Research In Some Of The Key Issues In Large-span Pre-stressed Concrete Continuous Rigid Frame Bridge

High-pier Long-span Continuous Rigid Frame Bridge is a multi-hyperstatic and spaceforce structure system，having both the advantages of the continuous beam bridge and theadvantage of the T-rigid bridge, also the stress is reasonable, economical cost, driving comfortand so on, is widely used in our country traffic construction. But there are many designproblems have not to be resolved, the construction time is affected by a number of factors,and have very limited measures to adjust the completed structure. So, the accuracyrequirements for the design and construction of the bridge is very high, Prospective should befurther for such type of bridge future problems，Development and reservation more problemsolving methods.According to Luo Xiang Bridge (71m+130m+71m PC continuous rigid frame bridge)as engineering background, use the general finite element software MIDAS/Civil, Establishthe finite element model of whole bridge, to study and analyze the actual structure. In thispaper, the main research work includes:(1) analysis of the use of ordinary concrete andHLWC (high-strength lightweight concrete) on bridge structure internal force, stress, linear,Describes the use of HLWC brought the economic benefits for this type of bridge, effect ofspan for this kind of bridge, And the Important significance for structural seismic andstructural stability.(2) Have analyzed the concrete shrinkage, creep of prestressed loss varieswith time, Find that prestress loss with a steel beam at the same time in different beamsegment is different. The main cause of this phenomenon is the different concrete pouringtime of each beam segment. also the reason has to do with steel beam position and tensionsequence.(3) The important factors that control the tension steel beam stress size is effect ofthe prestress loss, Generally speaking, from the economic perspective, we hope the steel beamtension control stress set higher and better, But through the analysis found that, In the tensilestress is higher, due to steel beam caused by relaxation of prestress loss will be moreserious.(4) This paper studied under different load combination under the largest cantileverstage and buckling stability bridge stage, In the maximum cantilever construction stage, foundthat transverse overturning most prone to bridge, And the stability of bridge after completionalong the bridge direction is the worst; Through the analysis of different wall thickness of pier,the pier wall thickness showed great influence on the stability of the largest cantilever stage.(5)After bridge was deflected, the steel beam tension to prevent the bridge in middle long-termdeflection has certain effect, And analysis of the impact of structural strength by tensiondifferent number of reserved steel beam. At the same time, the structure stability analysisbased on the influence of reinforcement. The basic problem we are concerned with the bridge structure is the structural strength,deformation, stability. The whole process of the long-span continuous rigid frame bridgeconstruction stage, completion stage and strengthening stage simulation, for every possiblesituation is calculated and analyzed. At last we get some conclusions are detailed, Hope thatwe can give the kind of bridge design, construction and reinforcement will provide theoreticaland practical reference value.