关于绿色屋顶影响因素的研究

Research on influencing factors of green roof

相比于传统的在SWMM模型中添加低影响开发设施以后得出研究区域改造前后对比效果的研究,应更加了解导致产生不同结果的具体影响因素,便于以后制定"因地制宜"的海绵城市建设方案。通过采用单一敏感性分析法,对比改变单一参数得到的模型模拟结果,确定绿色屋顶的各项参数对于模型计算结果的影响。得到试验结果:粗放型绿色屋顶排水能力强,形成径流时间相比于集约型绿色屋顶提前了5min;集约型绿色屋顶的滞蓄能力高,径流总量控制率达64.4%,高于粗放型绿色屋顶对径流总量的控制率61.3%;土壤层为沙土的绿色屋顶下渗率最大,粘土最小。研究得出结论:首先在相同土壤组织类型条件下,绿色屋顶的土壤层厚度对于降雨径流的影响最大,其次是同一降雨事件发生在同一个屋顶的情况下,土壤层土壤组织类型会对降雨径流影响,最后植被容积小数虽然在模型中对于结果的影响并不大,但是在现实生活中由于植被根茎对于雨水的滞留和对土壤的团化作用,也有着十分重要的影响。

Compared with the traditional research on the comparative effect of the research area before and after the transformation after adding the low impact development facilities to the SWMM model,we should know more about the specific influencing factors that lead to different results,so as to formulate the sponge city construction plan of"adjusting measures to local conditions"in the future.By using the single sensitivity analysis method and comparing the simulation results obtained by changing the single parameters,the influence of the parameters of green roof on the calculation results of the model is determined.The experimental results show that the drainage capacity of the extensive green roof is strong,and the runoff time is 5 minutes earlier than that of the intensive green roof;the storage capacity of the intensive green roof is high,and the total runoff control rate is 64.4%,which is higher than that of the extensive green roof,which is 61.3%;the infiltration rate of the green roof with sand layer is the largest,and the clay layer is the smallest.The results show that:firstly,under the same soil organization type,the thickness of soil layer of green roof has the greatest influence on rainfall runoff,secondly,under the same rainfall event on the same roof,the soil organization type of soil layer will have an influence on rainfall runoff,and the last vegetation volume fraction has little influence on the results in the model,but it is in reality The roots of vegetation also have a very important influence on the retention of rainwater and the aggregation of soil.