PSO-Based Approach for Buckling Analysis of Shell Structures with Geometric Imperfections

Lisheng Luo,Wenyuan He,Xiaofeng Zhang

doi:10.1155/2019/4073919

Lisheng Luo, Wenyuan He + Show 1 more

Open Access

https://doi.org/10.1155/2019/4073919

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Abstract

The buckling loads of shell structures are sensitive to initial geometric imperfections. Conventional methods used to model geometric imperfections cannot determine the accuracy of buckling loads with high computational efficiency. A new computational approach based on particle swarm optimization (PSO) is proposed to obtain the lower bound of the buckling load of shell structures with geometric imperfections. The proposed approach assumes a nodal geometric position using uncertain parameters. The buckling loads of the shell structures are then optimized using the PSO-based approach. Both academic and practical numerical examples have been thoroughly investigated. Thus, the applicability and accuracy of the proposed method is critically validated.

Highlights

Shell structures are widely used in large-span public construction owing to its novel shape, low dead weight, and excellent mechanical behavior
Five unstiffened shells are tested in [25]. e measured imperfection approach, single-perturbation load approach (SPLA), worst multiple perturbation load approach (WMPLA), and combined approach for measured imperfections and superimposed radial point load imperfections are compared with test results, and the results show that the knockdown factors by the WMPLA and the combined approach are similar to one another and very close to the test results
To realize the purpose of the limit-state analysis of structural buckling, this paper presents a novel particle swarm optimization- (PSO-) based computational scheme to search the worst case imperfect shape of shell structures

Summary

Introduction

Shell structures are widely used in large-span public construction owing to its novel shape, low dead weight, and excellent mechanical behavior. E measured imperfection approach, single-perturbation load approach (SPLA), WMPLA, and combined approach for measured imperfections and superimposed radial point load imperfections are compared with test results, and the results show that the knockdown factors by the WMPLA and the combined approach are similar to one another and very close to the test results Such diverse approaches have successfully been proposed, some of which are even used in practical engineering applications, a key problem, i.e., the worst case imperfect shape of a nodal geometric position, has not yet been solved. To realize the purpose of the limit-state analysis of structural buckling, this paper presents a novel particle swarm optimization- (PSO-) based computational scheme to search the worst case imperfect shape of shell structures.

Problem Statement

PSO-Based Approach for Buckling Analysis

Numerical Investigations

Methods