Urban Stormwater Simulation And Waterlogging Risk Assessment Based On MIKE FLOOD

Cities are regions where environmental changes are more pronounced.Particularly in developing countries,changes in climate conditions such as underlying surface conditions and rainfall are extremely prominent.Correspondingly,the risk of flooding in cities has increased significantly,and the difficulty of simulating urban floods has continued to increase.Under this situation,how to scientifically describe the design of rain patterns to reflect the changes in rainfall climate characteristics,how to accurately identify the conditions of multivariate underlying surfaces,and to generalize the parameters,how to accurately estimate the flood risk in cities has become the city’s rain and flood simulation and Technical difficulties and focus of risk management.This paper takes the future science park area of Beijing as the research area,based on the collected basic data,builds a risk assessment model of storm flood inland based on MIKE FLOOD.In the process of model building,the study area micro-topography was appropriately generalized in light of actual investigations,planning texts,and Google Earth satellite imagery,and was divided into five different types of land-use types: architecture,roads,green space,bare land,and other land uses.The description of the regional micro-topography is based on the typical value of the impervious rate of the different types of land use given in the Classification of Current Land Use,and then the Fig.is calculated.Water imperviousness in the catchment area.For the change of climate characteristics of rainfall,the research area is located in the second zoning of the torrential rainstorm in Beijing.According to the Beijing Municipal Stormwater Runoff Calculation and Planning of Urban Stormwater System Design,the time-phase rainfall determined by the Beijing Hydrological Manual Design Rainstorm Atlas is used to determine the During the design of the rainfall process,the design rainfall at the site of the Observatory Station site was designed for 3ys,5ys,10 ys,20ys,30 ys,50ys,and 100 ys.Different design storm scenarios were set up to study the region’s storm flood simulations.Intrinsic risk assessment.Through the on-site confirmation and observation of the development status of the research area,rainfall-runoff process and diachronic intrinsic risk,the model was verified using the measured pipeline water level,the process of the pipeline outlet flow,and the depth of accumulated water in the area.On this basis,the rainfall-runoff process of the surface and the load of the rainwater pipe network system were designed to simulate rainstorms with different return periods.The hydrological response process and regional drainage capacity under different scenarios were compared and analyzed.With the return period of the design rainstorm,With the increase,the submerged area gradually expands,the node and pipeline load increase,the surface maximum submerged depth and the surface average submerged depth gradually increase;the surface submerged depth H<0.15 m area is: road and along the line and part of the low-lying area;submerged The areas with a depth of 0.15<H<0.5m are mainly along the road and low-lying areas;the inundation depth is H>0.5m,and the inner area of stagnant water is dominated by lowlying depressions and their surrounding areas.And the high-load high-end and overflow nodes are related to each other and appear in some areas.The research results are subdivided by surface submergence and pipeline load display,providing strong technical support for scientific management of regional floods,and also providing scientific decision-making basis for the development of sponge construction in the region;model parameters are based on the consideration of differences in land types.The further refinement of the spatial scale;and the model calibration method combining field surveys,measured data,and hydraulic formulas are of important practical significance for the model construction of sparsely populated areas.