An improved solid-shell element based on the computational condensation technique

Aiming at improving the result accuracy and the computation efficiency for numerical simulation, an improved solid-shell element with computational condensation technique is proposed in this paper. To ameliorate the result accuracy, seven modified parameters based on the enhanced assumed strain method are included in the improved solid-shell element's strain expression to eliminate the locking problem, while extra control force is supplemented to restrain the hourglass mode. Extra degree of freedom is accordingly involved by this modification, which will consume additional time and storage during the integration steps. To solve these problems, a computational technique based on system variation formula is proposed to simplify the condensation of element's degree of freedom. By combining the improved solid-shell element with computational condensation technique, the simulation of large-scale shell structure can be implemented accurately and efficiently. Three numerical examples of geometrical nonlinearity are given to check the performance of improved solid-shell element with computational condensation technique. Compared with other existing elements, it is shown that the improved solid-shell element can give more accurate results and improve the efficiency by using computational condensation technique. Besides, the improved solid-shell element possesses good compatibility in couple modeling with other existing elements.