Study On Pesudo-Dynamic Substructure Test Method Based On OpenSees

In the seismic tests for large and complex structures, it is difficult to fully satisfythe similarity conditions of the original structure for the small scale model, so largescale or full scale model is used to conduct simulation experiment. However, themodel test of the whole structure is not economic in the test. Based on the above hard,the problem can be solved by advanced seismic test method of substructure pseudodynamic test. Thus, the whole structure could be divided into two parts which are testsubstructure and numerical structure with this method. Generally speaking, thestrongly nonlinear components or local structure is simulated by test substructure,while the other part is modeled by numerical simulated. On the one hand, the complexrestoring force can be confirmed by the test to more really simulate the earthquakeresponse, on the other hand, it can reduce testing scale and cost.Based on the object-oriented and open source software OpenSees, a substructurepseudo dynamic test program was developed, and was verified with a series of virtualtests. In this thesis, the test substructure is carried out by simulating the boundarycondition and loading ways of the actuator. In addition, OpenSees framework with Tclscript language can be used to exchange the test data between the testing substructureand numerical substructure. Lastly, the substructure pseudo dynamic test method isverified feasibility and validity with specific examples.Numerical integration algorithm is the foundation of pseudo dynamic test method.In this thesis, a few numerical integration algorithm which is used in the substructurepseudo dynamic test method is introduced, and this thesis focuses on PCM-Newmarkalgorithm and alpha OS algorithm, then, compared with the two algorithm onaccuracy, stability, and experiment efficiency and continuity, PCM-Newmarkalgorithm is better one in the substructure pseudo dynamic test method.The basic principle of substructure pseudo dynamic test method is discussed inthis thesis, and the dynamic equation is established in the test method based onpseudo dynamic test, besides, the model of substructure building, substructureboundary conditions simulation, the displacement conversion between actuators andsubstructure and how to choose the numerical integration algorithm and the model ofrestoring force etc in substructure pseudo dynamic test method is also introduced,especially, this thesis discusses on theory of nonlinear time history analysis which includes the nonlinear beam-column elements, structural mass matrix and stiffnessmatrix, damping matrix and nonlinear equation, lastly, high-rise steel frame is carriedout the test. The network communication and the data feedback which are insubstructure pseudo dynamic test method is introduced.This thesis elaborates on process of the substructure pseudo dynamic test methodbased on OpenSees, and the basic modeling of OpenSees based on time historyanalysis and related technologies of substructure pseudo dynamic test which includesstep analysis of parameter modification, modification of model parameters andreal-time output item will be mainly introduced in this thesis. At the same time, thenetwork communication of substructure test related theory is introduced, and dataexchange between experimental substructure and numerical substructure is carried outby OpenSees interface with Tcl script file. Besides, the basic principle ofbuckling-restrained brace is introduced in this thesis.This thesis sets buckling-restrained brace high-rise steel structure as an example,then herringbone brace is carried out substructure test in pseudo dynamic test toverify feasibility and effectiveness of substructure pseudo dynamic test method bydifferent layers’ brace and multiple brace in structure. In addition, the structure withgravity load is carried out pseudo dynamic test, and preliminary testing substructureof bottom column is realized in substructure pseudo dynamic test, in this thesis,without considering the deformation of the angle and axial in the pillars to examinehow boundary conditions influence the substructure pseudo dynamic test. Finally, theerror analysis of test results is performed.