Stress Concentration Factor and Tensile Strength of Gooseneck Joint under Uniaxial Tensile Load

Abstract

Japanese forest is expected as source of structure material, because trees planted in post war era have been grown up．In Japan, houses have been made by wood traditionally and wood is used as structural material such as pillar and beam. In order to use wood as a structural material, a joint is necessary. The shapes of these traditional joints are determined empirically and used without any analytical evaluation such as stress analysis. Therefore, stress analysis is necessary in order to use such joints efficiently. In our study, we estimate joint stress concentration factor of gooseneck joint under uniaxial tensile load analytically. Gooseneck joint is one of typical joint in japan and consist of male part and female part. In our previous study, we conducted a tensile test and measure the strain distribution of the joint by digital image correlation method (DIC) and FEM analysis. From these results, we proposed the formulae which give the stress concentration factors for male and female parts. In this study, we conducted tensile strength tests of goose-neck joint with varying the dimension parameter and estimating and tensile strength of the various shapes of the joint under uniaxial load. From the result, we examine the relation between the joint stress concentration factor and tensile strength of the joint for confirming the validity of using the joint concentration factor to evaluate the tensile stress of the joint.