低影响开发措施的建设对城镇排涝模数的影响研究

Impact of Low Impact Development Measures for Urban Drainage Modulus

近年来,极端气候频发对城镇内涝的综合治理带来了新的挑战,需采取多种措施构建多重排涝防线。低影响开发措施可有效削减洪峰流量、延缓峰现时间、减小径流系数。针对低影响开发措施实施后对排涝模数这一排涝工程规划中的关键指标的影响展开研究,以广州市大岗镇为背景,建立了LID措施实施后城镇涝水的产汇流模拟的SWMM模型,通过情景分析得到不同LID设置情景下的排涝模数。结果表明:在78.7%的城镇面积(情景6)上实施LID后分别在遭遇5、10、20、30、50a一遇暴雨情景下其排涝模数为未实施LID时的57%,71%,78%,82%,86%。其结果对实际工程有一定的参考意义。

In recent years,the frequently extreme climate brings new challenge to urban waterlogging control to the extent that various measures should be built to reduce waterlogging.Low Impact Development has been extremely effective in cutting dowm runoff peak flux,slowing runoff peak appearance time and reducing runoff coefficient.Drainage modulus is a key indicators in drainage project plan.The objective of this paper is to research the impact of Low Impact Development measures for urban drainage modulus.Using the Dagang town drainage area in Guangzhou as a case study,the rainfall-runoff models of urban waterlogging which the LID measures had been implemented in the drainage area was built with SWMM model.The results indicate that in 78.7% of the urban area（sixth scenario）after implementing LID measures,under the designed rainstorm standards with return period of 5years,10 years,20years,30 years,50years the drainage modulus respectively decreased to 57%,71%,78%,82%,86%in comparison to the condition that the urban area does not implement LID measures.The result has certain reference significance for practical project.