Abstract

Today’s merchant and passenger vessels are complex structures that operate in harsh environments with respect to static and cyclic loads and corrosion. Depleting funds for fleet renewal and increasing through-life cost of maintenance and repair are the principal factors that lead to the need to implement new solutions that are easy to apply and low cost. All this added to the growing need for lightening in the transport sector turn the FRP materials into the main candidates as drivers for this change. This present study within RAMSSES is focused on the compare a damage steel structures to repair composite patches. A representative structural detail of a cruise vessel was selected and designed as a demo case. The best patch solution was selected by FEM calculations, which have been fed from the mechanical test results of the composite material combinations, steel, surface treatments and adhesion joint of the one-shot dissimilar joints without adhesive. Fatigue tests have been carried out and monitoring by strain gauges and FBGs positioning and distribution in the high stress areas along the demonstrator. Fatigue tests have been carried out in the six demos to compare crack evolution in cracked Patched and Un-Patched demonstrators. As conclusion after the fatigue tests, composite patch works as crack arrested. Therefore, this behaviour represents an improvement of the 2.6 times of the fatigue life comparing UnPatched and Patched damaged steel.