Influences of welding imperfections on buckling/ultimate strength of ship bottom plating subjected to combined Bi-axial thrust and lateral pressure

摘要

Characteristics of initial imperfections in panels and stiffeners due to welding are discussed based on the measured results. Then the buckling/ultimate strength of ship bottom plating as a stiffened plate subjected to combined hi-axial thrust and lateral pressure is investigated based on the results of new and recent analyses considering the influences of initial deflection and welding residual stresses. It has been concluded that: (1) buckling strength of a local panel between stiffeners is increased owing to the influences of lateral pressure and stiffeners; (2) welding residual stresses reduce both buckling strength and ultimate strength; (3) mode of initial deflection affects the ultimate strength a little, but the capacity in the post-ultimate strength range considerably under the longitudinal thrust.