Nonlinear Buckling Of Inverted Catenary Single-layer Cylindrical Reticulated Shells

Cylindrical reticulated shells have a wide range of application in the reticulatedshells, which have the advantages of simple structure, reasonable force, beautifulshape, good economic effects, ect. Single-layer reticulated shells taking membraneforce as the main force characteristic have superior mechanical performance, but thisstructure is very likely to generate instable failure because of superior span and thinthickness, and structure instability become the main failure reason of this kind ofstructure. Therefore, the stability problem of the single-layer cylindrical reticulatedshells is particularly outstangding in cylindrical reticulated shells, the stabilityanalysis of which is very necessary.The stability performance of common single-layer cylindrical latticed shells hasbeen relatively matured, which alignment in the form of circular arch, but the studieson the structures of single-layer cylindrical reticulated shell in the form of other archalignment are very little. According to the unique mechanical performance of catenaryarch, taking catenary arch as the horizontal alignment of the cylindrical reticulatedshells can form a new cylindrical reticulated shell-inverted catenary cylindricalreticulated shells, the nonlinear static stability of which was studied deeply andsystematically in this paper by finite element software of ANSYS.Firstly, according to the inverted catenary single-layer cylindrical reticulatedshells with arch alignment in the form of catenary, the stability of three common gridconfigurations of which were analyzed and compared in this paper, a reasonable gridlayout was determined; and then its overall stability and static performance werefurther compared with single-layer cylindrical reticulated shells to obtain theimprovement of its stiffness and bearing capacity.Secondly, by analyzing the large-scale parameters, the geometric nonlinearstability of inverted catenary single-layer cylindrical reticulated shells was studied,including the effect of length-span ratio, raise-span ratio, member sectional dimension,initial geometric imperfection and unsymmetrical distribution of loads on the ultimateloads of the inverted catenary single-layer cylindrical reticulated shells, and then onthis basis the scientific regression analysis of the large data was done and the fittingformula for the limit loads of the inverted catenary single-layer cylindrical reticulatedshells were provided.Finally, on the base of considering the geometric nonlinearity of the reticulated shells, further considering material nonlinearity factor, a series of double nonlinearanalysis of the inverted catenary single-layer cylindrical reticulated shells werecarried out, the buckling modes and the whole process of plasticity development ofthe structures were collected, the effect of material nonlinearities, initial geometricimperfections and unsymmetrical distribution of loads on the elasto-plasticityultimate loads of the shells were analyzed, the elastic-plastic stability of this structurewere studied comprehensively and systematically.The research in this paper can provide theoretical basis and reference for thepractical engineering application of such structure.