Layout optimization of long-span structures subject to self-weight and multiple load-cases

• Published in: Structural and multidisciplinary optimization Vol. 65; no. 7
• Main Authors: Fairclough, Helen E., Gilbert, Matthew
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.07.2022; Springer Nature B.V
• Subjects: 14th World Congress of Structural and Multidisciplinary Optimization; Bending stresses; Computational Mathematics and Numerical Analysis; Engineering; Engineering Design; Hemp; Integer programming; Layouts; Mathematical programming; Methods; Numerical methods; Optimization; Research Paper; Structural design; Theoretical and Applied Mechanics; Equal stress catenary; Long spans; Layout optimization; Self-weight; Truss topology optimization
• ISSN: 1615-147X; 1615-1488
• DOI: 10.1007/s00158-022-03242-9

Layout optimization provides a powerful means of identifying materially efficient structures. It has the potential to be particularly valuable when long-span structures are involved, since self-weight represents a significant proportion of the overall loading. However, previously proposed numerical layout optimization methods neglect or make non-conservative approximations in their modelling of self-weight and/or multiple load-cases. Combining these effects presents challenges that are not encountered when they are considered separately. In this paper, three formulations are presented to address this. One formulation makes use of equal stress catenary elements, whilst the other two make use of elements with bending resistance. Strengths and weaknesses of each formulation are discussed. Finally, an approach that combines formulations is proposed to more closely model real-world behaviour and to reduce computational expense. The efficacy of this approach is demonstrated through application to a number of 2D- and 3D-structural design problems.