Perturbation mapping method for sensitivity analysis of three-dimensional cracks near a free surface

✍ Scribed by Yonglin Xu; Ahmed K. Noor

• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 197 KB
• Volume: 189
• Category: Article
• ISSN: 0045-7825
• DOI: 10.1016/s0045-7825(99)00314-x

✦ Synopsis

A perturbation mapping method and a computational procedure are presented for evaluating the sensitivity coecients of the stress intensity factors for three-dimensional planar cracks near a free surface. The boundary integral equations for evaluating the sensitivity coecient are solved by using the boundary element method. Each of the geometric parameters that aect the stress intensity factor (such as, crack orientation, distance from the free surface, and crack shape parameters) is given a perturbation which de®nes a mapping between the original and perturbed coordinate systems, from which the sensitivity coecients are derived. The sensitivity coecients obtained by the perturbation mapping method are validated by comparing them with those obtained by the ®nite dierence method. Numerical results for penny-shaped and elliptical cracks are presented showing the variation of the sensitivity coecients with various geometric and material parameters.