Selective Element Domain Interpolation Technique for Assumed Rotations and Shear Strains in Polygonal Finite Element Thick/thin Plate Analysis

This paper proposes a novel selective element domain interpolation technique, named SI-ARS-Poly, to develop a high-performance spatially isotropic polygonal element for thick/thin plate analysis. In the SI-ARS-Poly approach, nodal assumed rotations on the element boundaries are directly computed at the mid-nodes of element edges by linearly approximating based on the first-order one-dimensional shape functions. Then, a selective interpolation scheme is applied to approximate the nodal assumed rotations and shear strains on element boundaries into the element domain using piecewise-linear-based first- and second-order shape functions. The proposed method passes spatially isotropic, zero-energy mode, and bending path tests, and exhibits a high performance with uniform and excellent convergent rates compared to existing methods.