Sesimic Response Analysis Of Long-span Continuous Beam-Continuous Rigid Frame Bridge In Construction Stage

In the21st century, bridge has been higher and longer-span with the increasingdevelopment of transport and highway construction. Long-span continuous rigidframe bridge has been widely promoted and applied in modern bridge engineeringconstruction due to its unique advantages.Long-span bridges are usually located in the traffic main lines whose damage willbring about enormous political and economic loss. Today, Long-span continuousbeam-continuous rigid frame bridge is novel and has experienced less damage,China’s "Guidelines for Seismic Design of Highway Bridges" just presented seismicdesign principles for bridges with a single span over150m.From an economic point ofview, long-span bridge of cantilevered construction in Northeast China can be dividedinto two years, winter construction expected to suspend. Currently, there are fewseismic stability researches on the long-span continuous rigid frame bridge thatexpected to suspend construction in winter. Therefore, it is necessary to study theseismic performance of each cantilevered construction state of Long-span continuousbeam-continuous rigid frame bridge and understand the changed rules andcharacteristics of the structure with the construction process. So, we can ensure thestability of bridge structure under construction and safety of construction workers,help to improve the seismic design theory of long-span bridges and promote theimprovement and development of seismic design specifications.In this paper, bridge1in the north resort of Changbai-Mountain internationaltourism was taken as an example. The seismic response study of this continuousbeam-continuous rigid frame bridge including each cantilever construction state afterstoppages in winter has been done.Mainly on the basic theory of the bridge seismic analysis and discusses the detailedseismic waves’ selection adjustment and input problems of time-history analysismethod.Using professional finite element analysis program Midas/civil to establish thedynamic calculation model of the background bridge structure and get the dynamiccharacteristics of each construction state, analysis the natural vibration period andmain variation modes of the models. With response spectrum method and nonlineardynamic time-history analysis method analyze and evaluate the seismic dynamicperformance of the background bridge, calculate and compare the peak displacementresponse and peak internal force response of main control section. Finding the mostunfavorable construction state and taking measures to ensure the safety of theconstruction process. The calculation results couldbe referenced for future similar bridges’ seismic design.