Normal-normal continuous symmetric stress approximation in three-dimensional linear elasticity
Carsten Carstensen and Norbert Heuer
Numer. Math. 158 (4), 1451–1472, 2026.
We present a conforming setting for a mixed formulation of linear elasticity with
symmetric stress that has normal-normal continuous components across faces of tetrahedral meshes.
We provide a stress element for this formulation with 30 degrees of freedom that correspond
to standard boundary conditions. The resulting scheme converges quasi-optimally and is
locking free. Numerical experiments illustrate the performance.