Abstract
The stress distribution in a bolted joint and the pressure distribution on the bearing surface of a hexagon nuts with flange have been examined by the three-dimensional photoelastic experiment. The experiment shows that the stress distribution in a bolted joint is axially asymmetrical, because the screw part has an axi-asymmetrical shape. The pressure distribution on the bearing surface of hexagon nuts with flange has the asymmetry corresponding to that stated above. The radial distribution of the bearing surface pressure concentrates at the inner part of the flange, while the pressure on the bearing surface at the outer part of the flange is reduced to almost zero. Namely, the pressure on the bearing surface of the hexagon nuts with flange is not uniformly distributed. Accordingly, the improvement of the fastening function of a hexagon nuts with flange is necessary.
