城市轨道交通有挡肩承轨台优化设计

Optimization Design of Shoulder Rail Bearing Platform in Urban Rail Transit

以DTⅢ2-4型有挡肩弹性分开式扣件配套的整体道床有挡肩承轨台为研究对象,建立有限元分析模型,仿真分析了承轨台尺寸、板下弹性垫板与承轨台混凝土之间的摩擦因数、扣件绝缘缓冲挡肩与承轨台混凝土挡肩之间的摩擦因数及列车轴重对承轨台受力特征的影响规律,并提出了有挡肩承轨台的优化设计方案。结果表明:提高挡肩高度可增大挡肩受力面积,降低承轨台应力水平;承轨台应力随铁垫板下橡胶垫板与承轨台之间的摩擦因数增大而减小,随绝缘缓冲挡肩与承轨台混凝土挡肩之间的摩擦因数增大而增大;随着列车垂向力增大,橡胶垫板和承轨台之间的摩擦力增大,挡肩受到的横向力增幅相对较小。通过提高挡肩高度、采用摩擦因数较大的橡胶垫板、加密有挡肩承轨台铺设密度及增设挡肩构造筋,可提高有挡肩承轨台的横向承载力。

A finite element analysis model was established based on the integral track bed shouldered rail bearing platform with DTⅢ2-4 type retaining shoulder elastic separated fasteners.The influence of the size of the rail bearing platform,the friction coefficient between the elastic pad under the plate and the concrete of the rail bearing platform,the friction coefficient between the insulation buffer shoulder of the fastener and the concrete shoulder of the rail bearing platform,and train axle load on the force characteristics of the rail bearing platform were simulated and analyzed.An optimized design scheme for the rail bearing platform with a retaining shoulder was proposed.The results show that increasing the height of the shoulder can increase the stress area of the shoulder and reduce the stress level of the rail bearing platform.The stress of the rail bearing platform decreases with the increase of the friction coefficient between the rubber pad under the iron pad and the rail bearing platform,and increases with the increase of the friction coefficient between the insulation buffer shoulder and the concrete shoulder of the rail bearing platform.As the vertical force of the train increases,the frictional force between the rubber pad and the rail support platform increases,and the increase in lateral force on the shoulder is relatively small.By increasing the height of the shoulder,using rubber pads with high friction factors,increasing the laying density of the shoulder rail bearing platform,and adding shoulder construction reinforcement,the lateral bearing capacity of the shoulder bearing rail platform can be improved.