Adhesive bonding – the future of shipbuilding in Europe
Considerable savings in weight can be achieved through the use of lightweight materials in ship construction. This reduces fuel consumption which generates both economic and environmental benefits. However, the reliability of lightweight models has been called into question, particularly the sections where different components are joined to one another. Looking to support the European shipbuilding industry, the GROWTH Programme funded an extensive investigation into the potential of adhesive bonding. Engineers with the University of Southampton in the United Kingdom participated in the research project, which was entitled BONDSHIP. Their focus was numerical modelling. Hot spots were identified with a superstructure model that calculated load levels based on the worst-case scenario. With respect to modelling the response of the adhesive itself, the multi-linear option of the ANSYS finite element modelling software package provided the best agreement between experimental and modelled results. The University of Southampton engineers also evaluated a number of different methods for predicting stress levels within the adhesive. They discovered that finite element techniques were more accurate, though more cumbersome, than their analytical counterparts. Finally, the behaviour of structures that had developed cracks was studied in detail. For instance, the relationship between load and crack size was examined both in the laboratory and via simulations. The preliminary results indicate that the actual energy required to induce a fracture was greater than that expected based on the modelling results, though further testing has been recommended.
