轮轨高频瞬态冲击下钢轨螺栓孔棱边受力分析

Edge Force Analysis of Rail Bolt Hole Under Wheel-Rail High Frequency Transient Impact

为研究螺栓孔在轮轨接触应力场作用下的棱边应力分布规律及受力特性,建立带有螺栓孔的三维轮轨瞬态滚动接触有限元模型,研究列车牵引、制动及钢轨擦伤所致高频激励下车轮动载对螺栓孔棱边应力峰值及分布规律的影响。结果表明:擦伤位置是影响螺栓孔棱边受力特性及应力分布规律的关键因素;轨面擦伤可激发高频附加动力冲击作用,螺栓孔斜向棱边Mises应力峰值随运营速度的提升而显著增加,轨面擦伤使斜向棱边方向螺栓孔应力集中效应显著加剧;列车牵引状态加剧了螺栓孔45°、225°方向棱边应力集中效应,而制动状态加剧了螺栓孔135°和315°方向棱边应力集中效应。

In order to study the edge stress distribution laws and force characteristics of bolt holes under wheel-rail contact stress field,a three-dimensional wheel-rail transient rolling contact finite element model with bolt holes was established to study the influence of wheel dynamic load under high frequency excitation caused by train traction,braking effect and rail scratch on the peak value and distribution laws of edge stress of bolt holes.The results show that the location of scratch is the key factor affecting the stress characteristics and stress distribution of bolt hole edges.Rail surface scratch can stimulate high frequency additional dynamic impact.Mises stress peak value of oblique edge of bolt hole increases significantly with the increase of operation speed,which can significantly aggravate the stress concentration effect of oblique edge of bolt hole.Under the action of traction,the effect of stress concentration on the edges of bolt holes at 45° and 225° directions is strengthened,and the stress on the edges of bolt holes at 135° and 315°directions is increased under braking.