杭州市区城西洪涝灾害防治方案研究

本研究搜集了近年来杭州城西区域遭受的较大洪涝灾害情况,分析了现状防涝能力,指出了城西防洪排涝工程的短板——下排通道受阻,提出就近深隧排洪方案(城西南排通道工程)。本研究采用一维非恒定流水动力学模型,建立杭州市运西片河网水利计算模型,分析深隧洞径和外排流量以及排涝效果。研究结果表明,实施城西南排通道工程深隧方案,隧洞衬后洞径11 m,隧洞长度约13.0 km,出口泵站设计排涝流量为200 m~3/s(远期300m~3/s),可有效减轻杭州市区城西洪涝问题,达到城区近远期水位控制目标和20年一遇以上的排涝标准。本研究为今后城市深层隧道排水系统建设积累了经验,对城市市政水利工程建设也有参考价值和推广意义。

Research on the prevention and control program of flood disaster in the west of Hangzhou City

This study analyzed the current flood prevention capacity based on the major flooding events that have happened in recent years in the west of Hang Zhou city. The results indicate that the block of drainage channel is the shortcoming of the current flooding defending projects. The study proposed the scheme of nearby deep tunnel drainage (The project of drainage channel toward the south in the west of Hang Zhou) to solve the above shortcoming. The study used a one-dimensional unsteady flow hydrodynamic model to establish a hydraulic calculation model for the river network to the west of the Grand Canal in Hang Zhou and to estimate the deep tunnel diameter, drainage flow and the drainage effects. The results show that the above proposed scheme which use parameters:a tunnel diameter of 11 m behind the lining, a tunnel length of 13.0km, and a design drainage flow of the exit pump station of 200m³/s (long-term 300m³/s) can effectively alleviate the flood problem in the west of Hang Zhou city, and achieve the goal of water level control in the near and long term and the drainage standard of more than 20-year return period. The study has accumulated valuable experiences for the construction of urban deep tunnel drainage system,and has great value to learn and can be promoted as a good example of municipal water project construction in Zhejiang province and even in the whole country.