Multiple constraints in structural optimization

Abstract

SUMMARYThis paper considers the problem of solving the optimality criteria equations for a truss structure. A unique Newton-Raphson method for optimizing redundant structures subject to multiple constraints on displacement and member sizes is presented. Both equality and inequality constraints are considered. The characteristics of this approach along with least squares and recursive techniques for the solution of the non-linear optimality criteria equations are examined numerically for several sample problems. This new formulation offers the advantages of a reduction in the number of dependent variables, ease of incorporation of various types of constraints, and very rapid convergence.

Strength Analysis of Steel Bridge for Large Structure Shift Transportation

“…When the finite element method was used, the size of wharf model could not be taken to be infinite, only when the model try to get a large size model, but if the size was too large, it would greatly increase the computational workload, so the structure of the pier was simplified to improve efficiency in the process of finite element analysis if the results of the wharf strength were not affected [5]. C30 concrete was constructed the wharf, SOLID65 unit was used to simulate the caisson structure; the caissons structure were 200mm thin concrete, each small box size of caissons was 4500mm × 3600mm, which filled with stone, SOLID65 simulate unit was used in the ANSYS; the steel bridge was connected together by 10 beams of HEB200 [6]. In order to improve computational efficiency, the steel bridge was simplified shell element of SHELL63, which real constant value was assigned to the thickness of the flanged beam, the material of flanged beam was Q345.…”

Minimum cost design of RC beams using DCOC Part I: Beams with freely-varying cross-sections

“…The optimum design of structural members and assemblies have been obtained using mathematical programming methods (direct methods) (Haug and Arora 1979;Kanagasundaram and Karihaloo 1990;Karihaloo 1993;Kanagasundaram 1986, 1988;Kirsch 1981), and methods based on optimality criteria (indirect methods) (Adamu et al 1994;Chou 1977;Fleury 1979;Gellatly et al 1978;Haug and Arora 1979;Khot 1981;Khot el al. 1978;Kitsch 1981;Moharrami and Grierson 1993;l~ozvany 1989;Rozvany el al.…”