Parametric Modeling And Shape Optimization Of Six Typical Double Reticulated Dome

Reticulated dome is a bar grid according to certain rules, according to the dome structure layout space framework, which combines the feature of the truss and dome, with reasonable force, covering the span, and can provide a variety of beautiful styling, which is a domestic and international popular concern, there are broad prospects for development of spatial structure. However, there are a lot of practice proved that the traditional design methods are able to ensure the safety and durability of the structure, but the mechanical properties of materials of the entire structure can not be fully utilized and the overall cost will be high, it is necessary to optimize the design of the structure.The main content of the thesis:1, On the platform of finite element software ANSYS, using APDL language of its own parametric modeling and the static structural analysisand of the six typical double-layer reticulated dome structures. Users only need input vector (F), span (S), number of copies to the repeat region of the ring (Kn), the radial note number of turns (Nx), double thickness (T) of these macro-geometry control parameters to generate the required models, laying the foundation for the structural analysis and design optimization2, According to the features of the double-layer spherical reticulated, here proposed shape optimization of the two algorithms of dome bar section size (A), node volume (V), number of copies to the repeat region of the ring (Kn), the radial note number of turns (Nx), double thickness (T) as design variables.lt reference to the relevant specification, it is the total weight of the lightest double-layer spherical reticulated dome steel as the objective function, and the strength, stiffness, geometry, and the rod stability as the condition of constraints, establishing mathematical model of shape optimization of double-layer reticulated dome structures. It is based on the shape of the proposed optimization of two algorithms in the paper, shape optimization program compiled in the FORTRAN environment, this program can drive the structure of finite element software ANSYS static analysis in the background, it is to achieve to call each other between the structural analysis and shape optimization, providing a convenient for static analysis-calculation and shape optimization of the reality engineering.3, Selecting the small span (30m,40m,50m), medium span (60m,70m,80m), large span (90m,100m,110m,120m), rise-to-span ratios1/7,1/6,1/5,1/4,1/3, and the thickness of lm, it’s done a total of300shape optimization example. Analyzed the law of steel consumption with the span and rise-to-span ratios changes of the same network dome, there have been the conclusion:a small span steel consumption with the vector cross-be increase than the increase in the span, and large-span steel consumption with the rise-to-span ratios first decreases then increases to rise-to-span ratios of1/5or1/4steel consumption to a minimum; Analyzed in the same span and the double layer thickness of different dome types of steel consumption with the rise-to-span ratios variation, concluded that:The most economical steel consumption of the small span is the Lamella or t three way grid, medium plan is geodesic, and large span is k-8of kiewitt. It provides the theoretical basis for Engineering practice.