BIM Model Components Retrieval Method Based On Spatial Relation

BIM technology is an important means of realizing the deep integration of traditional construction industry and Internet and upgrading and transformation of industry relying on advanced technologies such as big data,cloud computing and artificial intelligence.BIM is a digital expression of the building and its functional characteristics to support the entire project decision.The core of BIM technology application is the component-based visual 3D model with various types of information.Such data is defined according to certain rules to support its application and exchange.The data characteristics of BIM model components determine that they can participate in multiple workflows,such as structural calculation,energy consumption analysis,cost statistics,prefabrication of assembly components.Therefore,the research on the interaction of BIM model component has gradually become a popular research direction in order to maximize the use of information.The purpose of this thesis is to realize the interactive retrieval of BIM model components.In practical application scenarios,such as inspection,fire protection and equipment replacement,retrieval will help users improve the efficiency of target component information acquisition and reduce information screening costs.Aiming at the problems existing in the traditional keyword retrieval methods currently used,such as semantic ambiguity and disorder of retrieval results.According to the spatial characteristics of BIM model components,a special retrieval method of BIM model components is proposed to solve the above problems.The main research work is as follows:(1)In this thesis,the characteristics of the core three-dimensional visualization model of BIM technology and spatial relations of components are analyzed.Based on its IFC data standard,the geometric definition method and attribute definition method of BIM model components are summarized,and information extraction and utilization methods are proposed.Finally,the spatial relation of BIM model components is summarized to provide a basis for the implementation of retrieval methods.(2)A query method of BIM model components retrieval based on explicit semantic analysis is proposed.By using the semantic interpreter based on IFC standard,the input query and the components to be retrieved are mapped to the semantic vector space.By maximizing the understanding of query semantics,the most relevant query results are returned.(3)A recommendation algorithm of BIM model components retrieval based on spatial reachable distance is proposed.Specifically,a method of extracting world coordinates of components is proposed,and a user reference point definition method is proposed to represent the user’s position in the model space.Then,a definition method of spatial reachable distance based on indoor public space road network is proposed,which is used to rank the retrieval results of components and return the optimal retrieval results.Based on the proposed method,using WebGL technology,REST architecture and NoSQL database and other related technologies,the interactive retrieval platform is implemented.Finally,the retrieval method is validated by the actual project models.Theexperimental results show that the proposed retrieval method produces more relevant results and meets the needs of users,so that users can quickly,timely and comprehensively obtain the required components information.