西南艰险山区铁路桥梁防冲刷设计

Scour Prevention Design of Railway Bridge in Southwest Dangerous Mountainous Area

文章对西南艰险山区铁路顺河(江)、跨河(江)桥梁的冲刷计算和桥位选择等方面的问题进行了总结,为山区铁路桥梁设计如何进行冲刷计算和桥位选择提供了一些经验。山区铁路顺河(江)桥梁墩台一般宜设置在受洪水影响较小、流速较低的河滩或河岸附近,不宜设置在水流速度较大的主流处。山区跨河(江)桥梁的桥位布置一般宜选择在河道顺直、河床稳定、水面较窄、水流平稳、水流流向在高低水位时变化不大的河段;不宜选择在急弯、沙洲、分岔、两河交汇或河床采沙取石严重等处。

A series of crucial issues related to the scour calculation and bridge location selection for the railway bridges that go alongside the river and cross the river in southwestern dangerous mountainous regions are concluded in this paper,which gives valuable experiences for the scour calculation and bridge location selection design for the railway bridges in mountainous regions.According to the research in this paper,the riffle area or the area close to the river bank which will be less influenced by the flood is the recommended location for the piers and abutments of bridges that will go alongside the river.In addition,for the bridges that will cross the river,the straight reach section with stable river bed and flow,narrow main channel,and stable flow direction during the water level variation period is a better location than the river section with sharp curves,sandbank cay towheads,bifurcates,river junctions or quarry pits.