Safety Evaluation Of Urban Underground Pipeline Spatial Layout Based On GIS

With the rapid development and constant expansion of urbanization,urban underground pipeline has been the important supporting infrastructure in cities.It develops so fast that various underground pipeline networks crisscross and extend to every corner of a city.However,more and more security incidents of underground pipelines have occurred with the increase of pipelines.The security risk has already been a great threat to urban development in China.According to many accidents of urban underground pipelines in recent years,problems existing in spatial layout are among the main sources of underground pipeline security risks for the pipeline system with all kinds of highly correlative pipelines is crisscrossed,widely distributed,strongly public-functioned and highly vulnerable.The underground pipeline security in spatial layout is closely related to urban security.On the one hand,urban development promotes the construction of infrastructure facilities.Accordingly,the scale of underground pipelines will enlarge and the spatial layout will constantly change.On the other hand,underground pipeline construction will influence urban expansion,and then urban construction and underground resource development will be restrained by the existing spatial layout of underground pipeline.Therefore,the research on the spatial layout of underground pipelines can provide scientific,quantitative and spetialized security information for planning department.Besides,the research also provides a scientific basis for underground pipeline planning,construction,operation and management,especially for maintenance,transformation,and prevention scheme making.It is of great scientific and practical importance to ensure life and property security as well as urban sustainable development.In this research,evaluation indexes with higher impacts on underground pipeline security are determined according to features and rules of spatial layout.The analytic hierarchy process is further employed to confirm evaluation factor weights,establish the security evaluation system of underground pipeline spatial layout,create the index evaluation model and comprehensive evaluation model,and finally realize the security evaluation of spatial layout of urban underground pipeline based on GIS.In the end,with a combination of engineering examples,security analysis of underground pipeline spatial layout in certain region of city W is accomplished with good evaluation result.The evaluation theory and method of this research have been verified reliable.This paper mainly includes the following parts:(1)Domestic and overseas literature and documents related to pipeline security evaluation are investigated.The acquired research achievement and development direction are analyzed to discover the imperfect of existing research and then put forward research content and method about the security of urban underground pipeline spatial layout based on GIS.(2)On the basis of fully grasping of underground pipeline spatial layout features,four evaluation indexes-occupation,clear distance,laying sequence and laying depth are put forward according to its rules and requirements with available data.The weights of effect degree of each index on spatial layout security are determined with analytic hierarchy process.(3)Based on GIS analytical method and according to varying indexes,analytical models are constructed,and implement methods of analysis are explored.Multi-factor comprehensive evaluation models are constructed based on the single factor analytical model.(4)In the research,according to the security evaluation method of underground pipeline spatial layout based on GIS and the specific situation of underground pipeline in city W,the analysis is realized in respect of such risks as underground pipeline occupation,clear instance,laying sequence and laying depth,as well as the overall condition of spatial layout security in certain religion of the city.The analysis result is output into visualization representation,and is submitted to corresponding urban planning department.It has been verified that the research result is accordant with the practical situation of construction and development of the experimental area.