| Recently, it seems that extreme stormwater attacks us frequently and rainy seasons come in advance. With so fast urbanization, great changes that imperviousness factor increases evidently have taken place in ground of towns and thus there is a great challenge for flooding precaution. Urban road waterlogging is typical representation of urban flooding and has taken more attention of municipal governments, relevant researchers and citizens.Whilst we analyzing planning and design rationality according to simulation that how does the stormwater network system go on with extreme rainfall and evaluating and tabling a sound proposal for municipal maintenance to cope with urban road waterlogging, it is urgent to establish a platform of data importing and visual representation of hydraulic computing. Then we can make out area, volume, height and duration of waterlogging and offer some engineering and non-engineering measures to minimize waterlogging damage.Firstly, there is a great gap between domestic and alien academic circles in outdoor drainage system planning and design theory and practice. Ecological environment, rainwater detention, methods updating of design and calculation, usage of computer models, design calibration, risk evaluation and maintenance have been take into account in corresponding foreign theory. Rational method has already been limited within small scale catchments. However, computer situmulation technologies based on non-steady flow theory, rather than rational method, are employed for vast scale catchments. Besides, all catchments have to been calibrated through computer simulation methods.Secondly, with analysis of the domestic and foreign theories and standards of stormwater system planning and design, the thesis presented stormwater network system evaluation framework and studied on evaluation flow and content. According to content of evaluation framework, evaluation index were sorted into three administrative levels, initial and calibration index in phase of design standard evaluation, precaution index in phase of flooding standard evaluation. In addition, this paper explored how to ascertain full load, surcharge, waterlogging, sub-flooding and flooding states according to the change of gravitated to pressured flow and criterion of 15cm in height and 30min in time. Practically, it is beneficial to improve criterions and establish flooding precaution scheme in case if we evaluate the planning, design and maintenance of stormwater network systems and analyze risks of extreme stormwater disasters with computer models.Thirdly, with above analyses, this thesis studied how to manage graphical and attribute data based on GIS and described distribution of waterlogging sites. I compartmentalized road surface by 1×1m grid, computed these elevations by a computer program and saved them into a database, combined and imported graphical and attribute data of road from CAD environment to ArcGIS environment in order to get road data model. At the same time, I studied how to describe graphical and attribute data of stormwater system based on GIS and presented establishment method of stormwater network system data model. Then, urban road waterlogging data model was coupled via node and node controlled area. Actually, the data model was employed for stormwater system of Laoshan Olympic stadiums and neighbor area with outstanding performance. In brief, it can be used as data importing interface and visualization platform. So, of course, it is the foundation for study on urban road waterlogging.Some key issues in the thesis can offer reference for modifying domestic outdoor drainage design specification, establishing visual representation platform for digital monitor system of flooding precaution and drainage, and analyzing rationality of urban stormwater network system and ability of flooding precaution. |
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