Research On The Seismic Performance Of Double Deck Bridge With Portal Pier

Bridge’s seismic research has always been one of the focuses of the bridge designers, in many cases even the control factors of bridge design. With the rapid development of urban construction, urban traffic flow and limited space resources has become a pair of irreconcilable contradiction.Double Deck bridge, to some extent,could alleviate this contradiction. But double bridge seismic research is lagging behind the actual construction.This article reviews the development course of double bridge and present research situation, the current theory of bridge seismic design method are introduced. On this basis, built space model considering interaction of piles and soil with the finite element software Midas Civil,and analyzed the dynamic characteristics of double deck bridge; Then carried on the design of response spectrum according to the existing design specifications, and E1and E2are discussed respectively under the action of earthquake, the force of the pier and the pile body, the strength of pile body according to the ability to protect components to calculate.In order to further study of bridge pier, the stress of the pile after entering elastic-plastic state, set up a bridge pier, elastic-plastic fiber model of pile body, and carried on the dynamic elastoplastic analysis, the piers and pile into the order of the plastic stress characteristics are analyzed and discussed, and some meaningful conclusions were put up for practical design.For excessive tension pile head conditions, this paper puts forward a new type of seismic profile, collisions by choosing appropriate design parameters such as stiffness, can effectively reduce the internal force of bottom structure, decrease the size of cross section design, and can ensure that the relative displacement of the pier beam does not too big and fall beam dangerous.