Partial Double Reticulated Shell Shape Optimization And Stability Analysis Of Pyramidal System

Reticulated shells are widely used in recent years, a large sports/arts venues, waiting/waiting halls, shopping malls and other public buildings in the city’s iconic modern structures. Shell has a large network covering space, different forms of structure can provide different architectural style and use of functions, thus becoming a cause for concern and has a structure in the form of development potential.Pyramidal system of partial double reticulated shells in six typical reticulated shells, based on the rod according to certain rules to strengthen the structure formed by connecting nodes. Pyramidal system of partial double spherical shell in the overall network capacity and ability to resist deformation when compared with single-layer reticulated shells has improved greatly, suitable for medium and large span structures. But rods constitute more complex form such structures to explore aspects of shape optimization is not perfect. Pyramidal system and localized double reticulated shell structure when applied to large-span buildings, its stability problems have become increasingly prominent, the key structural design.The main contents:1. Application of ANSYS of APDL programming language, developed a pyramid system of reticulated shells parametric design macros given to the four corners of the triangular cone and the cone is the basic unit of six pyramidal system reticulated shell structure parametric design and modeling methods; analysis of the shell structure of these networks and nodes connecting rod distribution law, the application must enter the macro from the macro-structure of the geometric parameters required to generate net shell model. The relationship between these reticulated shell macro-and micro-geometry geometric parameters, and the corresponding mathematical expressions provide a meaningful reference for the actual project.2. The pyramidal system spherical reticulated shell are analyzed by using ANSYS software, research the reticulated shell under uniformly distributed load, the maximum displacement and the stress position and distribution, to lay a foundation for the further optimization design.3. In the FORTRAN environment, the pyramidal system of spherical shell shape optimization design program based on discrete variables, diagonal cone system spherical reticulated shell for the shape optimization design. In most provinces the amount of structural steel for the optimization objectives, consider locality constraints and global constraints, the analysis reached a different span ratio, different network shell type, the amount of steel rings to repeat its regional scores and the number of turns by radial nodes the impact of changes in laws and study the optimal combination of law reticulated shells pyramid system design parameters, namely, the optimal number of grids, to provide the actual network shell works of reference.4. Buckling stability analysis of the pyramidal system spherical reticulated shell is optimized by using ANSYS software. The buckling analysis and nonlinear analysis considering geometric imperfections. The Kiewitt reticulated spherical shell with different rise to span ratio (1/3～1/7) of buckling modal analysis, and on this basis a whole process with geometric nonlinear structural defect analysis through load-displacement curves were analyzed nonlinear behavior of each node, and span ratio effect on the nonlinear behavior of the actual project has come to refer to meaningful conclusions.