A triangular thin shell element for the linear analysis of stiffened composite structures

A three node flat shell element with six engineering displacement degree-of-freedom at each node is developed. The basic formulation allows for the arbitrary location of the reference surface in which the membrane forces and bending moments are fully coupled. The well-known, highly accurate, DKT bending element is combined with a higher order membrane element in order to obtain a consistent formulation. The higher order membrane behavior is obtained by the introduction of three additional normal rotational degree-of-freedom. This report presents a summary of the theoretical steps involved in the development of the element. The accuracy of the element is illustrated by the solution of several standard problems and a comparison of results with other thin shell elements. (jes)