山区铁路沿河傍山通过,要设置跨越沟谷的桥涵。这种桥涵进口端的上游沟床,往往处于地势陡峻且狭窄的地段,必须根据地形特点和不同要求进行设计。设计跨越小型泥石流沟谷的桥涵时,应考虑到怎样尽量减少泥石流能量的消耗,以保证泥石流具有足够的速度,顺利通过。所以,合理地选用桥涵及其上下游沟槽建筑物的纵、横断面形式,是解决泥石流能 Mountain railway along the river Pangshan, to set the bridges and culverts across the valley. This bridge and culvert upstream of the import gutter, often in steep and narrow terrain, must be based on topographical features and different requirements for design. When designing bridges and culverts crossing a small debris flow gully, consideration should be given to how to minimize the energy consumption of the debris flow to ensure that the debris flow has enough speed to pass smoothly. Therefore, the rational selection of bridges and culverts and the structure of the upper and lower trench longitudinal and cross-sectional forms, is to solve the debris flow