAQUS andopen source software OpenSees is developed separately in this research, so the mainmodules in the seismic response analysis system consist of the ‘Coordinator’ and twosubstructure analysis systems. A complex model which consists of a big platform andfour towers is built for the verification. The result of the whole model analysis and thatof the seismic response analysis system with linear and nonlinear constitutive shows that the seismic response analysis system is able to get an exact solution for the linearstructure, and for the nonlinear model, the accuracy depends on the time interval. Whenthe time interval is small enough, the result is good.To this end, the system is applied to the soil structure interaction problem, whilethe upper structure is modeled in ABAQUS and the soil is modeled in OpenSees. Theinteraction between them is considered in the analysis system and the result shows theability of the system in handling substructures with nonlinear behavior.