Applied Mathematics and Mechanics

, Volume 24, Issue 12, pp 1466–1474

Lower bound limit analysis of three-dimensional elastoplastic structures by boundary element method

• Liu Ying-hua
• Zhang Xiao-feng
• Cen Zhang-zhi
Article

Abstract

Based on the lower bound theorem of limit analysis, a solution procedure for limit analysis of three-dimensional elastoplastic structures was established using conventional boundary element method (BEM). The elastic stress field for lower bound limit analysis was computed directly by three-dimensional boundary element method (3-D BEM). The self-equilibrium stress field was constructed by the linear combination of several self-equilibrium “basis vectors” which can be computed by elastic-plastic incremental iteration of 3-D BEM analysis. The lower bound limit analysis problem was finally reduced to a series of nonlinear programming sub-problems with relatively few optimal variables. The complex method was used to solve the nonlinear programming sub-problems. The numerical results show that the present solution procedure has good accuracy and high efficiency.

Key words

BEM lower bound limit analysis self-equilibrium stress field nonlinear programming complex method

O344.5

74L10 74S15

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© Editorial Committee of Applied Mathematics and Mechanics 2003

Authors and Affiliations

• Liu Ying-hua
• 1
• Zhang Xiao-feng
• 1
• Cen Zhang-zhi
• 1
1. 1.Department of Engineering MechanicsTsinghua UniversityBeijingP.R. China