Seismic Response Analysis Of Monorail Steel Track Beam Of Strddle Type Light Rail Transit

This paper takes the simply supported steel track beam with span 40.5m of straddle type light rail transit of Chongqing city as the research object, the seismic of which is analyzed, the main content and conclusions were as follows:1. The finite element software'MIDAS/Civil'was used to establish the calculating steel track beam model. The free vibration characters of the natural frequency and vibration modes of this calculating model were obtained. The results show that the beam analyzed has sufficient rigidity, and the vertical stiffness was slightly smaller that the lateral stiffness; the parallel connecting was influential to the lateral stiffness, but on little effect on the vertical and torsional stiffness.2. The stress and displacement of the track steel beam under various loading combination was analyzed. The maximum stress and displacement response was got, and it was found that the steel track beam meets the strength and stiffness requirements; the maximum stress of the steel beam occurs in the box girder of the roof and the maximum shear stress occurs near the web of the bearings.3. Using the subspace iteration method and the seismic standard response spectrum of 08 railway bridges aseismic design code, the seismic responses of the steel track beam was analyzed. The maximum stress and displacement of the steel beam with the seismic action was calculated. The results show that the steel track beam meet the design requirements, and the parallel connecting was the maximum stress in the whole structure.4. Taking the seismic wave as the input, the time-history analysis was done based one the Newmark method and the maximum stress and displacement response were computed. Compared with response spectrum method, the maximum tress and displacement response had the same occurrence regularity, but the value was slightly smaller.