A triangular six-node shell element

We present a triangular six-node shell element that represents an important improvement over a recently published element [1]. The shell element is formulated, like the original element, using the MITC procedure. The element has the attributes to be spatially isotropic, to pass the membrane and bending patch tests, to contain no spurious zero energy mode, and is formulated without an artificial constant. In particular, the improved element does not show the instability sometimes observed with the earlier published element. We give the convergence behavior of the element in discriminating membrane- and bending-dominated benchmark problems. These tests show the effectiveness of the element.