Effect of Corrosion and Inclined Angle on Static Strength of Fillet-Welded Joint of 500 MPa-Class Steel

There are reported cases of serious accidents in ship hull structures of aged ships due to corrosion of steel after long period of use. This paper presents basic information on the effect of corrosion on static strength, that is, tensile strength, bending strength and shear strength, of fillet-welded joints of 500MPa-class steel used for ship hull construction. It is based on experimental results using specimens made of material of corroded fillet-welded joints of actual old ships and as-fabricated fillet-welded joint and simulated corroded fillet-welded joint. And also the effect of inclined angles on perpendicular direction shear strength of fillet-welded joint is investigated. Basically, static strength of the fillet-welded joint is affected by the (R) ratio of thickness of steel plates to total thickness of throat of the weld metal. When R was greater than 1.0, fracture occurred at weld metal under tensile stress condition or shear stress condition. However, under bending stress condition fracture at weld metal occurred when R was greater than 1.4. The effect of inclined angles on shear strength of fillet-welded joints is also presented.