The Study On Urban Waterlogging Issue Based On Urban Plannig Theory

Urban Waterlogging becomes more frequent in recent years, which arouses great attention of the whole society. It becomes a burning issue that how to solve the waterlogging problem. This thesis takes the waterlogging issue as research object, analyses the reasons for waterlogging, puts forward to the theory of "storm-water management unit", the storm-water management index system, the quantitativesimulation and the storm-water management special planning. The specific content of each part is as follows:(1) To clarify the reasons for the urban waterlogging issue based on the analysis to the waterlogging issue.Combined with the waterlogging informations of different cities, this thesis sums up the features of the waterlogging and the influence to the traffic, the economy, the personal safety and the ecolgic environment, and calrify the reasons for the waterlogging as follows: the remote causes, which include the hystereticplanning and design, the full of loopholes in construction, the inefficient management and maintainment and the lack of the relevant rules and regulations, and the immediate causes, which include the declining of the pervious surface because of the urban development, the backward drainage technique, the declining of the surface’s natural draining ability because of the changes of the site topography and the poor influence to the draining speed because of the unlimited extention of the drainage pipe net.(2)To put forward to the "storm-water management theory" and its concept, model, content and applicationBased on the system theoty and the low impact development theoty and combined with the urban planning rules in China, this thesis, with the goal of quantitatively controlling the storm-water runoff, puts forward to the concept, the model,the theoric contents and the application of the storm-water management unit. The contents include the environmental carrying capacity assessment in storm-water, the assessment and setting of the comprehensive runoff coefficient, the setting of the saturated runoff coefficient, the astabishment and the benefit evaluation of the storm-water management index system.(3) To put forward to the storm-water management index system and its composition, and discuss the relationship between the storm-water management index system and the regulatory detailed planning index system The storm-water management index system includes the comprehensive index and thesub-index. The comprehensive index is composed of the recurrence interval, the comprehensive runoff coefficient and the site vertical datas. The sub-index is composed of the building density, the greening rate, the pavement permeability and so on. To describe the method of setting each index and the relationship between the storm-water management index system and the regulatory detailed planning index system.(4) Based on the storm-water management unit theory, to simulate the benefit of the strom-water unit with different indexTo apply storm-water management model software to simulate the stormwater runoff volume, the runoff peak, the runoffvelocity and the waterloggingduration with the different index. To analyse the result of the simulation, to sum up the regular pattern of the storm-water runoffwithdifferent index, and to confirm the benefit of the storm-water management practices.(5) To put forward to the content of the storm-water management special planning and the safeguards to carry out this planningCombined with the urban waterlogging causes, the theory of storm-water management unit and the storm-water management index system, to put forward to the content of the storm-water management special planning as a statutory planning, which includes the backround and the status quo analysis, the divide of the storm-water management units, the risk assessment of urban waterlogging, the setting of the storm-water management index, the drainageplanning, the stom-water management practices and so on. At last, to discuss the safeguards to carry out this planning from the aspects of the storm-water management policy, the coordination among the different plannings and the supervisery mechanism.