Historic masonry lighthouses are important navigational aids but also historical and cultural landmarks, that face increasing threats from environmental factors like severe weather and rising sea levels. Situated in the North Sea, the Bell Rock, the world’s oldest surviving sea-washed lighthouse has guided mariners for over 200 years whilst being exposed to the climatic elements. With support from its current managing authority in Scotland, the Northern Lighthouse Board (NLB), this research study aims at investigating the structural reliability of this 35m tapered cylindrical tower, which largely relies to its self-weight and dovetail joints to withstand the force of the North Sea. Structural analysis is undertaken by Finite Element Modelling with the software ABAQUS, where a variety of load scenarios have been considered. With the focus being on wind and wave loading, extensive research and analytical work provided realistic load cases and determined critical combinations. Assessment of results takes place in the form of stress and displacement criteria, as well as the failure mechanisms of overturning and sliding. Based on this numerical output and comparison with data from case studies and site observations, areas of further research are identified.
Marinelli et al. (2026) studied this question.