Strain Analysis of Traditional Japanese Timber Joints under Tensile Loading
The strain distribution of traditional joints under tensile loading was analyzed using the digital image correlation technique (DIC) and the finite element method (FEM) Two types of splice joints; Kama Tsugi (a half lapped "gooseneck" splice joint) and Okkake Daisen Tsugi (a wedged tabled joint with dowels) were studied. The proportions of the joints were altered in order to investigate the effect of shear plane (a plane parallel to the grain) length on tensile strength. In both types of joints, shear strain was concentrated near the re entrant corner of the joints. The degree of shear strain concentration tended to increase as the shear plane length increased. It was found that the tensile strength could be estimated by considering the degree of shear strain (stress) concentration.