AbstractThe breakwater at Tristan da Cunha suffered structural damage during heavy seas that battered the island during winter 2010 (June and August). The damage was of such a nature that emergency repairs had to be designed and constructed before the onset of the next winter season. The damage entailed the loss of primary armour units (3.5t dolosse) at the head of the western breakwater exposing the under-layer rock as well as some slight movement of the end section of the crest slab (cap). Further damage to the breakwater head (130m offshore in 6m water depth) was reported one month later; with the crest slab being lifted further by approximately 500mm. The construction methodology during the emergency repair design process, laboratory validation and onsite construction is covered in this manuscript.
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