The Analysis And Research On Urban Flood Control

In China，with rapid urbanization，the impervious area is graduallyincreasing，large areas of forest and farmland have been replaced by high-riseimpervious buildings， which makes the city’s resilience against rain stormlower，disaster of floods which brought by heavy rains has become one of themost important factors that restricts Chinese urban development．At present，although China has been strengthening the construction of urban flood controland drainage facilities，and constantly improve the normative documents suchas“flood control standard(GB50201-94)”、“outdoor drainage standard”，thefrequent urban flood disasters that happen in our country showed that thesemeasures were still inadequate．Enhancing the city’s resistibility to flood andwaterlogging disaster，we need a more scientific theory as guidance．For the above cases，this paper has done research about the followingaspects：（1）By analyzing the characteristics of urban flood and waterlogging disasters in our country，find the defects of operability in thelatest“flood control standards(GB50201-94)”and“outdoor drainage standard（GB50014-2006）”，which are used for regulating the construction of city’sflood control facilities．According to the characteristics of urban flood andwaterlogging disasters，the inundation losses caused by floods will not spread tothe entire city，but will take more serious impact to the lower elevation areas（water-logging points）in our city．Therefore，the drainaging ability ofwater-logging points must be improved to achieve the goal that protect the urbanarea from the waterlogging disaster．However，the flood control and drainagestandards in both the above two specifications are drawn up by taking all the cityas a unit．Obviously，it is not comprehensive enough to set the constructionstandards for flood control and drainage facilities by rank or town type and lackof specific guidance for urban flood and waterlogging disaster．（2）For the above defects， this paper presents the concept thatcontroling flood focused on“Water-logging point”，which points out that to it isnot necessary to improve the drainage facilities of the entire city to reduce thelosses caused by the flood and waterlogging disasters，but just taking measuresto drain away the water in“Water-logging point”is OK． Guiding with thisconcept，the investment of urban flood control and drainage facilities is greatlyreduced，which will have some practical value in terms of saving money andresources．（3）By taking Taiyuan University of Technology’s west campus as the validation region，the model about the relationship between rainfall and thewaterlogging point’s runoff、 confluence and submerged depth has beenestablished：①According to the used conditions of the models or methods that arewidely used to calculate the runoff currently and the characteristic of the textarea，chose to use the“early loss after loss method”to calculate the validationregion’s runoff．②According to the used conditions of the methods that are widelyused to calculate the confluence currently and the characteristic of the validationregion，chose to use the“isochrones method”to calculate the validation region’sconfluence．③Take twice rainfall process in Taiyuan as examples to calculate therunoff and confluence of the validation regiong，and obtain the submerged depthcaused by the twice rainfall at the outlet of the validation region according to theoutlet’s volume characteristic curves．After verification，both the two submergeddepths deriving from the calculation are consistent with the actual submergeddepth．The results of the study will not only provide guidance for theconstruction of the engineering facilities of urban flood control and drainage，which will make contribution to economy and social resources’s conservation，but also will provide program for non-engineering’s making measures，such asprovides decision support for insurance work of water-logging disaster．...