Generalized conforming curved rectangular shallow shell element with in-plane rotational degrees of freedom

The introduction of rotation degrees of freedom in the shallow shell element can increase the order of the interpolation functions for displacement field, improve the calculation accuracy, and thus significantly improve the performance of element without introducing additional nodes. Since generalized displacement field is introduced into the element, the scope of solution is extended significantly. The present element demonstrates attractive merits, such as high precision and less sensitivity to geometric distortion. In this paper a generalized conforming curved rectangular shell element GRC-S24 with twenty-four degrees of freedom is presented through adding in-plane rotational degrees of freedom. In the derivation of the stiffness matrix of the shell element, the displacement functions of the generalized conforming plate bending element RGC-12 and that of the membrane element with vertex rigid rotational freedoms-were used to describe the normal and the tangential displacement, respectively. Furthermore add a generalized bubble displacement on that base, and then construct another generalized conforming curved rectangular shell element GRC-S24M which with higher precise. Numerical analysis was conducted to validate the accuracy and convergence of these two elements.