Study On Configuration Elements Of Skeletalstructures And Generation Of Structure Shape

With the acceleration of urbanization,also benefited from the development of design synthesis and computing tools in recent years,a large number of magnificent and distinctive large-span space structures have been built in China.Due to the advantages of light weight,large rigidity and novel appearance,skeletal structures are widely used in space structures.Therefore,the conceptual design is becoming more and more significant.Analyzing the structures by computers is very common,however,it is too difficult to use the computer simulating human’s brain to do the conceptual design,for realizing the automatic generation of the structure in order to provide more options.Based on this problem,the automatic generation of plane truss has been realized abroad,but the research on the method in China is rarely seen.This paper focuses on introducing the shape grammar theory into the design and generation of skeletal structures,by studying the morphogenesis method of skeletal structures at home and abroad.Through studying the classification of the spatial structures and its configuration elements,selecting the plane branching structure and the spatial grid structure as the research object which has high repeated basic cells,establishing the shape grammars rules for them.For the plane skeletal structures,the topological form of branching structure is generated by using the established shape grammar rules.The ratio of the structural strain energy decline to the self-weight is introduced as the criteria to evaluate the performance of structure,and the stress ratio of structural component is applied to guide the application of grammar rules.The results show that compared with the conventional method based on shape grammar,which randomly selects the structural parts to use the shape grammar rules,it is more efficient for improving the structure to use the stress ratio as a guidance,based on evaluating the structural performance after using the shape grammars.The constructed shape grammar rules proved to be applied to the topological generation of the branching structures.For the space skeletal structures,this paper takes the spatial truss beam as an example,gives the generation of using established rules,and analyze the model of key steps based on ANSYS.The result show that a grid structure with certain optimization characteristics can be generated by the shape grammar rules.Based on constructed half surface data structure,this paper also realizes the digitization of shape grammar rules by c++ programming language,through establishing interface in Microsoft Visual Studio 2012,the graph of design is showed by Open Graphics Library.This paper realizes the automatic generation of space grid structure.