山区跨河桥梁的阻水壅高影响研究

Influence of River-crossing Bridge Backwater in Mountainous Areas

桥梁阻水壅高对河道泄洪存在一定不利影响,山区河段跨河桥梁的壅水特性具有一定的复杂性。采用一维水流数学模型法,研究了山区河段不同桥型方案对河道阻水壅高的影响。结果表明,流速、阻水比与桥梁壅水密切相关,流速较小的情况下,壅水值对阻水比的差异更敏感;阻水比总体不大的情况下,壅水值对流速差异更为敏感。山区河段总体流速较大,桥梁防洪评价阶段需充分考虑河道特点优化桥梁布置方案,减小对河道泄洪的影响。

Bridge backwater is bad to flood-control of rivers. It is complicated that backwater of river-crossing bridge in mountainous areas. In this paper, the influence to water-blocking and backwater in mountainous areas was studied by comparing different bridge type schemes, and one-dimensional mathematical model of water flow was used. The results show that bridge backwater is closely related to water-blocking of bridge and river flow. Under the condition of slow river flow, the bridge backwater is more sensitive to water-blocking, while under the condition of not too high water-blocking, the bridge backwater is more sensitive to river flow. As too fast flow in mountainous areas, at the stage of flood control evaluate, different features of river must be fully taken into account in optimizing the bridge type schemes of river-crossing bridge, in order to decrease its negative influence on flood discharge.