Seismic Response and Safety Evaluation of Ultra-long-span Rail-cum-Road Suspension Bridge in High Earthquake Area
The seismic performance of the Sunda Strait Bridge under frequent and design earthquakes was analyzed using response spectrum and linear time-history analysis method,and the influence of traveling wave effects,dampers,and flexible central buckles on the seismic performance of the bridge was explored.The results revealed that the basic period of the Sunda Strait Bridge is 19.88 s,with obvious long-term characteristics,and the transverse stiffness is smaller than the vertical stiffness and longitudinal stiffness.The time-history analysis results are not less than 80%of the response spectrum analysis results,meeting the regulatory requirements.At the frequent earthquake level,the maximum combined stresses of concrete and steel structures are-11.7 MPa and-189.1 MPa,respectively,indicating each component still work in the elastic stage.At the design seismic level,the maximum stress at each connection part is less than the design strength except for stress concentration areas,indicating the connection structures have sufficient safety reserves.The parameter analysis results indicate that the seismic response is more unfavorable when the non-uniform excitation time difference is 0.6 s or 0.8 s than that the time difference is 1.0 s.The damper has a significant impact on the maximum stress of the main girder,the longitudinal displacement of the girder end,and the relative displacement between tower and girder.The central buckle has a significant impact on the natural vibration characteristics of the bridge and the longitudinal deformation of the main girder.
万方数据
维普
