基于弹性地基梁的偏轨箱形梁局部应力分析

The local stress analysis about the bias-rail box girder based on elastic ground

小车轮压作用下,轨道与偏轨箱形梁之间力的传递属于接触非线性问题,接触面间的变形和应力分布存在相互耦合的关系。为了求得接触面间的局部应力解,本论文将偏轨箱形梁对轨道的支承视为弹性地基(主腹板)对轨道的支承。基于弹性地基梁假设,当将主腹板视为Winkler弹性地基时,求得Winkler局部应力解。最后将经验公式解与Winkler公式解进行对比分析论证。研究结果表明:Winkler公式解的影响因素为小车轮压P、主腹板厚度δ0、轨道截面惯性矩I和主腹板高度h0,而经验公式解的影响因素为P、δ0和I;通过在相同情况下对比两种解,得出Winkler公式解比经验公式解相对小些。

Affected by trolley under load, the pressure transferred from rail to box girder is of contact nonlinearity problem. The deformation and stress attribution between the contact surfaces exist coupled relationship. In order to get the solution of local stress, this paper will simplify the rail＇s support from box girder as the support from the main web. On the premises of the simplification, view the main web as the Winkler elastic-ground model and finally get a calculation formula. At last, compare and analyze the results from the emprical formula and Winkler formula. The results show that the affecting factors of the Winkler formula are P, the pressure of trolley, δ0, the thickness of main web, I, the second moment of area and h0, the height of main web, however, the affecting factors of the emprical formula are P, δ0 and I. At the same time, the local stress value from Winkler are relatively smaller than the value from the uniform load by comparing the local stress value in the same work situation.