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IJEMS Vol.14 [2007] >
IJEMS Vol.14(1) [February 2007] >
| Title: | A modified quarter point element for fracture analysis of cracks |
| Authors: | Paul, Sayantan
Rao, B N |
| Issue Date: | Feb-2007 |
| Publisher: | CSIR |
| IPC Code: | G01N |
| Abstract: | A modification to the quarter-point crack tip element for the computation of stress intensity factors in cracked plates subjected to mixed mode loading is presented. The standard quarter-point singular element is modified such that the near tip crack opening displacement satisfies a known constraint; the coefficient of the term in William’s expression which is a linear function of the distance to the tip must vanish in order to have the singularity at the crack tip. Stress intensity factors computed using the modified quarter-point crack tip element in conjunction with the displacement correlation technique gives better results as compared to those obtained by the standard quarter-point element. The technique basically involves the same guidelines as that of the standard quarter-point element, where 6-noded quarter-point elements are adopted to mesh the singular region around the crack tip and 8-noded quadrilateral elements are adopted to mesh rest of the non-singular region. Based on the shape functions of the proposed modified quarter-point crack tip element the equations for computing the crack tip opening displacement and the stress intensity factors are presented taking into account the nodal displacement values of the elements around the crack tip. The results obtained using the modified quarter-point crack tip element are shown to be significantly more accurate than those obtained using the standard quarter-point element for both mode-I and mixed-mode problems. |
| Page(s): | 31-38 |
| ISSN: | 0971-4588 |
| Source: | IJEMS Vol.14(1) [February 2007]
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