Dynamic Effect Analysis Of Urbanlight Rail Continuous Rigid Frame Bridge Under Seismic Action

Thevigorous developmentof urbanization causedincreasingly crowded of the citytraffic system, alsoreduced the city residents’ quality of life. Straddle type light rail cangreatly ease the traffic pressure, but also to the ups and downs of complex terrain has astrong ability to adapt, effectively solve the contradiction between city traffic and citydevelopment at present. Jialing River in Chongqing light rail for continuous rigid framebridge as the engineering background, using bridge analysis software Midas Civil toestablish the finite element model, had did the following aspects of work:①Expounds the characteristics of earthquake disasters and the large earthquakelive at home and abroad recently. Analysischaracteristics of seismic waveandspatialcorrelation betweenseismic wave and bridge structure. Reserchthedevelopmentprocess of urban monorail transit system as well as the development status at home andabroad.②Constructionthe new concept of dynamic characteristic oflight rail trains throughcontinuous rigid frame bridgeunder the conduction action of seismic medium.From theanalysis of the seismic wave medium vector dynamic evolution characteristics.Considereffect of different medium seismic wave on bridge internal force of the structure,explorethe dynamic transfer rules,Get the response of bridge structure under different seismicwave medium and site conditions.③Analysis the naturalvibration of continuous rigid frame bridge through multipleRitz vector method, calculate the structure of the first ten order natural vibrationfrequency, cycle and vibration model, and analyzes the characteristics of each mode.Definition of light rail train loads, marshalling mode and various operatingconditions,analysis displacement and acceleration response of each control section ofcontinuous rigid frame bridge and track beam under various working conditions and thebridge of the dynamic indicators reflect the actual situation. Displacement amplitude ismainly concentrated in the8to17s, acceleration amplitude are mainly concentrated inthe middle period.④Put forward the space dynamic analysis model of train-track-continuous rigidframe bridge under the action of earthquake. Analyse the power mechanism underseismic action of train through bridge. Adopt more incentives in the form of dynamictime history analysis method, selecting Elcent seismic wave, analysis dynamic andinternal force time history response of continuous rigid frame bridge under the earthquake action and drivingdual load, conclusion mainspan across is a weak part, themaximal displacement of8.2cm, maximum acceleration of2.07m/s2.The largest axialforce is part of the bridge pier, the maximum value is6763.09kN. The maximum axialforce and bending moment of girders in the span of mainspan, is2602.40kN and26982.32kN·m. That’sa weak part of the whole bridge.⑤Do in-depth research oncity light rail through continuous rigid frame bridgeunder the action of the earthquake bridge structure and operation safety of the vehicleitself,to ensure the life and property safety of the passenger. From different pier height,different speed and different seismic intensity in three aspects, analysis response thebuilted model under the action of the earthquake, proposed in the earthquake safe trainoperation suggestion.