“…To overcome the shear locking difficulty and derive 'locking-free' or robust plate bending elements that are valid for the analysis of thick and thin plates, significant efforts are devoted to the development of simple and efficient triangular and quadrilateral finite elements in the past few decades. The most common approach is to modify the variational formulation with some reduction operator so as to weaken the Kirchhoff constraint (see [2,3,4,5,6,7,8,9,10,11,12,15,17,19,20,21,22,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38] and the references therein).…”