城市堤防漫决模拟——以哈尔滨市松北区为例

洪水灾害是我国城市中发生较为频繁且破坏性较大的自然灾害之一,阻碍城市可持续发展。针对已有研究中设定堤防一点漫决堤情景模拟方法较为单一的缺点,提出多点堤防漫决堤洪水演进方法。以哈尔滨市松北区为实证研究区,以水动力学方法为基础,以不规则网格为洪水灾害数值模型骨架,以一、二维非恒定流为洪水灾害数值模型控制方程,综合构建堤防多点同时漫决堤情景下洪水演进模型,并对研究区不同洪水频率情景进行模拟。研究结果表明,该方法可以较好地模拟多点破堤情景下,即0.5%频率、1%频率、2%频率的洪水演进及叠加效果,其中当破堤1 h后研究区最大淹没水深可达3 m以上,同时利用GIS空间可视化技术对研究结果进行可视化表达,为防洪规划设计提供决策依据。

Simulation and Empirical Study of Multi-Point Overflow Dike of Urban Embankment Taking Songbei District in Harbin as an Example

Flood disaster is one of the most frequent and destructive natural disasters in Chinese cities.In view of the shortcoming of the scenario simulation method of setting a point overburst in the study,a multi-point embankment flood evolution method was proposed. Based on the hydrodynamic method,with irregular grid as the model skeleton and unsteady flow as the model governing equation,the flood evolution model under the situation of multi-point levee overrunning and bursting at the same time was constructed comprehensively,and the different flood frequency scenarios in the study area were simulated. The results showed that this method could well simulate the flood evolution and superposition results of 0.5%,1% and 2% frequency in the case of multi-point dike breaking,in which the maximum submerged depth of the research area could reach more than 3 m after 1 h of dike breaking. Meanwhile,GIS spatial visualization technology was used to visualize the research results. The research results can provide decision basis for flood control planning and designing.