The Analysis Of Damage Mechanism And Dynamic Of Deck Arch Bridge Under The Action Of Eatrhquake

People love arch bridge because of its economy and beautiful appearance,according to incomplete statistics, arch bridge accounted for70%in our country. Thesouthwest area of China is an earthquake-prone area, due to the terrain and thegeological condition, arch bridge becomes a major bridge form in this region. Bridge isan important part of transportation lifeline engineering, bridge damages not onlydirectly hinder earthquake relief operations, cause secondary disasters increasing,leadto huge life and property loss indirectly, but also bring difficulty to recovery andreconstruction.Arch bridge is different from girder bridge, has a unique advantage. On the pier ofarch bridge have thrust, so the request of foundation is higher. Arch feet displacementscaused by foundation failure belongs to static function, strong vibration of bridgestructure caused by earthquake belongs to dynamic function, due to the inertia force.This paper analyses how the earthquake energy transfers to a arch bridge structure,causes structure vibration and arch feet displacements; and analyses the destructivemechanism of arch bridge structure when the earthquake happened from the point of"dynamic and static combination ".Analyzing a CFST deck arch Bridge of280m,firstly, analyzing the internal forceunder the action of earthquake or arch feet displacement.The action of arch bridge underdifferent vertical displacement and transverse displacement is different.At last, thisessay analysis the change of internal force of arch bridge under the action both ofearthquake and arch feet displacement.The results of the study show that, the arch feet section is weak section;Verticalseismic effects cannot be neglected;Under the joint action of earthquake and arch feetdisplacements, when the arch feet displacement value reach a certain value, the internalforce of arch ring changed dramatically,and the effect is adverse.