Sensitivity-based modal strain energy damage identification in an offshore catwalk to prevent environmental hazards

Catwalks are one of main components of each offshore complex. Their most important functionality is to provide connection between different parts such as the jackets and flare or between two neighboring jackets. Due to the catastrophic environmental and financial losses as well as the more importantly, loss of lives in case of the failure of an offshore platform and/or one of its elements, damage detection in this type of offshore structure is of a great importance. Such a concise damage identification can reduce the negative impacts of the failure of the structure on the marine habitat. Modal strain energy method is one of the most promising damage identifying methods which is based on variations in the dynamic characteristics of the structure. In this paper, a sensitivity-based modal strain energy damage identification technique is used to localize and quantify the assumed damages in an offshore catwalk structure. The finite element model of the structure is validated by comparing the outcomes of numerical and experimental modal analysis performed on the structure. This study shows that the implemented damage identification technique can be used to detect damages in real offshore truss structures with numerous members.