深隧排水系统在城市内涝防治中的作用分析

Effects of Deep Tunnel Drainage System in Urban Waterlogging Prevention

深隧排水系统是一种行之有效的内涝防治工程措施,但目前国内相关的研究尚比较少,大规模深隧排水系统的应用效果及机制尚不明确.本文利用IFMS URBAN洪水模拟分析平台构建了分布式城市水文水动力模型,以成都市为例,研究深隧排水系统在城市内涝防治中的作用.设置了多种降雨情景和工况组合情景,对有无深隧条件下研究区内涝积水情况进行模拟,开展了多组模拟结果的对比和分析.结果表明:在30年一遇降水条件下,深隧服务范围内减少了31.4%的溢流点、50.5%的溢流水量,积水情况大大缓解,其服务范围内严重内涝问题基本得到控制;深隧排水系统削减城市内涝的作用随降雨重现期的增大和降雨峰现时间的延后而减弱;深隧系统中的蓄水池与泵站组合对深隧的作用具有较大影响.

Deep tunnel drainage system is one of the effective measures for waterlogging prevention and control,which is scarcely discussed in China.The effects and mechanisms of large-scale deep tunnel drainage system have rarely been analyzed yet.To illustrate how the deep tunnel drainage system performs on urban waterlogging prevention,this paper built a distributed urban hydrology-hydrodynamics model in Chengdu by using IFMS URBAN.Several scenarios of rainfalls and operating modes were simulated to compare the waterlogging conditions in the study area with or without the deep tunnel drainage system.The results show that under the 30-year rain events,the deep tunnel system reduces 31.4%of overflow nodes and 50.5%of overflow volume,which greatly relieve the water accumulation condition.It indicates that the deep tunnel system could basically control the serious flooding in scope of its work.With the increase of rainfall intensity and the delay of rainfall peak,the effects of the deep tunnel system decrease in terms of reducing urban waterlogging.The combination of underground storage and pumping stations has great influence on the effects of deep tunnel system.