Experimental Study And Seismic Performance Analysis Of The C-shape Curved Bridge

With the development of China’s urbanization process and the implementation ofthe western development plan, bridge construction has made considerable progress.The curved bridge structure with smooth lines and vivid artistic conception can easilyadapt to the route and terrain requirements, and widely used in practical engineering.The curved bridge configuration is unique, there is bend torsion coupling, internalforce and deformation complex; its structural dynamic characteristics and seismicresponse is different from the conventional bridge, has a greater damage in theprevious earthquake damage. Discussion on the dynamic characteristics anddistribution of internal force and deformation of curved bridge structure, study on itsseismic performance and the catastrophe mechanism and to promote the healthydevelopment of the curved bridge are the urgent problem to be solved at present. Basedon a C-shape curved bridge solid model of seismic simulation shaking table test andfinite element simulation analysis, a further study of this type structure studied in thispaper.(1) For the study of the curved bridge structure dynamic response under theseismic action of space To study the space dynamic response of the curved bridgestructure under earthquake action, discusses the failure mode of the structure and allprevious earthquake curve catastrophe mechanism failure mode and disastermechanism of the curved bridge in all previous earthquake are discussed. Combiningthe theory study and the earthquake simulation shaking table test research of thecurved bridge at home and abroad, current problems of the curve bridge structure seismic is analyzed, new research direction is puts forward.(2) In view of the effects of local site conditions on the seismic response of thebridge structure, the common method of structural vibration analysis under multi-pointexcitation is discussed. Based on the multi-point excitation analysis theory of thestructure, discussed the site effect to curve the influence law of dynamic response ofbridge structure the influence law of the site effect to dynamic response of bridgestructure is discussed. Multi-point excitation analysis model of the curved continuousbeam bridge is established by using large-scale finite element software. Through theanalysis shows that, multi-point excitation has amplification effect on the response ofthe structure. Reasonable analysis model should be established in structure analysis,the correct simulation and input method of the actual ground motion should beemphasized, so as to get a real seismic response, and provide a scientific basis forcurved bridge structure seismic.(3) A two-span reinforced concrete C-shape curved continuous beam bridgemodel is designed and produced; External device connected to the vibration table(seismic wave conversion device) is designed and produced, single vibration table withmultipoint excitation is achieved; Seismic simulation shaking table test is conducted,model test and observation under each condition is completed. Experimentalphenomenon to a certain extent reflects the damage crack propagation law and thebasic failure modes of the curved bridge under earthquake; Test data analysis reflectsthe variation of dynamic characteristics of curved bridge and law of dynamic responseof the structure under different earthquake intensity The effect of the height of the pieron failure modes of pier structure and the dynamic response of the overall structure isstudied according to the model test.(4) Design parameters of the curved bridge structure—pier height ratio is putforward, dynamic characteristics and dynamic response of two-span curved bridgestructure with two kinds arrangement form of the pier height is studied by usingdynamic time history method. Analysis shows that, the radial displacement of the piertop is different to the parameter pier height ratio and the high sensitivity of the pier;The internal force coupling mechanism of the girder in the middle pier is complex,difficult to characterize with fewer parameters; The internal forces of pier bottom in the variable high pier is closely related to the layout type of curved bridge piers;Parameters of pier height and pier height ratio have different effects on the dynamicresponse of the curved bridge structure; The dynamic characteristics of the structure issensitive to the arrangement form of pier height.