  In this paper we present a novel method to overcome membrane locking of thin
shells. An interpolation operator into the so-called Regge finite element space
is inserted in the membrane energy term to weaken the implicitly given kernel
constraints. The number of constraints is asymptotically halved on triangular
meshes compared to reduced integration techniques. Provided the interpolant,
this approach can be incorporated easily into any shell element. The
performance of the proposed method is demonstrated by means of several
benchmark examples.
