Development of bottom structural protection to mitigate the consequences of ship grounding

Marine vessel operation is prone to various accidents, a significant proportion of which involve grounding. Such accidents often result not only in structural damage leading to their decommissioning, but also, in some cases, loss of life, total loss of vessels, and severe environmental damage. A number of researchers and research teams in various countries are working to develop ship bottom structures capable of mitigating grounding damage. The authors have proposed a number of design solutions for double bottom that can reduce damage from grounding. Most of the proposed design solutions involve the installation of sacrificial (or: deformable) structural protection elements within the bottom floor and girder webs, which collapse upon grounding. These deformable structural protection elements may include tubular sections (including those containing a working medium), corrugations, as well as shear-operated elements. A methodology for selecting the parameters of structural bottom protection components, based on plastic limit analysis methods, has also been developed. The effectiveness of the proposed design solutions was validated using the ANSYS LS-DYNA software package. It has been demonstrated that, compared to conventional bottom structures, the application of bottom structural protection incorporating tubular elements significantly reduces inner bottom plating deformations during vessel grounding. The proposed design solutions reduce the risk of damage to the double bottom plating, along with the machinery and equipment installed on it. This ensures that the vessel can continue to move under its own power after refloating.