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arXiv · 2305.00150

A locking-free mixed enriched Galerkin method of arbitrary order for linear elasticity using the stress-displacement formulation

Zhongshu Zhao·Hui Peng·Qilong Zhai·Qian Zhang
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Abstract

In this paper, we develop an arbitrary-order locking-free enriched Galerkin method for the linear elasticity problem using the stress-displacement formulation in both two and three dimensions. The method is based on the mixed discontinuous Galerkin method in [30], but with a different stress approximation space that enriches the arbitrary order continuous Galerkin space with some piecewise symmetric-matrix valued polynomials. We prove that the method is well-posed and provide a parameter-robust error estimate, which confirms the locking-free property of the EG method. We present some numerical examples in two and three dimensions to demonstrate the effectiveness of the proposed method.

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Zhongshu Zhao, Hui Peng, Qilong Zhai, Qian Zhang. 2023-04-29. A locking-free mixed enriched Galerkin method of arbitrary order for linear elasticity using the stress-displacement formulation. https://arxiv.org/abs/2305.00150

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