深圳地铁长圳车辆段海绵城市设施设计与施工

Design and construction of sponge city facilities in Changzhen depot of Shenzhen metro

针对中国深圳市地铁长圳车辆段可渗透下垫面少、不渗透下垫面多的实际情况,对其海绵城市设施进行优化布置和设计.除设计雨水花园、植草沟和地下蓄水模块等传统设施外,还设计了生态屋顶、高位雨水花坛和多功能蓄水池等新型海绵城市设施.采用容积法和暴雨洪水管理模型(storm water management model,SWMM)对3种设计方案的滞留能力和效果进行计算和模拟分析.结果表明,在年径流总量控制率为70%情况下,3种海绵城市设施设计方案都可以满足降雨径流不外排的设计要求.SWMM模拟结果表明,海绵城市设施可以减少长圳车辆段的径流量、径流峰值和径流系数,但随着降雨重现期的增大,海绵城市设施的削减效果逐渐降低.当降雨重现期大于等于50 a时,海绵城市设施几乎没有消减作用.综合考虑技术和经济因素,选择方案2作为长圳车辆段海绵城市实施方案.按照CJJ 82—2012《园林绿化工程施工及验收规范》和GB/T 50905—2014《建筑工程绿色施工规范》等要求,对海绵城市设施进行绿色施工.深圳市长圳车辆段海绵城市设施是目前世界上首个已建成的具有海绵型设施的地铁项目,为海绵城市理念在城市轨道交通项目中的推广应用奠定了基础.

The sponge city facilities are optimized and designed in consideration of less permeable underlying surface and more impermeable underlying surface of Changzhen depot of Shenzhen metro.In addition to the traditional sponge city facilities such as raingarden,grass planting ditch and underground water storage modules,innovative sponge city facilities such as ecological roof,bioretention parterre and multifunctional pond are designed.The retention capacity and effect of the sponge city facilities of three design schemes are calculated and simulated by volumetric method and storm water management model(SWMM).The results show that the sponge city facilities of three design schemes can meet the design requirements of zero runoff under annual runoff control rate of 70%.The results of SWMM simulation show that sponge city facilities can reduce the runoff volume,runoff peak and runoff coefficient of Changzhen depot;however,the reduction effect of sponge city facilities gradually decreases with the increase of rainfall return period,and sponge city facilities almost have no reduction effect when the rainfall return period is more than or equal to 50 years.Considering the technical and economic factors,the second design scheme is selected as the sponge city implementation scheme of Changzhen depot.According to the requirements of the code for construction and acceptance of urban landscaping projects(CTJ/T 82—2012)and the code for green construction of building(GB/T 50905—2014),the sponge city facilities of Changzhen depot as a green construction have finished and have become the first metrosponge city project in the world,which lays a foundation for the promotion and application of sponge city concept in urban rail transit projects.