基于Morris、Sobol和EFAST的LID设施模型参数全局敏感性分析

Global Sensitivity Analysis of LID Facility Model Parameters Based on Morris,Sobol and EFAST

SWMM低影响开发模块可模拟暴雨情景下LID设施的水文效应,已在我国城市雨洪管理中得到广泛应用。研究以深圳市宝安区新桥河流域为例,选用Morris法、Sobol法和EFAST法分析了SWMM模型输出变量中的蒸发量、雨水下渗、地表径流量和峰值流量对4种LID设施(植被草沟、绿色屋顶、生物滞留池和透水铺装)模型参数的全局敏感性响应,并对比了3种方法的分析结果。研究表明:生物滞留池导水率对蒸发量、雨水下渗和地表径流量影响最显著,生物滞留池植物覆盖率和导水率对峰值流量影响最显著。Morris法、Sobol法和EFAST法计算的参数敏感性有较高的一致性。通过3种方法的对比分析,可有效地提高LID设施参数的敏感性分析的可靠性和准确性,从而为海绵城市优化设计提供技术支撑。

The SWMM low-impact development module can simulate the hydrological effects of LID facilities under rainstorm scenarios,and is widely used in urban stormwater management in China.Taking the Xinqiao River Catchment in Bao’an District,Shenzhen as an example,this paper analyzes the sensitivity of multiple output variables of the SWMM model to the typical LID facilities.The output variables of the model include evaporation,rainwater infiltration,surface runoff and peak flow.LID facilities include vegetative swales,green roofs,bio-retention cells and permeable pavements.It also compares the consistency of the results of the three global sensitivity analysis methods(Morris Method,Sobol Method and EFAST Method).The results show that the conductivity of bio-retention cells has the most significant impact on evaporation,rainwater infiltration and surface runoff,while the vegetation-volume fraction and conductivity of bio-retention cells have the most significant influence on the peak flow.The parameter sensitivities calculated by Morris Method,Sobol Method and EFAST Method are highly consistent.The comparative analysis of the three methods can effectively improve the reliability and accuracy of the sensitivity analysis of LID facility parameters,so as to provide technical support for the optimal design of a sponge city.