Research On Vibration Characteristics And Seismic Design Method Of Buried Corrugated Steel Bridge And Culvert

China often suffers from earthquakes.Each time,the disaster destroyed many structures and traffic facilities,made lots of people lost their properties and even lives.Buried Corrugated steel plate(CSP)bridges and culverts fully exert the superiority of interaction between soil and structure,it performs well in both bearing and deformation capacity.CSP bridges and culverts are also considered to have good seismic performance.However,few researches on the natural vibration characteristics and seismic performance of CSP bridges and culverts had been done by now.The development in this field is relatively deficiency,and many problems remain unsolved.In this paper,the natural vibration characteristics and seismic design method of buried corrugated steel bridges and culverts are studied.The main work is as follows.(1)Experiments on natural vibration characteristics of buried CSP bridges and culverts.In this paper,two models of CSP arch bridges are used to test.1#bridge is CSP structure and 2#bridge is CSP structure with concrete cladding.The Microwave Interferometric Radar is used as the testing tool.The test states are as follows.1)The states before the model bridge filling construction.2)The states of different backfill heights during the construction.3)The states when the construction is completed,after the natural settlement of backfill and loading states were tested.The variation of natural vibration characteristics of CSP bridges under different filling conditions is studied,and the effects of backfill and concrete cladding on the natural vibration characteristics of the structure are compared and analyzed.(2)Research on finite element numerical simulation analysis method of buried CSP bridges and culverts.Two-dimensional model,three-dimensional model with equivalent flat steel plate and three-dimensional model with CSP are established respectively.The finite element analysis results are compared with the measured results of the structures before backfill construction.The finite element analysis method of the soil around the structure is studied by establish the solid element model and the soil spring model respectively to simulate soil effects.The results of the finite element analysis are compared with those of the frequency measurement at the initial stage of the bridge completion.Finally,the finite element numerical analysis model suitable for the research on natural vibration characteristics and seismic analysis of buried CSP bridge and culvert is determined.(3)Research on seismic design method of buried CSP bridge and culvert.Based on the established finite element numerical analysis model,El-Centro seismic wave,Taft seismic wave and synthetic wave acceleration time history data are selected to carry out dynamic time history analysis of the model bridge.The results are compared with the results of the response displacement method.The dynamic response and seismic performance of this kind of structure under earthquake action are studied,and a reasonable seismic design method is put forward.