Key Technology Of 3D Urban Underground Pipeline GIS

Urban underground pipeline network Composed by Comprehensive staggered water supply,drainage,gas,heat,electricity,communications,telecommunications,industrial pipelines and other types of composition,It is an important part of urban infrastructure,which bears the city's information delivery,waste disposal,drainage mitigation,energy transport,etc,is regarded as the city's "lifeline." With the rapid development of urban construction,many cities have research and established adapt to the situation of the city's underground pipeline 3D GIS for urban underground pipelines scientific and effective management.However,the existing urban underground pipeline GIS are mostly based on a two-dimensional plane of expression,this expression does not accurately describe the complex spatial relationships between underground pipelines,therefore,3D urban underground pipeline GIS study appears increasingly urgent.The paper rely on "Luoyang underground pipelines and underground space Census Integrated Management Information System" project,in summarizing the current construction of digital cities,analysis the current situation and problems of 3D urban underground pipeline GIS key technique to study the three-dimensional city underground pipeline GIS implementation process in a number of key technologies,design and implement a prototype of 3D C ity underground pipeline GIS system.The main contents of this paper include the following aspects:First,to improve the efficiency of building model,reduce repetitive work,The paper proposed a three-dimensional model of the tube design and modeling program and use 3DS max software build 14 standard pipe three-dimensional model for invoke modeling.Based Arc Engine component technology and Geodatabase data model to study the use of two-dimensional vector data to build the pipeline model of urban underground pipeline dimensional approach.Taking into account the relationship and the integration of underground and aboveground pipelines feature shows the use of the ground surface features studied two-dimensional vector data to build a one-sided,and then stretched its combined operations,such as a method to build a three-dimensional model of the ground surface features.Second,in order to solve the problem of the tube model in the face of complex and diverse underground pipeline connection can not fully express the studied pipeline modeling algorithm convergence,according to the different diameter pipeline will be divided into equal-diameter pipeline modeling convergence and different modeling diameter pipelines converge modeling categories;studied the convergence of equal diameter pipeline modeling method for reducing line interface modeling,design of a triangle in the construction of the pipeline through the convergence of the cylinder,the cylinder diameter draw bending combination algorithm to solve the smooth lines converge at the modeling problem.Once again,the status quo of urban underground pipeline burst pipes frequent accidents,taking into account the traditional analysis based on low-dimensional squib efficient way to graph theory,the result is not intuitive defects Arc GIS network flow model to study the design of the network flow model based on the three-dimensional analysis of the implementation strategy burst pipes,burst pipes studied the effects of three-dimensional analysis of the user area to achieve a three-dimensional scene analysis off valve pipeline burst pipes and affect the user area analysis,provide a basis for decision support departments.For urban construction in the blind lead the excavation of underground pipelines easily digged inadequate design and implementation of ground excavation simulation algorithm used to determine whether the pipeline excavation space by achieving a comprehensive display of three-dimensional space of the excavation;study the three-dimensional attribute query method and three-dimensional scene length,area,volume calculation method.Finally,the design and implementation of a three-dimensional urban underground pipeline GIS prototype system,which includes a three-dimensional scene is displayed above and below ground,three-dimensional analysis of burst pipes,burst pipes affect the three-dimensional analysis of the user area,ground excavation simulation,three-dimensional attribute query,calculate the amount of space,such as three-dimensional modules.By these features,verify the correctness of the content thesis and availability of the system to achieve the desired effect.