面向内涝防治的地下调蓄池容量设计

针对日趋严峻的城市内涝问题,为了在海绵城市系统建设过程中提高地下调蓄设施的有效性和合理性,总结归纳了一种面向内涝防治的调蓄池布设方法。根据萍乡市西门内涝区现状积水情况及成因,在考虑其他海绵设施调蓄能力的基础上,借助水文水动力学模型(MIKE FLOOD)筛选出需要布设地下调蓄池的易涝区。根据调蓄池容量推理公式法,以水力高差为变量制定初步调蓄方案,通过模型计算易涝区积水情况确定调蓄规模预估范围。根据预估结果和模型试算法比选以脱过系数为控制因子制定的调蓄方案,以最大积水深不超过40 cm和交通影响时间不超过30 min为判断指标最终确定各易涝区的最优调蓄容量。结果表明,通过推理公式和水文水动力学模型相结合的方法可以较为准确、快捷地确定调蓄池容量,结合调蓄规模、选址地点和布设范围计算的池深也在水力高差估算范围内,进一步证明了调蓄池设计容量的合理性和可行性。研究成果可为城市洪涝管理和调蓄设施布局提供决策参考。

Waterlogging control oriented-design of capacity of underground rainwater storage pool

Targeting at the increasingly severe problem of urban waterlogging，a waterlogging control oriented-method for the layout of underground rainwater storage pools is summarized herein，so as to enhance the effectiveness and reasonability of the underground rainwater storage pool during the construction of the sponge city system． In accordance with the current waterlogging situation in the waterlogging area of Ximen District of Pingxiang City and its causation，the areas prone to waterlogging where the underground rainwater storage pools are necessary to be layouted are sorted out by means of the hydrological and hydrodynamic model ( MIKE FLOOD) under the consideration of the regulation and storage capacities of the other sponge facilities． According to the rational formula method for the capacity of the rainwater storage pool，a preliminary regulation and storage scheme is made by taking the hydraulic height difference as the variable，and then the pre-estimated range of the regulation and storage scale is determined through the model calculation made on the waterlogging situation of the area prone to waterlogging． The optimal regulation and storage schemes of all the areas prone to waterlogging are finally determined by taking the maximum water depth below 40cm and the impacted time of traffic less than 30min as the judging indexes through the regulation and storage schemes made by taking the stripping coefficient as the control factor through the comparative selection on both the pre-estimated results and those from the relevant model trial method． The capacity of regulation and storage pool can be more accurately and quickly determined through the method combined with both the relevant rational formula and hydrological and hydrodynamic model，while the pool depth calculated in combination with the regulation and storage scale，the location of the selected site and the layout range is also within the estimated range of the hydraulic height difference． The study result can provide a decision-making reference for urban flood and waterlogging management and the layout of the relevant regulation and storage facilities．