Cyclone vulnerability of traditional timber housing in coastal regions of Madagascar

Madagascar is amongst the most vulnerable countries in the world to natural disasters. It is exposed to frequent cyclones and large proportions of its building stock collapse under the associated high wind loads and flood events. In the coastal regions of the country, domestic construction is based on timber, with infill walls and roofing made of eucalyptus, bamboo and traveller's palm. Carpentry connections such as pegged mortise and tenon joints are formed between timber members and are a key part of the load paths through the structure. This study takes a structural analysis of the timber structure and experimental testing of materials and components, and pairs it with analysis of the wind loads. In the framework we propose, the statistical variation of various parameters is included, allowing an estimate of the risk to a population of buildings in a given year: information which can be used to justify and target investments to improve resilience.