Static And Dynamic Analysis And Temperature Effect Research Of Cross-seat Type Continuous Steel-concrete Composite Track Beam Bridge

This thesis first introduces the development process of straddle-type track girder bridges,summarizes the structural forms and mechanical characteristics of such bridges,and takes the development and changes of track girder bridges abroad in recent decades as an example to introduce such bridge types.Aiming at the 40+65+40m continuous steel-concrete composite track girder bridge of straddle-type monorail project,the engineering background and design scheme are introduced in detail,and the finite element model of the whole bridge based on beam element is established by MIDAS / Civil software.The structural stress and deformation under the action combination of dead load,wind load,vehicle load and temperature are calculated respectively and checked by the allowable stress method.According to relevant codes,the pile-soil model for calculating the bridge is established and its natural vibration characteristics are calculated,and the influence of pile-soil action on the natural vibration characteristics of the structure is compared.Response spectrum method and time-history method were used to calculate and analyze the seismic response of the bridge,and the differences between the two seismic calculation methods were compared.The finite element software ANSYS is used to establish the detailed finite element model of the whole bridge with solid elements and plate and shell elements,to calculate the detailed stress distribution of the bridge structure under the combination of the three unfavorable wheel positions of the vehicle load and other loads and to check the stress.Finally,the possible sunshine temperature,seasonal temperature and temperature gradient of different materials are compared and analyzed,and the deformation of the structure under adverse temperature and the reaction force of the support are calculated.