Research On Modeling Method Of Structural Analysis Model Based On BIM Technology

Digital architecture has become an important strategy for the development of the construction industry,the most critical technology is BIM.Compared with the traditional CAD technology based on two-dimensional representation of point,line and surface,BIM applys object-oriented three-dimensional shape and attribute information description,which contains rich spatial information and semantic information,and has an open international data standard IFC,which makes the data conversion from BIM to structural analysis model feasible;the development of structural refinement analysis and urban large-scale building complex calculation,requires the efficiency of building structural model,which makes it necessary to study the conversion from BIM to structural analysis model.Based on the subject of "large-scale calculation and safety evaluation theory of existing building structures and foundations in coastal cities under earthquake and typhoon loads",this paper studies the modeling method of structural analysis model based on BIM,and the specific contents are as follows:1)To build a BIM-based structural analysis model,it is necessary to study the data standard of building information model and extract useful information from a large number of building information.In this paper,the industry foundation classes,the most common data standard of building information model,has been studied a lot,and the analytical method of IFC has been studied,and the entity association of geometry,material,section and other information required by structural analysis model has been summarized.2)In order to reduce the coupling degree of the program,we should avoid the direct conversion from IFC file to the data structure of the target software.This paper studies the data structure of the structural analysis model,designs the general data structure for storing the intermediate information,and realizes the interface between this model and FPM.3)The spatial location of building components is a problem that must be solved in BIM data conversion,especially the data conversion from inclined components and special-shaped components to structural model.In this paper,the reference coordinates of IFC entities with different levels are studied,and the three-dimensional restoration of spatial inclined components is realized by using the theory of affine change.Different modeling methods of BIM 3D entities have different geometric descriptions,which challenges the generality and fault tolerance of data conversion program.In this paper,the entities with different geometric descriptions of IFC and their mapping relationship with structural units are summarized,and a large number of cases with different geometric descriptions are converted to FPM platform data,which lays a foundation for the universality,fault tolerance and scalability of the program.4)The connection relationship of components in building model can not be determined accurately,which leads to the loss of connection relationship between elements in the automatically generated structural model,In this paper,we summarize the common component connections in the structural analysis model,and realize the automatic generation program of the structural analysis model considering node extraction,and verify the feasibility of the technical route of this paper through the actual engineering case.