A simple assumed strain method for enhancing the accuracy of the cubic triangular C degree plate bending element

Abstract

The conventional cubic triangular Mindlin/Reissner plate bending element, DISP10, is in general too stiff. To reduce the element stiffness, three of the strain sampling points are shifted from the integration stations to the element corners so as to reduce the number of shear constraints in the global level. The strain field is then obtained by interpolation. In this way, the constraint ratio of the element increases from 1.125 to 1.5 which is exactly equal to a postulated optimal value. However, the element does not appear to be more accurate than its conventional counterpart. While keeping the constraint ratio and interpolation pivots unchanged, two different ways of refining the sampled strains at the element corners are attempted and the pertinent elements are consistently more accurate than DISP10