Cleavage Test Considering Frictional Force between Butt Ends

Abstract

The wedged and halved scarf joint, Okkake-tsugi, is one of the Japanese traditional wood joints. In the process of bending failure, a cleavage fracture is observed by friction force at the butt end of the joint. According to the failure, it is supposed that one of the factors determines the yielding of joints. After splitting failure of the butt end, because of increasing displacement and because the assumption of the Navier hypothesis no longer holds, it is necessary to estimate the load at cleavage fracture by friction force at the butt end in order to predict the load-deformation behavior at the joint and the subsequent yield. In this study, we experimented to reproduce the pseudo shear force due to friction force on the butt end. We made clear the relationship between loads at cleavage failure and factors at splitting, to extract the factors that affect the expected cleavage fracture load. We also tried to formulate a general equation, and reported that the results were examined for their applicability.