Topological Optimization Analysis Of Structure Based On Volume Constraint Model And Reliability

Compared with traditional optimization methods,topology optimization of structures has become the research focus of modern structure optimization with advantages,such as directly optimizing the structure performance,saving optimization design time,and the engineering cost.The deterministic optimization for 2D structures is the main research direction currently.Most of the structures in the project are 3D structures.Besides that,the design parameters,which are waiting to be optimized,maybe random variables with nonnormal distributions.Therefore,it is difficult to conduct deterministic optimization.Because of the above problems,this paper takes the continuous structure topology optimization method,combined with reliability,as the main analysis content.The main work includes:(1)This paper explores the theory development of structure topology optimization and current research in the world.Besides that,by analyzing the existing common problems,this paper proposes a topology optimization design method for 3D structure based on variable density method and reliability theory.(2)This paper expounds on the related principles and modelling methods on structural reliability and topology optimization.The JC method and the variable density method are selected as the reliability modelling method and the topological optimization modelling in this paper.Furthermore,this paper research function interpolation model method and optimization algorithms,which are commonly used in structural topology optimization.SIMP model is used as an interpolation model in variable density method,the optimized solution algorithm conducted based on optimization criterion method,and a suitable sensitivity analysis equation is established in this paper.Also,this paper suggests some reasonable solution to deal with the common topology optimization problems happened in grayscale units,checkerboards,grid dependence,and local extreme values.Using the numerical simulation method,we study the influence of penalty factor,filter function,and floor area ratio on the model.(3)This paper takes the eight-node hexagonal unit as the basic analysis unit,the reliability topology optimization model with 3D continuous structure is established,which takes the structure volume and reliability as the constraint and the softness minimization as the goal.The optimization program also has been written to carry out reliability topology optimization research on the cantilever beams,simple support beams,and ultra-static beams under different operating conditions.Besides that,the results have been compared with the optimization results from traditional topological optimization methods.The results illustrate that the cantilever beam optimization effect is most obvious under the condition that the cloth load is average,with 40% structure volume reduction comparing to the traditional optimization method.Moreover,the structure volume of the cantilever beam is reduced by about 20% under other operating conditions.This paper explores the topology optimization of the cantilever beam with different sizes under the condition of average cloth load.It shows that the structure after the reliability optimization is smaller,lighter weight,more reasonable distribution of rod parts,more reliable structure,easy to construct,lower production costs,and better optimization effect.This means that the method is feasible and reliable,with a more ideal optimization effect,which provides a better method for the optimization of 3D structure topology in projects.