Damage Analysis Of Huilan Interchange In Mianzhu During Wenchuan Earthquake

May 12th,2008, an earthquake with Ms=8 occured in Sichuan province in our hometown, which made a great deal of casualties, and the whole nation is with lament. In this earthquake, the collapse and destroy of curved beam bridge, whose representation is Baihua Bridge and Huilan overpass bridge, attracts wide social attention, this two bridges are also the only damage examples of sharp curve beam bridge in earthquake in our nation. In this text, it would take earthquake damage of ramp bridge of Huilan overpass bridge as an example, by using software SAP2000 and taking non-linearity time interval analytical procedure, then proceed numerical simulation and earthquake damage mechanism analyses of earthquake damage process for the bridge. Main jobs and headway is as following:(1) Introduce expound history and actuality of earthquake damage of curved beam bridge and seismic study. High lightly introduced ramp bridge earthquake damage instance of Huilan overpass bridge, which is especially that the curved scissors destroy characteristic of plastic hinge region on the fixing bridge pier top of the whole bridge is comparatively obvious.(2) Proceed free vibration characteristic analyses of Huilan overpass bridge, and then get that whose fundamental period is 0.42s, second period 0.3s. Its Vibration performance appears as inter-inhibitive entirety vibration of high and low pier sides, and amplitude of the high side is greater than the squat one clearly.(3) Proceeding non-linearity time interval analyses by appropriate motion record in Wenchuan earthquake, which takes non-linearity influencing factors as bearing slippage, bridge pier plastic yielding. It studies earthquake damage mechanism of the overpass bridge based on numerical simulation. And get the conclusion as:a) The lowest pier No.1 with bearing slips, as a result the fixed pier No.2 (the second lowest), whose rigidity is much bigger, would receive high earthquake inertia force. b)The No.2 pier occurs bending yielding, then its tensibility develops, at last the shear failure occurs as its resistance to shearing failures, which appear typical curved scissors failure characteristics, and such characteristics is consistent with earthquake damage survey.