高密度老城区海绵城市径流控制研究

针对老城区海绵城市建设缺乏专项治理措施的现状,为了解决老城区海绵城市建设的内涝问题并实现径流控制,基于老城区以问题为导向,以点带面的基本思想,同时考虑高密度老城区人口密度大,改造难度大和遗留问题多等特点,海绵城市建设需要因地制宜,采取合理有效的技术方案实现对老城区的径流控制。以国家首批海绵城市建设试点城市萍乡试点区中的典型老城区西门内涝区为例,提出针对高密度老城区海绵城市建设的径流控制方案,主要包括源头地表绿色设施的减量控制以及末端地下调蓄设施的二次控制。总结了地表绿色设施组合的技术思路,介绍了地下调蓄设施的计算方法、布设以及抗浮设计等。结果表明:高密度老城区径流控制不能单靠绿色设施进行源头控制,也需要地下调蓄设施进行末端治理,其中单靠绿色设施实现了55.7%的径流控制率,加上地下调蓄设施后完成了75%的径流控制目标。该方案为类似老城区径流控制提供了可借鉴、可复制的成功经验,对老城区海绵城市建设径流控制具有重要的参考意义与实用价值。

Study on runoff control for sponge city construction of high-density old urban district

Aiming at the status quo of the sponge city construction of old urban district without specific improvement measures, the runoff control of old urban district is necessary to be realized with the relevant reasonable and effective technical schemes for the construction of sponge city in accordance with the basic idea of“orienting by problem and fanning out from point to area”for old urban district and the simultaneous consideration of the characteristics of high population density,large difficulty of improvement,more residual problems concerned,etc．,so as to solve the problem of waterlogging and realize runoff control for the construction of sponge city for old urban district． By taking the Ximen waterlogging area of the typical old urban district within the pilot areas of Pingxiag City—one of the first batch of pilot cities for the construction of sponge city in China as the study case,a runoff control scheme for the sponge city construction of the high-density old urban district is proposed herein,which mainly consists of the reduction control through the source surface green facilities and the secondary control through the terminal underground regulation and storage facilities． Moreover,the technical ideas of the combination of surface green facilities are summarized,while the calculation method,the layout and the anti-floating design for the underground regulation and storage facilities are described as well． The study result shows that the runoff control of the high-density old urban district can not only rely on the source control through green facilities,but also needs the terminal control through underground regulation and storage facilities,in which only 55. 7% of the runoff control rate is realized with the green facilities and 75% is achieved after adding the underground regulation and storage facilities． The scheme provides a referable and reproducible successful experience for the runoff control of similar old urban district and has important referential significance and practical value for the runoff control of the sponge city construction of old urban district．