Durability of an adhesively bonded joint between steel ship hull and
composite superstructure pre-exposed to marine environment.
Abstract
This paper outlines an experimental investigation into the durability of
large-scale adhesively bonded joints immersed in a 3.5 wt% NaCl
solution for 10 weeks at 50°C. Two aged and one unaged specimen were
subjected to tensile testing up to failure, and three aged and one
unaged specimen were loaded up to ~3.5 million fatigue
cycles followed by a residual tensile test. The shear, longitudinal, and
peel strain values in adhesive bulk (evaluated by the digital image
correlation (DIC) technique) are significantly higher at the gripped
sides due to the asymmetrical design of the steel brackets. The shear
strength and stiffness of statically and fatigue tested specimens are
found to be identical. The shear strength values are significantly
higher than the requirements following from the design. All specimens
failed by sudden delamination of the composite plate. Post-mortem
analysis showed no corrosion travel at the interface of steel and
adhesive.