关键词: 排水系统;排水能力;内涝防治;地表水动力模型;管网模型;镇江市;

Abstract: In recent years，heavy rain has occurred frequently.Therefore，it is of great significance to evaluate and optimize the drainage system in urban areas for waterlogging prevention.Taking a flood control demonstration zone in Zhenjiang City as the research area，a land surface-pipe network coupling model with urban pipe network model and two-dimensional hydrodynamic model was constructed to simulate the drainage system and evaluate the improved effect.The results show that there are over 60% of pipelines with drainage capacity less than 5-year，which means that the drainage capacity is obviously insufficient.In the rainfall scenario of 50-year，the accumulated water area reaches 686 000 m2，accounting for 9.94% of the whole flood control demonstration zone.The Wanda Plaza，west of the Huangshan South Road，Tianqiao Branch Road and its east are the serious areas of waterlogging areas.Accordingly，an optimization scheme of a new rainwater pipe with diameter of 600 mm and length of 9.5 km and a rainwater grate was evaluated.The simulation results show that the optimization scheme can reduce the operating load of the upstream and downstream pipe network on the overflow well，and alleviate the fullness and overload of the pipe network.Overall，the coupled model can effectively assess the current status and capacity of the drainage system in the flood control demonstration zone.The new model can be used in the optimization and transformation design of the urban drainage pipe networks，and can also provide technical support for the prevention and control of urban waterlogging.

Key words: drainage system；drainage capacity；prevention and control of urban waterlogging；surface hydrodynamic model；pipe network model；Zhenjiang City