The Study Of A Southern City Water Supply Pipeline Network Health Evaluation Index System And Model Construction

Maintenance and transformation of water supply pipe network is an effective means to ensure the safety of water supply. While the formulate of maintenance and transformation plan for pipeline network requires a comprehensive understanding of its health status, in order to determine the means and orders of pipelines’ maintenance and updates. The study of water supply pipelines’ health evaluation techniques can reduce the human and material resources of traditional manual inspection, improve the management level of water supply network and maximize the use of limited resources, which has great significance for improving water supply safety and enterprises economic efficiency. In this paper, the construction of water supply pipeline network health assessment index system has been researched, by the analysis of influencing factors for a southern city’s pipeline health.Firstly, this study based on the city pipeline network’s attribute and maintenance data examine the impact of various factors on the health of the water supply pipeline from the basic properties and hydraulic characteristics respectively. The effects of each factor on the pipeline health express as that the accident probability decreases with the diameter increasing and the failure probability of pipelines with larger diameter is far less than the ones with smaller diameter. The accident probability of various pipe rang with descend order, which shows as:steel pipe> gray cast iron pipe> concrete pipe> plastic pipe> ductile iron pipe. With the pipeline age increasing, the pipeline failure probability rises slowly, while it decreases slowly with the depth increasing. And the welded pipelines’failure rates is higher than the other interface modes. Water pressure fluctuation has a certain influence on pipelines’health, shows as the greater the fluctuation, the more exploding and leaking.Secondly, the water supply pipeline network health assessment index system is constructed by the improved AHP (Analytic Hierarchy Process), which is based on the fuzzy evaluation matrix, and gray correlation method. Use the method of operating data statistics to instead the expert score to construct the fuzzy evaluation matrix, so as to arrive the weight distribution of water supply pipeline health assessment index system, which shows as: diameter=0.2051, pipe material=0.3663. pipe age=0.2150. burial depth=0.0714and interface mode=0.1427. Use the correlation coefficient as the evaluation criteria for the merits of the pipeline health status, and select the factor of each index with the lowest failure probability as the reference sequence. Combined the index weight and correlation coefficient to compose the health factor of each factor, in order to calculate the pipeline health degree and propose the maintenance measures for different levels from1to5, which rank by the value of health degree from more to less.Thirdly, use the Visual Basic6.0and Microsoft Access database as the tool to develop the water supply pipeline health assessment system to achieve the evaluation parameters by increasing the pipeline failure data updates, constantly rationalize the evaluation system and realize the calculation of pipeline health degree and classification of health level, in order to facilitate the engineering applications.Finally, consider from running data management, pipeline network diagnosis and update and maintenance strategy to integrate the research achievements on water supply pipeline network transformation and diagnostic techniques of our group and this study, thus to propose the integration scheme of water supply pipeline renovation and diagnostic system, in order to improve the level of daily management of pipeline network.