Geometric Configuration And Mechanical Performance Analysis Of Reciprocal Structure

Reciprocal structure is one kind of spatial structure,which is made of beams that support each other along their span.Reciprocal structure has beautiful mesh pattems which is loved by the architect who build it in a good way to makes people can enjoy it.This kind of connection between two members avoids the intersection among too many members that intersect to a single point and also make it easy to connect two members together,which reduces the connection complexity.Although reciprocal structure has the advantges,there still are two major problems of designing reciprocal structure.Members are connected by overlapping which has a strong relationship with every member of reciprocal structures.This kind of restriction brings a lot of difficulties to positioning members of reciprocal strutures which makes geometric configuration of reciprocal structure a major research topic in recent years.Besides that,there is bending moment in all the members,which can't transfer the force in an efficient way.This kind of force transferring makes machinic performance improvement a necessary topic to solve.This topic affects the application of reciprocal structure.This paper has done some research about the above problems of reciprocal structure and developed a form finding method,developed several functional Grasshopper plugins and done some analysis about its machnical properties.Specific content includes:(1)Based on the construction process of reciprocal structures,this paper proposes two methods to generate the original mesh of structure which are mesh-rotation method and unit transition method.This paper define a relation judgment method to judge weather one beam is overlapped to another.Finally this paper introduced Circular overlapping method which achieve “adaptive” form finding of reciprocal structure.The example analysis shows that this method is simple and efficient in comparison with other method.(2)By using C# language,this paper developed several plug-ins based on circular overlapping method of reciprocal structure for Grasshopper.This paper developed plugins like projection,mesh generating,line picking-up,adding radius,Circular overlapping,data combining,boundary division,boundary position changing,and Ansys conversion.Through the combination of the plug-ins above,different design goals can be achieved,and form finding of complex reciprocal structure can also be achieved.(3)This paper discusses the finite element simulation model of reciprocal structure in Ansys,and analyses the mechanic performace of typical reciprocal structure.Base on the result above,this paper also do the mechanic analysis on the span ratio,section type of beam and type of mesh to give advice on how to improve its performance.The results shows that the mechanical performance of the reciprocal structure can be improved by using the large span ratio,selectiong the cross-section of the members which are more open and easy to be connected and using dense mesh.