Integrated Modeling and Calculation of Urban Surface and Underground Flooding.

Due to the rapid urbanization and heavy rainfall, urban flooding on ground surface and in underground spaces is increasing. Based on the formation mechanism of urban rainstorm waterlogging, an integrated model and calculation method for urban surface flood and underground spaces is built. The method integrated coupling hydrodynamic model and underground space flood generalized calculation model. Coupling hydrodynamic model integrates one dimensional (1D) storm water management model (SWMM) and two dimensional (2D) flood routing model. The overflows at the manhole due to exceeding pipe capacity were calculated through rainfall-runoff analysis with SWMM, which is a 1D dynamic urban storm water system analysis model. Then, an urban flood analysis was built by utilizing the manhole overflows as boundary conditions in the 2D overland flood model. The linkage process between 1D SWMM and 2D overland flood model was linked by boundary condition. Generalized calculation method to account for Maximum hazard frequency of rainfall, flood flow entered into underground space, and floodwater level rising velocity in underground space. The process of waterlogging in the urban area is simulated by using the observed rainstorm process, the results prove the effectiveness of the integrated model. [ABSTRACT FROM AUTHOR]