Abstract

For the purpose of reducing dead load, an orthotropic steel deck is used in many long span bridges. The Honshu-Shikoku Bridges use orthotropic steel decks stiffened by closed section ribs (trough rib) as well. With the increase of the service years, fatigue cracks resulting from large vehicles have been observed. For the bead-penetrating cracks that initiate at weld root and grow toward bead surface in troughdeck weld, several repair methods have been studied. However, effective methods that are applicable from the underside of the deck are still under development. In this paper, development of plate-splicing methods that are applicable from the underside of the deck using Thread Rolling Screw and other fasteners and results of the fatigue tests to confirm their performances are described.