圩区缓冲式排水模式应用条件的研究

Study on Applicability of Buffering Stormwater Drainage System in Polder Area

针对缓冲式排水模式的管道调蓄容积小、超载运行、淹没出流等不利因素,以上海新江湾城为对象建立了管网与河网的耦合水力模型,研究了缓冲式排水模式安全适用所需的条件。结果表明,对综合径流系数为0.5～0.6的缓冲式排水系统,当河道设计常水位与设计地面标高之差为1.2m时,应使缓冲式排水模式管道系统的安全排距<500m;当设计最高水位与设计常水位之差为0.5～0.6m时,应使圩区的安全水面率≥5%。这一研究成果为缓冲式排水模式的安全性评价与推广提供了参考依据。

Considering the disadvantages of buffering stormwater drainage system （ BSDS）, such as small storage volume, overloading and stream flooding, a coupled hydraulic model of the water and river networks for the New Jiangwan Town in Shanghai was developed, and the conditions required for safe application of BSDS were investigated. The results show that the safe drainage distance of BSDS in catchments with runoff coefficients of 0.5 to 0.6 should be less than 500 m if the difference between ground elevation and mean water level is not more than 1.2 m. When the difference between the maximum safe level and mean water level is in the range of 0.5 to 0.6 m, the safe water area ratio of polder area should be more than 5%. This research provides a basis for safety evaluation and wide application of BSDS.