简支梁桥上连续结合式无碴轨道层间连接设计

Interlaminar connection design of continuous combined ballastless track on simply supported bridge

针对32m简支梁桥上连续结合式无碴轨道结构,分别用换算截面法、有限元法及刚性简化计算法计算了列车活载、轨道板与底座板间温差及列车制动作用下的层间剪力,得到了层间剪力分布图,依据该图进行了层间连接件的设计。研究结果表明:在列车荷载作用下,层间剪力自梁端至跨中大致呈线性递减分布;轨道板与底座板间存在10℃温差时,层间剪力主要集中在桥梁两端5m范围内;制动力作用下,结合面上层间剪力沿跨长均匀分布,均等于作用在轨道板之上的扣件纵向分布阻力;当三者共同作用时,轨道板与底座板之间的温差起控制作用,因此,桥梁端部受温差影响较大的5m范围内应加密销钉与连接钢筋设置。

The interlaminar shear force of continuous combined ballastless track on 32 m simply supported bridge was studied under train load, temperature difference between track slab and support slab and braking force with conversion section method, finite element method and rigid simplified method respectively, its distribution diagram was gotten, and the interlaminar connection design was proposed based on the diagram. The result shows that the shear force under train load linear decreases from the bridge end to the middle; the shear force is concentrated in the 5 m region next to the bridge end when there is a 10℃ temperature difference between track slab and support slab; the shear force under braking force evenly distributes along the bridge, which equals to the longitudinal resistance of fastener; when the three factors act together, the shear force is controlled by the temperature difference, so more dowels and connection rebars should be set in the 5 m region, which is heavily influenced by the temperature difference. 1 tab, 8 figs, 12 refs.