The Analyzing of the Discontinuity Problem by Enriched Interpolation Covers

Document Type : Research Article

Authors

1 Civil Eng. Dep. Shahid Rajaee Teacher Training Univ. Lavizan. Tehran. Iran

2 Phd. Student

Abstract

The cover numerical method is based on unit partitioning, using enrichment functions of various orders, this method increases the accuracy at every point. In this method, unknowns are added to the points of not sufficient accuracy, regarding to the enrichment interpolating functions. The cover method has proved its efficiency in a variety of engineering problems. The Heaviside function models the displacement discontinuity on the crack boundary. Such functions are added to model the coefficient of stress intensity for the tip of the crack. In this paper, the proposed method has been verified by evaluating crack parameters for instances containing fixed fractures. In the end, three numerical instances containing central crack, edge crack and inclined crack with three different cracks are inspected. The comparison of the results from the presented method, with exact solutions and other solutions in the area of linear elasticity, proves the reliability and accuracy of the proposed method.

Keywords


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