The Hybrid Testing Method For Large-Scale Structures

With the development of our national economy,large-scale structures are becoming more and more widely used in China.China is an earthquake-prone country,ensuring the safety of large-scale structures under earthquake has important practical value.Large-scale structures tend to have a huge amount of work and complex structural forms,so model tests are necessary to decide their actual response under earthquake.The hybrid testing methods,which overcome the difficulties of the quasistatic testing method and the shaking table testing method,are proved to be economic and efficient.However,their application to large-scale structures still faces many problems.Therefore,to protect the seismic safety of large-scale structures,it is of great theoretical and practical value to study appropriate ways applying hybrid testing methods to large-scale structures.In order to apply the real-time hybrid testing method to large-scale structures,Guo Jin proposed GI-RTHT method.This paper continues the research by this method,the main work are as follows:(1)By comparing the GI-RTHT method with the iterative method,the principle,operation steps,convergence criteria of GI-RTHT method and its numerical calculation in the finite element software are introduced.(2)Taking a mass-spring-damping system as an example,the stability of the GIRTHT method is analyzed.The analysis results show that the stability of the GI-RTHT method depends on the spectral radius ? of the experimental structure.If ?<1,the GIRTHT method can convergence;for the large-scale structures,their ? ? 1,so GI-RTHT method has good stability and convergence for them.(3)The GI-RTHT method is used to test a large-span cable stayed bridge.The experimental results show that the GI-RTHT method has good stability and convergence for large complex structures.(4)A comparative study is conducted on existing hybrid testing methods.Different kinds of testing models are selected and simulated by different hybrid testing method based on a model of a hybrid testing system.The results show that GI-RTHT method can be applied to every kind of large-scale structure;the pseudo-dynamic testing method is only applicable to large-scale structures whose key components are not speed-related;the real-time hybrid testing method is not suitable for large complex structures.