FATIGUE COUNTERMEASURES FOR U-RIB TO DECK WELDED JOINTS FROM UNDERSIDE OF EXISTING ORTHOTROPIC STEEL DECKS

Abstract

 This paper proposes a countermeasure for fatigue cracks that propagate from the weld root of U-rib to deck welded joints to the deck plate or weld bead of orthotropic steel deck. Specifically, the lower flange of the U-rib is removed and the U-rib and deck plate welds are welded from the inside of the U-rib as a countermeasure method. First, to confirm the feasibility of this countermeasure with structural changes, the load-bearing capacity, workability of welding, and effects on asphalt pavement were verified. Next, changes in the local stress properties of the focused welds and other areas due to the countermeasures were confirmed by finite element analysis. Finally, the fatigue durability of the countermeasure was determined by fatigue tests.