基于实测脱空的道岔板力学特性分析

Mechanical Property Analysis of Turnout Slabs Based on Measured Void

为给脱空状态下道岔结构的稳定分析和安全分析提供较为真实的理论数据,给道岔区脱空后是否需要及时修补和改善提供理论参考。现场检测某高铁站道岔板的真实脱空状态,利用有限元软件建立道岔板脱空后有限元理论分析模型,计算分析不同动力系数和脱空高度对道岔板竖向最大变形和疲劳寿命的影响。道岔板脱空高度为5 mm且动力系数为3.0时,5号加载位置处竖向最大变形率超过50%;脱空高度对3号位置(叉心位置)的最大拉应力影响比其他位置明显;当其脱空高度为4~5 mm且动力系数取3.0时,道岔板性能将不满足60年的设计使用要求;动力系数对道岔板的最大拉应力影响较大,对叉心位置最大拉应力影响最明显。

In order to provide more realistic theoretical data for the stability and safety analysis of the turnout structure under the void condition,and provide theoretical reference for timely repair and improvement of the turnout area after void,a real void condition of the turnout slab is tested on site.The real void condition of a turnout in a high speed railway station is examined on site,and a finite element FEM theoretical analysis model is developed with FEM software to analyze the effects of different dynamic coefficients and void heights on the maximum vertical deformation and fatigue life of the turnout.The results show that:The maximum vertical deformation rate of the turnout slab at loading point 5 is more than 50%when the height of void is 5 mm and the dynamic coefficient is 3.0;The maximum tensile stress at loading point 3 is more obvious than the other points;When the void height is 4~5 mm and the dynamic coefficient is 3.0,the performance of the turnout slab will not meet requirement for 60 years of designed service.The maximal tensile stress of the turnout slab is more affected by the dynamic coefficient and the affect on the maximal tensile stress of the fork center is the most obvious.