An implementation of the ground structure method considering buckling and nodal instabilities

The ground structure method is used to find an optimal solution for the layout optimization problem. The problem domain is discretized with a union of highly connected members, which is called a ground structure. The objective typically is to minimize the total volume of material while satisfying nodal equilibrium constraint and predefined stress limits (plastic formulation). However, such approach may lead to very slender members and unstable nodes that might cause instability issues. This thesis presents the implementation of the ground structure method involving instability consideration. The plastic formulation is implemented considering buckling constraint and nodal instability constraint either in isolation or in combination. The Euler buckling criteria is taken as the buckling constraint in the implementation with local instability consideration. The nominal lateral force method is used in the implementation involving nodal instability consideration. Moreover, the efficiency of the nonlinear programming is addressed. Several numerical examples are presented to illustrate the features of the implementation.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Civil Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Zhao, Tuo

Contributors dc:contributor

• Paulino, Glaucio

• Ground structure
• Topology optimization
• Buckling
• Nodal instability

Statement dc:rights

• Copyright 2014 Tuo Zhao

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/73030

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/73030