The Analysis Of Longitudinal Forces Of Three Dimensional Finite For Ladder Sleeper On Bridge In Urban Rail

At present, we are focusing on large-scale construction of urban rail transit, while laddersleeper has superior ability to disperse dynamic load and is able to reduce the vibrationobviously, so it attracts more and more attention from many cities. There are many researchesabout ladder sleeper at home and abroad, but the former researches focus on vibrationreduction about it. However, the research of transfer of longitudinal forces of the rail equippedwith ladder on bridge remains in its infancy. others, ladder sleeper has good integrity, theplane mechanics calculation model in this aspect cannot reflect real situations aboveeffectively. So a three-dimensional finite element mechanical model for calculating theadditional longitudinal transmission of the rail equipped with ladder on bridge has animportant significance.With a three-dimensional finite element space mechanical model, taking a5-span30msimple-deck double track box girder in one city as an example, referring to the existingliterature, selecting reasonable parameters and basing on finite element theory, this thesis hascompared the results of taking convex retaining platform and elastic support with withouttaking, and studied the longitudinal forces and longitudinal displacement of the differentoperation condition,such as,contractility, flexural force, brake resistance, force of continuouswelded rail equipped ladder sleeper on urban rail, analyzed of similarities and differences andsummarized its change rule, and lastly fined convex retaining platform and elastic supportshouldn’t be neglected when calculating the additional longitudinal transmission of the railequipped with ladder on bridge has an important significance. Due to the research on laddersleeper is less at home and abroad, therefore, this paper analysis the rule of longitudinal forcewith the different structure parameters.The major work of parameters study is the influence of the longitudinal force, which isdone corresponding to the different operation condition, the value of the stiffness of convexretaining platform’s cushion, stiffness of pier. The analysis showed that temperature variationof beam is largely affect on contractility, convex retaining platform is largely affect onflexural force, which is not ignored in the design of urban rail transit, stiffness of pier is littleaffect on contractility and flexural force,but it is largely affect on brake resistance, the valueof continuous welded rail equipped ladder sleeper on urban rail eases than value increased bya quadratic in traditional mode.