跨河斜交桥梁对山区河流行洪影响试验研究

Research and test on effect of cross-river oblique bridge on flood risk of mountainous river

为探究斜交跨河桥梁对山区河流行洪的影响,以四川省某拟建斜交跨河特大桥为例,利用物理模型试验研究,分析了不同工况下桥梁建成前后的水流流态、流速与水位,桥梁建成后的冲刷深度,以及河势稳定性。结果表明:该类错孔布置的柱式墩斜交桥梁对河道水位、流速影响不大,对工程下游由右岸侧向左斜冲水流有一定阻碍作用,使得主流略向右岸侧有一定调整。桥梁所在河段仍属于河势稳定河段,拟建桥梁对河流行洪影响较小。

In order to study the effect of cross-river oblique bridge on flood risk of river course in mountainous area,we took a proposed bridge across a river at an oblique intersection in Sichuan Province as an example.We analyzed the water flow pattern,flow velocity,water level,erosion depth before and after the completion of the bridge under different working conditions,and the stability of river regime by using a physical modeling experimental study.The results showed that this type of diagonal bridge with a staggered arrangement of piers had little impact on the river water level and flow velocity,but had a certain obstruction effect on the oblique water flow from the right bank to the left downstream of the project,causing the main flow to adjust slightly towards the right bank.The research results indicated that the river section remained stable after the construction of the diagonal bridge,and the impact on river during floods by the proposed bridge project was relatively small.