Design Storm Pattern Analysis In The City Of Beijing

With the rapid development of Beijing urban construction, the frequency and spatial distribution of precipitation are constantly changing, previously urban sewerage system standards have been unable to adapt to the development of Beijing city now. Therefore, according to the current statement of Beijing, rainwater exclusion design standard should be re-amended.Given the above situation, in this thesis, it relying on the project, which is Led by the Beijing planning committee, combined the Beijing meteorological bureau, Beijing municipal drainage and Beijing municipal drainage group and so on several units, the name of which is Beijing urban rainwater exclude planning and design standard research. Based in Beijing, using the method of mathematical statistics, the paper analyzes by-minute data of multiple stations and short duration rainfall data of a number of hydrological stations. By Extracting parameters of rainfall in Beijing, counting and classifying the actual process of rainfall, establishing distribution of storm pattern design of 5-minute units of time and the surface distribution of design storm pattern, it explored and did research on the rational allocation and management of water resource as well as providing basic technical support for flood control planning. In this project, I was responsible for information search, data processing and calculation, the result collation.The data collected in this thesis include rainfall original data, relevant literature data and results, and related "norms" and "Manual" and so on. The original data used for rainfall research comes from meteorological stations and hydrological stations in Beijing with good integrity.Refer to the design and application of urban rainfall water exclusion system, this thesis selected 60 minutes,120 minutes,180 minutes and 24 hours as the time point to analyze the distribution of stormwater. By using Pilgrim & Cordery method, with the same frequency analysis method we calculated three shrot duration rainfall pattern including 60 minutes,120 minutes and 180 minutes to get the Beijing's 24-hour design storm rainfall patterns.The conclusion is as follows:①The 24 hours(1440 minutes) design stormwater pattern is consisted of two peaks, the occurrence time of 52 hours (260 minutes) and 204 hours (1020 minutes, the main peak)②The short duration pattern lasted for 180 minutes, with 63% single peak pattern proportion and the 120 minutes with about 76% single peak pattern proportion while 60 minutes with up to 85% single peak pattern proportion. Among the single peak rainfall patterns, the majority peak rainfall occurs in the front and middle of the rainfall, and only a few in the later. Among the bimodal or trimodal rainfall patterns, the majority peak rainfall also occurs in the front and middle of the rainfall. All the short-time design storm rainfall distribution patterns are single peak rainfall.The peak design storm rainfall occurs in the first 5 hours(r=0.42) in the 60 minute and 120 minute design patterns, while occurs in the first 7 hours(r=0.19) in the 180 minute design patterns.On the basis of many years (1956-2008) rainfall data of Beijing, this paper has been studied, summarized the spatial and temporal distribution discipline of rainfall, and preliminary analyzed impact factor of heavy rainfall in Beijing. The principal component analysis, contour map, contour map of the percentage anomaly methods were applied for analyzing the rainstorm characteristics qualitatively and quantitatively.①DistrictⅠ:Hill back the wind zone. The upper boundary is the city boundary, the lower boundary is the zero line of isogram for percentage of 1 hour precipitaion departure of rainfall;②DistrictⅡ:Piedmont plain. The upper boundary is the isogram for percentage of 1 hour precipitaion departure of rainfall, the lower boundary is the upper boundary of districtⅢandⅤ;③DistrictⅢ:The west of pinggu, the east of shunyi and the south of miyun. The upper boundary is the isogram for percentage of 1 hour precipitaion departure of rainfall, the lower boundary is the city boundary;④District IV:daxing and Surrounding areas. The upper boundary is the isogram for percentage of 1 hour precipitaion departure of rainfall, the lower boundary is the city boundary.