地铁扣件轨下调高对T型螺栓的影响分析

Effect of Height Adjustment Under Rail of Metro Fasteners on T-Bolt

针对一地铁路段的螺栓弹条扣件系统调高后的适应性问题,基于非线性有限元理论建立Ⅱ型弹条扣件系统关键零部件的三维实体有限元模型,计算不同地段下扣件系统的动态荷载,分析不同轨下调高量下T型螺栓的受力规律。研究结果表明:在动态荷载作用下,T型螺栓主要受螺母拧紧力矩和轨下调高量的影响;随着轨下调高量的增加,T型螺栓根部最大等效应力显著增加;应尽量避免T型螺栓出现塑性变形,且须保证一定安全余量。在正常螺母拧紧力矩条件下,建议轨下最大调高量在半径小于600 m的曲线地段不超过15 mm,一般地段不超过30 mm。

In view of the adaptability of the elastic bar fastener system with bolt in a local railway section after elevation adjustment,a three-dimensional solid finite element model of key components ofⅡ-type elastic bar fastener system was established based on nonlinear finite element theory.The dynamic load of fastener system in different sections was calculated,and the stress law of T-bolt with different height adjustment under rail was analyzed.The results show that under the dynamic load,the T-bolt is mainly affected by the tightening torque of the nut and height adjustment under rail.With the increase of height adjustment under rail,the maximum equivalent stress at the root of T-bolt increases significantly.Plastic deformation of T-bolt should be avoided as far as possible,and a certain safety margin must be ensured.Under the condition of normal nut tightening torque,it is suggested that the maximum height adjustment under rail should not exceed 15 mm in curve section with radius less than 600 m,which should be less than 30 mm in general section.