Seismic Function Evaluation System Study Of The Water Supply Network Based GIS

Water supply system is an important part of the lifeline systems in modern city. It is significant to analyze and estimate rightly the service capability of the water supply network before and after the earthquake. In addition, it is also an important problem part to study the pipe network design and enhance seismic resistance of the pipe network. Aim of this paper is as follow: based on the relatively mature theories and secondary development of MapBasic and Fortran, a seismic function evaluation system of the water supply network is established. This system is used to evaluate the seismic function and the damage degree of water supply network, which is of great importance in guiding the water supply networks' seismic design, the water supply networks' seismic performance prediction, and the efficiency improvement of the post-earthquake restoration.Firstly, the seismic performance of single pipeline is done in the paper. The damages of the pipelines and its affecting factor are discussed, and the effect seismic wave-propagation is considered mainly in the analysis.In the second part, based on the analysis result of the single pipeline, the connectivity reliability analysis is made. On the basis of the water supply network model and fuzzy graph theory the connectivity reliability analysis method, Monte-Carlo method, is introduced.In the third part, hydraulic analysis for the water supply network is carried out. The hydraulic analysis methods for the network before and after earthquake are discussed respectively. At the same time the available leakage model is improved, and the new analysis model is proposed. An example is illustrated to confirm the method feasibility. Analysis in this part has prepared for the establishment of the seismic function evaluation system.In the fourth part, GIS based seismic function evaluation system of the water supply network is established. Firstly, the foundation database is developed, and then the connectivity method and hydraulic analysis method of water supply network in various damage states are developed into dynamic link library and then inserted into the MapInfo platform, and the seismic function evaluation system of the water supply network is established finally.To demonstrate the method and program, the seismic function evaluation of some city's water supply network has been made in this paper, and the results showed that the evaluation system is robust and efficient.