Study On The Similarity Laws In Structural Model Testing Accounting For Nonlinear Performance Of Structures

In order to obtain all the mechanical responses for the prototype structure accurately using a structural model testing,a structure undergoing into nonlinear behavior needs to be considered in the model design and manufacture.Since the model similarity laws based on dimensional analysis is no longer applicable when considering nonlinearity,and structural model test often focus on the nonlinear responses of structures and components,this study carried out the research on the model test similarity laws accounting for nonlinear behaviors.The main work contents are as follows:1.Considering the effect of material nonlinearity for model testing,for the flexural members of partial prestressed concrete members,a coordinative similarity law considering the similarity of bearing capacity,deflection and prestress states was proposed.The model members are designed according to the traditional bearing capacity similarity and coordinative similarity laws,respectively,and the finite element simulation analysis of the flexural test of the simply supported beam verifies that the coordinative similarity model is more accurate than the bearing capacity similar model in the simulation of the prototype structure,especially for the simulation of deflection.2.Extend the coordination similarity law to flexural members of reinforced concrete members,and propose the coordinative similarity law which is applicable for flexural testing of reinforced concrete members.Choose reinforced concrete beam as the research object,the flexural model of simply supported beams are designed according to the similarity of reinforcement ratio,bearing capacity and deflection responses,respectively.The finite element simulation shows that,compared with the other two methods,the model design method based on deflection similarity has the highest accuracy of similarity.3.In the quasi-static test and shaking table test,the horizontal inertia effect hypothesis in the similarity law is different.The coordinative similarity law for axial compression and bending member model considering P-? effect was proposed.Take an “I” section steel columns,the model components are designed according to the laws without gravity consideration,with gravity and coordinative similarity laws.The results of the numerical simulation analysis of the pseudo-static test and the shaking table test verified that the proposed coordinative similarity laws give out more accurate results for the prototype structure,especially for the simulation of the top nodal deformation of the prototype structure.