GIS-Based Analysis Of Three-Dimensional Underground Pipeline’s Burst And Its System’s Design And Implementation

With the rapid development of economy these years, the urbanization process of our country is pushed head continually. The underground pipeline, with their amounts and length increasing rapidly, are the important components of the urban infrastructure. The various underground pipeline bring much convenience to the human daily life, however, pipe explosion accidents triggered by various reasons bring much threat to social property and personal safety. Managing the huge and complex information of pipeline scientifically and efficiently, acquiring dynamic condition of pipeline, trying the best to ensure the steady, safety and high efficient operation of pipeline are the important work of underground pipeline managers as well as the essential requirements of the sustainable development of cities.This thesis is based on GIS technology, and an underground pipeline system with the integration of two-dimension and three-dimension is designed and developed which is based on the actual demand of underground pipeline management. The system is a secondary development which is based on the platform of 2-D Arc Engine and 3-D Terra Explorer Pro. The main research work contains: the comparison of the changing of platforms by CAD data, the reasonable preprocessing of underground pipeline observational data by using Arc GIS Desktop, and a data format that is suitable for GIS system is obtained; a “Two Point Make One Line” pipeline data structure is designed; in the analysis of pipeline explosion, the disadvantages of traditional “Valve Shut Off” algorithm for pipe explosion are analyzed, and the improvement solution is given that considering the direction of pipeline carrier, the BFS algorithm is improved based on the pipeline digraph; besides, the explosion of burning pipeline with large damage is especially analyzed, the diffusion situation of combustible gas is simulated in the 2-D scene in accordance with combustible gas leakage model, gauss diffusion model and secondary development of Arc Engine; the diffusion region is divided based on the range of gas concentration, and the proposed valve shutoff search for the flammable and explosive pipeline explosion with great damage should consider the other valve nodes that are near to the place of pipeline fracture but are not connected with other valve nodes.The underground pipe information system developed in this thesis has achieved the three-dimensional reappearance of underground pipeline distribution, and accomplished the function of query, analysis and statistics of the pipeline spatial information and property information. In the part of pipeline explosion analysis, the modified breadth-first search algorithm has achieved more accurate query results, and the GIS simulation of combustible gas diffusion after pipeline explosion provides reliable substratum for the division of dangerous region.