STUDIES OF STRESS-CONCENTRATION BY USING SPECIAL HYBRID STRESS ELEMENTS

The stresses around rectangular holes of rounded corners and rounded n otches are analysed by using the combination of three kinds of three-d imensional special hybrid stress finite elements. One kind of three-di mensional hybrid stress finite element with a traction-free inclined s urface has been developed here based on an extended Hellinger-Reissner principle by a rational approach. Other two kinds of 12-node three-di mensional hybrid stress elements with a traction-free cylindrical surf ace and a traction-free perpendicular surface, respectively, were deri ved based on the Hellinger-Reissner principle. Examples have indicated that the combination of these special solid elements is far superior in predicting the stress concentration factors, the distributions of c ircumferential stresses and normal stresses for solids with holes and notches. (C) 1997 by John Wiley & Sons, Ltd.