  The first super-convergent hybridisable discontinuous Galerkin (HDG) method
for linear elastic problems capable of using the same degree of approximation
for both the primal and mixed variables is presented. The key feature of the
method is the strong imposition of the symmetry of the stress tensor by means
of the well-known and extensively used Voigt notation, circumventing the use of
complex mathematical concepts to enforce the symmetry of the stress tensor
either weakly or strongly. A novel procedure to construct element-by-element a
super-convergent post-processed displacement is proposed. Contrary to other HDG
formulations, the methodology proposed here is able to produce a
super-convergent displacement field for low order approximations. The resulting
method is robust and locking-free in the nearly-incompressible limit. An
extensive set of numerical examples is utilised to provide evidence of the
optimality of the method and its super-convergent properties in two and three
dimensions and for different element types.
