太浦闸洪水风险图编制中溃闸洪水计算分析

Flood Propagation Simulation and Analysis due to Taipu Gate Breach in Flood Risk Mapping

考虑到同步模拟太浦闸溃决和洪水演进的困难以及洪水风险信息管理系统可视化和数据调用的效率,对太浦闸溃决处的洪水演变过程由水量平衡原理进行概化模型计算,然后通过一维水动力模型计算得太浦闸溃闸后太浦河堤防3处易溃堤处同时溃决的流量过程作为二维水动力模型的边界条件来模拟洪水在泛洪区的演进.研究结果表明:太湖与太浦河河道之间的概化模型和河道内、泛洪区分别采用一维、二维水动力耦合模型是洪水风险图编制中的一种简捷有效实用的处理洪水计算的分析方法.

Considering the efficiency and visualization of flood risk information management system and the difficulty in coupling gate breaking process and flood propagation,the flood propagation process at Taipu gate due to breaking can be simply computed based on water volume balance;and a coupled one-dimensional and two-dimensional hydrodynamic model is established to simulate flood propagation in the river channel and flooded area respectively,with one dimensional hydrodynamic model used in Taipu River channel to provide breach flow discharge at three possible embankment breach locations when Taipu Gate in failure as the boundary conditions for the two dimensional hydrodynamic model.The simulation results show that the established model,a simple model to deal with Taihu and river channel at gate breach and a coupled one-two-dimensional model for river channel and flooded area respectively,is valid,efficient and practical for flood risk mapping of Taipu Gate.