Static And Stability Analysis Of Inverted Catenary Surface Reticulated Shells

Single-layer reticulated shell structures have a wide range of application in practical engineering because of the advantages of simple structure,light weight,reasonable force,beautiful appearance,good economic performance,etc.However,the stability of a single-layer reticulated shell structure is the main problem in designing due to its large span and thin thickness.The surfaces of reticulated shell structures are in many forms,such as cylindrical,spherical,hyperbolic paraboloid,etc.In this paper,a new curved reticulated shell structure,an inverted catenary surface reticulated shell which is obtained by rotating around its axis of symmetry with the catenary line as the generatrix is taken as the object,and its static performance and stability are analyzed in detail by setting up models with the finite element software ANSYS.Firstly,the ultimate bearing capacity of the inverted catenary surface reticulated shells and spherical reticulated shells with different grid types was compared,and the bidirectional monoclinic rod schwedler reticulated shell is proved to be a relatiely reasonable grid form.Secondly,a detailed comparative analysis of the static performance and stability of the inverted catenary surface reticulated shell structure and the spherical reticulated shell structure was made,and it is concluded that the inverted catenary surface reticulated shell structure is superior to the spherical reticulated shell structure.Thirdly,a large-scale parametric analysis was carried out on the inverted catenary surface reticulated shells structure.The effects of parameters such as the member sectional dimension,the rise-span ratio,the initial geometric imperfection,unsymmetrical distribution of loads,the support constrained form and the ways of selecting knot on the geometric nonlinear stability of the structures were studied.Finally,on the basis of geometrical nonlinearity,the material nonlinearity was introduced,and the influence of the material nonlinearity on the stability of the inverted catenary surface reticulated shell structure was studied.Several common failure modes of the perfect structure and defective structure were studied,and the whole process of plasticity development was tracked and analyzed.In addition,the effects of initial geometric imperfection and unsymmetrical distribution of loads on the elasto-plasticity ultimate loads of the shells were analyzed.The research of this paper can provide some theoretical guidance and reference for future engineering application of such structure.