基于SWMM模型的城市化区域LID设施优化配置方案研究

低影响开发(LID)设施多组合优于单一设施布设,为科学地选择不同组合设施占比下效益—经济组合的最优方案,以典型城市化区域——常州商务城为例,基于SWMM模型计算典型降雨频率为80%下的3组组合设施的径流总量,根据经济成本的函数计算不同情境下的经济成本,采用线性归一化法和最优化目标函数确定不同设施占比的最优化方案。结果表明在降雨频率为80%时常州商务城的最优占比下的透水铺装—下凹式绿地—生物滞留网格的占比率为46%—49%—46%,此时的径流量控制率为83%。耦合SWMM模型与最优化目标函数能计算出城市化区域不同低影响开发设施占比的经济—效益最优解。研究成果可为低影响开发设施优化配置提供思路,可为当地政府和决策者在低影响开发建设规划中提供技术参考。

SWMM model-based study on optimal allocation of LID facilities in urbanized region

By taking the typical urbanized region———Changhzou Business City as the study case herein，the total runoffs of three LID ( low impact development) composition facilities under the typical rainfall with the frequency of 80% are calculated on the basis of SWMM model，and then the economic costs under various scenarios are calculated according to the functions of the economic costs，while the optimal schemes for the proportions of various LID facilities are determined with the linear normalization method and the objective function as well. The result shows that when the rainfall frequency is 80% ，the proportions of porous pavement—concave greenland—bioretention grid are 46% —49% —46% ，and then the runoff control rate is 83% at this time. Thus，the optimal economic-benefit solutions of various LID facilities in the urbanized region can be calculated by the coupled SWMM model and the optimal objective function. The study result can not only provides an idea for the optimal allocation of LID facilities，but can also give a technical reference to the local government and the relevant decision-maker during the construction planning of the low impact development concerned.