城市湖泊暴雨过程中蓄洪能力研究

Flood storage capacity of urban lake during rainstorm

结合雨水管网箱涵溢流公式,建立二维浅水方程洪水演进模型,模拟城市浅水湖泊在暴雨条件下城市湖泊蓄洪排洪效果。通过深圳荔枝湖两场实测暴雨验证,计算结果和实测资料吻合较好。并计算设计暴雨强度50mm/h情况下,有56961.5m3水体,即45%的降雨径流通过箱涵进入湖内,这大大削减排水管网中洪峰负荷,使街道暴雨径流尽快排出,将暴雨灾害减小到最小。

In this paper,a flood routing model based on two-dimensional shallow water equation and the overflow formula of storm sewer system is developed to simulate the flood storage capacity of urban shallow lake during rainstorm.The modeling results are in a good agreement with two sets of rainstorm field data of Lichee lake in Shenzhen,China.Application to a test case of design rainstorm shows that under the city storm intensity of 50mm /h,about 56961.5m^3 storm water or 45% of the total runoff can be drained into Lichee Lake,which greatly reduces the flooding rate of the storm sewer system.