Original paper(Vol.48 No.9 pp.1017)

Effect of edge shape on static and fatigue failure of steel-rubber laminated structure in shear with compression

Okubo Kazuya; Lee Yi Chang; Kuroda Susumu; Fujii Toru

Abstract:The static shear strength and fatigue life were measured at room temperature in transversal compression. The geometory of testing specimen was the double lap joint type, laminated by rubber and steel plate having rounded or chambered edge.
A significant difference in observed strength was found between the specimens having rounded and chambered edges. The static strength of the rounded (R) or chambered (C) edge specimen increased about 10% with that of the non-curved edge (FL) specimens. The non-dimensional shape parameter (Se) was introduced to evaluate the edge shape effect. This parameter is defined by the edge dimension divided by the thickness of the laminated rubber. Internal stress distribution was solved by the nonlinear FEM analysis. The stress concentration point around the edge coincided with the initiation point of the failure observed by microscope camera. The fatigue life of rounded or chambered edge specimens (R,C specimen) was nearly equal or longer than that of non-curved edge specimens. The fatigue life, however, little increases with an increase of the dimensions of R at the edge.

Key Words:rubber, laminate, double lap joint, static strength, fatigue life, compression, rounded edge, chambered edge, FEM