城市雨水利用工程设计中的若干关键技术

随着我国城市化进程的加快,城市不透水面积增加导致雨水排泄负担加重,城市内涝更为严峻和频繁。城市雨水利用作为缓解这些问题的一项重要措施在我国逐步受到重视。由于缺乏系统、完善的工程设计方法,该项技术推广应用的速度、范围和效果受到限制。依据北京10年来的研究成果和工程设计与建设经验,探讨了雨水利用工程设计中的设计降雨、雨水池容积、溢流堰标高、调控排放调蓄池容积、绿地下渗设施规模、透水地面结构等技术关键的计算、设计方法和技术要点;提出了通过时间频率曲线推求较短历时设计降雨过程的方法;将雨水池的容积分成回用容积和调蓄容积,应用逐日调节计算法和数值模拟法分别进行计算;提出了调控排放系统调蓄容积的水量平衡估算法;建立了透水砖地面的设计流程。成果可为指导城市雨水利用工程建设、促进城市雨水利用技术的推广提供技术支撑。

Key techniques in designing rainwater harvesting works in urban areas

With the rapid progress of urbanization in China,rain water drainage stress increased and water-logging occurred more frequently in downtown.Therefore,rainwater harvesting in urban area,as one of the effective measure to solve these problems,has been pay more attention,and has become a hot point of research and application.For this reason,on the basis of research results and engineering design and construction experiences in the past 10 years,some key techniques of designing rainwater harvesting engineering in urban areas were summarized,such as design storm determination,calculating and determining storage volume of integrated rainwater tanks,elevation of overflow weir,infiltration devices and permeable pavements.The design rainfall process can be obtained by DDF curve.The storage volume of rainwater tank can be divided into two parts,namely rainwater reuse volume and detention volume.Rainwater reuse volume can be determined by daily adjustment calculation method,while detention volume can be determined by numerical simulation method.The detention volume of detention and controlled discharge system can be determined by water balance method.The Design process of pervious pavement has been put forward.