Quasi-optimal adaptive hybridized mixed finite element methods for linear elasticity
For the planar elasticity equation, we prove the uniform convergence and optimality of an adaptive mixed method using the hybridized mixed finite element in [Numer. Math., 141 (2019), pp. 569-604] proposed by Gong, Wu, and Xu. The main ingredients of the proof consist of the discrete reliability and quasi-orthogonality, which are both derived using a discrete approximation result. Compared with Arnold--Winther and Hu--Zhang mixed elements, the adaptive hybridized mixed method yields nested discrete stress spaces so that the rigorous quasi-optimal convergence rate can be established.
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