Multi-objective Morphological Optimization And Mechanical Properties Of Umbrella Single Layer Spatial Grid Structure

The form of free-form surface space grid structure is mostly used in public buildings.The umbrella-shaped single-storey space grid structure is one of the freeform surface space grid structures,also known as the "trumpet pattern" structure,which is often used in combination with the triangular grid.Structural morphology explores the relationship between structural form and structural performance as a whole.In the practical application of umbrella single layer spatial grid structure,the form of the surface is usually given,which needs to be used to design the load-bearing components,and the overall form of the structure is generally only allowed to be slightly modified on the basis of the given form of the surface.When optimizing the structural form,it is necessary to improve the structural performance on the premise that the structural form changes little.In view of the above problems,this paper explores the following aspects:1)Complete the modeling of umbrella-shaped single-layer spatial grid structureBased on Rrhinoceros platform,NURBS(Non-uniform Rational B-spline)technology was used to model the surface.Different forms of umbrella surfaces were constructed and splice,and the splice of different curvature surfaces was smoothened by control point processing,so as to ensure the smooth progress of the subsequent discretization of surfaces.The diamond segmentation method and the lever length method were used to discretize the surface(meshing).The performance differences of meshing obtained by different meshing methods were compared,the adaptability of different meshing methods was explored,and design suggestions were given.2)Analyze the results of multi-objective morphological optimization of structures with different optimization objective combinationsIn this paper,the multi-objective morphological optimization of umbrella single layer spatial grid structure was explored,and the height of all nodes of the grid was taken as the optimization variable,so as to adjust the grid shape during the optimization process.SH-MOEA(Hybrid Optimization Algorithm Based on Sensitivity)was selected as the optimization algorithm.Different optimization objective combinations were selected to carry out multi-objective shape optimization of the structure,and the optimization effect of the structure under different optimization objective combinations was analyzed.The nonlinear finite element analysis is carried out to calculate the ultimate bearing capacity of the optimization results of multi-objective shape optimization,and the design suggestions of multiobjective shape optimization are given to guide the application of practical engineering.3)The multi-objective shape optimization and analysis of an umbrella grid structure was carried outChoosing a using umbrella monolayer space grid structure in the form of practical engineering modeling,respectively,to the actual engineering structure model and the meshing method in this paper the configuration structure model for multi-objective optimization,and analysis of the difference of structure performance before and after optimization,to evaluate the application of this optimization method,and design Suggestions are given.In this paper,the modeling of the umbrella single layer spatial mesh structure is completed,and the multi-objective morphological optimization of the umbrella mesh structure is realized based on the hybrid optimization algorithm.The design suggestions are given by analyzing the structural performance before and after the optimization.Finally,the application analysis of an umbrella mesh structure is carried out by using the optimization method in this paper.