Study On Urban Water Supply Pipe Network Leakage Evaluation Based On GIS Technology

Urban water supply has become sustainable urban development and construction of the important constraints, which is the lifeline of the city and to protect people's lives the essential material basis of production. It is directly related to the social stability and economic development. Urban water supply network is a major component of the water supply system. A good pipe network and the management of urban water supply will be directly related to the social and economic benefits. However, urban water supply pipe network in the course of its operation, as some can not be predicted and can not control factors, would inevitably met with a certain degree of damage it and cause running water leakage.Over the years, pipe network leakage has been the impact of water company the biggest problem of poor sales. Reducing it has become one of business problems to be solved. At present, leakage control is mainly to develop a number of leak detection methods and leak detector device, which is based on the recognition of pipe network leakage at home and abroad. But, these methods and equipment all have some problems, such as large investment, low precision, the microscopic effective and so on.The main purpose of this paper is judging the possibility of water the size of the leakage, which is based on conducting leakage factor analysis, and putting the evaluated results into practice. How to correctly analyze and evaluate the ?leakage of water supply situation have great significance on the entire water supply network of the leakage control, and can be used by water supply companies to make decisions, like leakage detect, pipe network replace and so on, as the important basis.Firstly, a large number of sewer leakage on the basis of the data, this paper analyzed the various factors which affect the pipeline leakage, and made a number of pipeline leakage control measures. Leakage factor analysis carried out in order to better understand the mechanism of pipeline leakage. It is found that the situation near the soil pipe laying and the water pressure in pipe are the main factors. Soil conditions can cause other factors of leakage, such as foundation settlement, the interface forms, external pipeline corrosion and other changes, and when pipe laying is completed, water pressure is the only changes factor in a short time among a number of factors. Pipe laying period appears to close with the leakage, but studies show that is not significant relation between them. These results are the basis of selecting the evaluation factors, determining the weight factor and structure factor evaluation matrix in the leakage of the evaluation process.Since the leakage evaluation is a fuzzy event, the evaluation result should be expressed by fuzzy language, therefore we selected as the fuzzy comprehensive evaluation method for leakage evaluation model. This paper also analyzed by comprehensive evaluation of several elements needed in detail (including the reviews set, factor set, the weight factor and evaluation matrix). Secondly, the weighting factor for the general methods such as expert scoring with a certain subjectivity, this level of analysis is selected as the method of calculating the weight factor, which makes weight distribution more reasonable.Taking into account for the large and more complex basic data of evaluation in water supply pipe network, this paper analyzed the advantages of water supply network GIS. Then, it presented GIS as a platform to build evaluation model of vision, and the GIS platform module integrated evaluation and feasibility analysis required.In this paper, conclusions are made:1) After a lot of data on the findings of a study of factors affecting leakage of pipe network is mainly soil properties and water pressure, which is generally believed that a large influence service life and no significant leakage between the relations;2) The fuzzy evaluation method combines both the subjective judgments into another mathematical method, which avoids the possible errors of subjective judgments, but also reduced in the absence of sufficient data over-reliance on mathematical error appears;3) Based on this analysis of data leakage factor, the leakage of water supply evaluation process has been studied, and for the membership function of the grade point difficult to determine were simplified, that is based on data analysis factor score, determine the degree of membership of a single factor;4) The combination of pipe network data analysis using the AHP method to determine the evaluation process as a factor for weight method. AHP method to achieve a qualitative analysis and quantitative analysis of the combination, compared to the weight distribution of expert scoring method is more reasonable;5) Studied the secondary development of GIS system's possibility, and it is feasible that other functions integrated in the GIS; made assessment of the needs of leakage analysis in the GIS system for future builds evaluation module provides a thought.Above study presented a practical method for the leakage of sewer evaluation, and provided a train of thought for controlling leakage of water supply enterprises.