针对穿越分洪区的高速公路建设问题, 利用分洪区平面二维洪水演进数学模型, 对分洪区内高速公路工程修建前后的分蓄洪过程进行了数值模拟。通过对分洪流量、分洪历时、水位过程、流速过程、堤防近岸流速等分洪要素的计算结果分析, 提出在分洪区内修建高速公路时应着重考虑分洪时公路边坡的稳定性和抗渗性、防排水系统的完善以及高架桥桥孔的布设等, 最大限度地保证公路自身的防洪安全;同时也应从保证防洪建筑物(堤防、安全区)的安全、防洪通道的畅通等角度出发, 进一步优化公路设计, 最大程度地降低工程对防洪设施的不利影响。

To solve the problem of freeway construction in flood retention area, a plane two-dimensional numerical model was employed to simulate the flood propagation process in the flood retention area. By comparing differences of flood discharge, time, water level and velocity from the numerical model without and with the road in the flood retention area, important aspects to flood control which must be considered in the planning of freeway were recommended. From the respect of freeway safety, it was very important to consider fully stability and impermeability of side slope, improvement of drainage system, and arrangement of viaducts. From the respect of flood-control works safety, such as dike, safety zone, and straightness of flood control road, freeway design should be more optimized. So it may furthest reduce the adverse effect to flood control establishment.