A New Algorithm for Size Optimization of the Truss Structures with Buckling Constraint using Finite Element Method

• Published in: IOP conference series. Materials Science and Engineering Vol. 661; no. 1; pp. 12041 - 12050
• Main Authors: Bich Quyen, Vu Thi, Khanh, Cao Quoc, Thuy Van, Tran Thi, Khoa, Dao Ngoc, Truc, Thai Phuong
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01.11.2019
• Subjects: Algorithms; Buckling; Compressive strength; Correlation coefficients; Finite element analysis; Finite element method; Genetic algorithms; Internal forces; Iterative algorithms; Mathematical analysis; Optimization; Trusses; Weight
• ISSN: 1757-8981; 1757-899X
• DOI: 10.1088/1757-899X/661/1/012041

This paper proposed a way to solve the problem of the optimum size of the truss, taking into account the local buckling constraint of compression elements of the truss. The consideration of dynamic constraint for buckling increases the complexity of the iterative algorithm to solve the truss optimization problem, because the dynamic constraint expresses condition involving the cross-sectional variable. The author has established an iterative algorithm to optimize trusses with stresses constraints (under strength conditions for tensile elements, buckling conditions for compression elements) and displacements. The iterative algorithm is established based on the correlation coefficients of internal forces between elements. The constraints of the problem are established on the basis of the results of internal forces, displacement and governing equation by finite element method. Based on the established algorithm, the authors had written the program to solve the optimization problem of plane trusses with 10 and 17 elements, spreading the space trusses of 25 elements. Comparing the results of weight optimization of the trusses by the proposed method of this paper with the results based on genetic algorithms, there is no significant difference, especially when increasing the number of elements, the weight of the truss calculated by the author's method is significantly smaller.