An edge-based smoothed triangle element for non-linear explicit dynamic analysis of shells

The paper presents an edge-based smoothed triangular element (EST) for nonlinear analysis of shell structures using an explicit dynamic formulation. In order to improve the accuracy and the convergence of the shell element without additional parameters, the gradient smoothing operation is performed to the strain rates in the smoothing domains associated with the edges of triangular elements. An edge coordinate system is defined local on the edges of the triangular element for the strain smoothing operation. The material nonlinearities for the dynamic solution are treated by using the updated Lagrangian description and an elastic-plastic constitutive law. The shear strains in the element formulation are approximated using the discrete shear gap method to mitigate the shear locking, and this element can be applicable for both thin shells and thick shells. Numerical results for elastic and elastic-plastic problems show the effectiveness and efficiency of the proposed shell element.