Developments in the residual strength based shape optimisation

R. Das, R. Jones

Research output: Chapter in Book/Report/Conference proceedingConference PaperOther

Abstract

The paper presents a methodology for shape optimisation of structures with fracture strength as the design objective. There have been limited applications of durability based optimisation to realistic structures. To overcome this, we present a 3D biological algorithm that uses fracture parameters as the design criteria. Damage tolerance optimisation is illustrated via the problem of optimal design of 'a through-hole in a rectangular block under biaxial loading'. A wide range of 3D flaws were considered and it was found that the optimum hole shapes were approximately elliptical with the aspect ratios being dependent on crack sizes, structural geometry and boundary conditions. It has been shown that the fracture strength optimised shape can be different from the corresponding stress optimised solution. This emphasises the need to explicitly consider fracture strength as the design objective. In all cases, a significant reduction in the maximum stress intensity factor was achieved with the generation of a 'near uniform' fracture critical surface. The design space near the 'optimal' region was found to be relatively flat. This is beneficial as a significant structural performance enhancement can be achieved without precise identification of the local/global optimum solution.

Original languageEnglish
Title of host publication4th Australasian Congress on Applied Mechanics, ACAM 2005
Pages705-710
Number of pages6
Publication statusPublished - 1 Dec 2005
EventAustralasian Congress on Applied Mechanics 2005 - Melbourne, Australia
Duration: 16 Feb 200518 Feb 2005
Conference number: 4th

Publication series

Name4th Australasian Congress on Applied Mechanics, ACAM 2005

Conference

ConferenceAustralasian Congress on Applied Mechanics 2005
Abbreviated titleACAM 2005
CountryAustralia
CityMelbourne
Period16/02/0518/02/05

Keywords

  • Damage tolerance
  • Finite element method
  • Fracture strength
  • Stress intensity factor
  • Structural optimisation

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