基于监测和模拟的简单式绿色屋顶径流系数取值范围分析  

Monitoring and simulation-based analysis on runoff coefficient value-taking range of extensive green roof

作　　者：张郁媛 宫永伟[1] 张贤巍 吕雪莉 陈博 ZHANG Yuyuan;GONG Yongwei;ZHANG Xianwei;LYU Xueli;CHEN Bo(Key Laboratory of Urban Stormwater System and Water Environment(Ministry of Education),Beijing University of Civil Engineering and Architecture,Beijing 100044,China;Beijing Tongzhou District Water Affairs Bureau,Beijing 101100,China)

机构地区：[1]北京建筑大学城市雨水系统与水环境教育部重点实验室,北京100044 [2]北京市通州区水务局,北京101100

出　　处：《水利水电技术（中英文）》2022年第1期14-25,共12页Water Resources and Hydropower Engineering

基　　金：国家自然科学基金项目(51879004);北京建筑大学市属高校基本科研业务费专项资金资助项目(X20160)。

摘　　要：简单式绿色屋顶具有多种环境和社会效益,对雨水径流有一定的调控效果。针对当前相关标准规范未对绿色屋顶径流系数取值范围做详细分类和计算说明的问题,提出基于监测和模拟的简单式绿色屋顶径流系数取值范围分析方法。为提高绿色屋顶径流系数取值的准确性,基于降雨和径流监测数据分析了简单式绿色屋顶试验装置场次降雨条件下的产流情况和径流系数的取值范围,利用SWMM模型对简单式绿色屋顶年均雨量径流系数进行了模拟计算。结果表明:简单式绿色屋顶对小雨和中雨的径流控制效果较好,对暴雨和大暴雨的滞留效果明显降低。随着降雨强度等级增加,简单式绿色屋顶的产流场次占比逐渐增加,流量径流系数及雨量径流系数逐渐增大。峰流量径流系数的取值范围为0.001~0.382,场次雨量径流系数的取值范围为0.002~0.663。基质层厚度、基质层种类和排水层种类是影响简单式绿色屋顶场次雨量径流系数取值的主要因素。不同类型简单式绿色屋顶的年均雨量径流系数的范围为0.104~0.324,低于相关标准规范和设计导则中的绿色屋顶雨量径流系数范围。Extensive green roofs have certain effect on volumetric runoff and multiple environmental and social benefits.Aiming at the problem that no detailed classification and calculation instruction are there specified in the relevant standards and specifications for the runoff coefficient value-taking range of green roof at present,a monitoring and simulation-based method for analyzing the extensive green roof is proposed herein.In order to enhance the taking accuracy of the runoff coefficient value range for the green roof,the value-taking ranges of both the runoff yield and the runoff coefficient under the condition of the event-based rainfall of green roof experimental facility are analyzed in accordance with the relevant rainfall and runoff monitoring data,and then the mean annual volumetric runoff coefficient of the extensive green roof is simulatively calculated by means of SWMM model.The result shows that the runoff control effect of the extensive green roof is better for light and medium rainfalls.Following with the increase of rainfall intensity grade,the event-based proportion of the runoff yield of the extensive green roof is gradually increased,while both the flow runoff coefficient and volumetric runoff coefficient are gradually increased as well.The value range of the peak flow runoff coefficient is 0.001 to 0.382 and the event-based volumetric runoff coefficient is 0.002~0.663.The main factors affecting the event-based volumetric runoff coefficient of the extensive green roof are the thickness of substrate layer,the type of substrate layer and the type of drainage layer.The value range of the mean annual volumetric runoff coefficient for different types of the extensive green roof is 0.104~0.324,which is lower than the range of the volumetric runoff coefficient specified in the relevant standard specifications and design guidelines.

关 键 词：绿色屋顶 流量径流系数 雨量径流系数 监测模拟 暴雨 降水 海绵城市 

分 类 号：TU992[建筑科学—市政工程]