ISSN:
0029-5981
Keywords:
stress singularities
;
stress intensity factors
;
FE Model solution convergence
;
Engineering
;
Numerical Methods and Modeling
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Mathematics
,
Technology
Notes:
Enriched 2-D and 3-D finite elements are formulated for analysis of solids having multi-material junction and wedge configurations that create singular stress fields due to the material and/or geometric discontinuities. The order and angular variation of the displacements associated with the singular fields are determined from a separate special finite element eigenanalysis and used in the enrichment process. The use of these numerically determined singular fields allows enriched elements to be developed for complex configurations for which analytical fields are not available. In addition to this added flexibility of application, the current formulation applies to elements that may or may not be in direct contact with the singular point. This allows multiple layers of enriched elements to be used around the singular point and traditional mesh refinement studies to be carried out in the enriched element region. Previous enriched formulations have not provided this important capability. For cases where analytical fields are available, such as cracked solids, the performance of elements developed with the current approach is shown to be equivalent to that obtained using analytically enriched elements. Mesh refinement techniques using enriched elements are described that allow accurate stress distributions and generalized stress intensity factors to be directly determined. The importance of high-order numerical integration, use of multiple layers of enriched elements, and proper choice of the size of the enriched region are demonstrated by comparison to existing solutions for solids with cracks. Application of enriched element modelling to a 2-D bi-material wedge and a 3-D stepped-thickness anisotropic composite laminate is demonstrated. © 1997 John Wiley & Sons, Ltd.
Additional Material:
22 Ill.
Type of Medium:
Electronic Resource
Permalink
