二维溃坝洪水模型在西丽水库中的应用

为分析西丽水库主坝历次除险加固效果及坝体现状,假定一种可能出现的溃坝工况,选取经验公式计算此时的溃坝形式、溃口形态及流量过程,建立MIKE11水动力模型,由断面插值生成二维地形,并采用分段模型法,以溃口流量过程线作为上边界条件,以深圳湾P=0.5%(3.03m)极端高潮位过程线作为下边界条件,搭建二维洪水演进模型,计算得下游洪水淹没历时、水深及淹没范围,分析溃坝对大沙河流域所产生的风险,最后采用水量平衡法对模型结果进行验证。结果表明,所建模型计算结果可靠,能较好反映溃坝洪水运动特性,为西丽水库应急预案提供参考。

Application of Two-dimensional Dam Break Flood Model in Xili Reservoir

To analyze the reinforcement of the main dam and current conditions of the dam body for Xili Reservoir, assuming an occurrence of dam break, empirical formula was chosen to calculate the dam break form, shape and discharge. Hydrodynamic model based MIKE 11 was established, and two-dimensional topograpgy was generated by cross-section interpolation. The piecewise model method was used to establish two-dimensional flood routing model by taking the dam-break flow process as upstream boundary and Shenzhen Bay P=0.5%(3.03 m) extreme climax process as the downstream boundary. The downstream flood submerged duration, range and depth were calculated to analyze the risks of dam-break flood to Dashahe basin. Finally, the water balance method was adopted to verify the model results. It shows that the model calculation results are reliable, and reflect the motion characteristics of dam-break flood, which provides a reference for emergency plan of Xili reservoir.