Wind-induced fragility of a group of three gable-roof buildings with different roof slope and building spacing

•Interference effects remarkablely affect the wind fragility of a group of buildings.•Dependency of building fragility with small and large roof slope are opposite.•Determine the most favorable and unfavorable building layout of a group of buildings. The influence of the roof slope, building spacing, building orientation and joint probability of wind speed and direction on the wind-induced fragility (WIF) of a group of three gable-roof buildings was investigated. The results show that wind interference effects on the WIF of buildings are significant. The dependency of the WIF of buildings with a small roof slope of 10° is nearly opposite from that with a large roof slope of 35°. When the roof slope is 10°, wind shielding effects make the WIF of the center and downstream buildings less than that of the isolated building, the WIF decreases with the decrease of building spacing, and the maximum increase of the minimum critical wind speed among all wind directions reaches 14.1%. When the roof slope is 35°, wind amplification effects make the WIF of the upstream and center buildings greater than that of the isolated building, the WIF increases with the decrease of building spacing, and the maximum decrease of the minimum critical wind speed is 7.2%. When the buildings are located in Fuzhou, the WIF reaches the minimum (it means the most favorable building arrangement) for buildings with a roof slope of 10°, and it reaches the maximum (it means the most unfavorable building arrangement) for buildings with a roof slope of 35° at the building orientation of about 30° with a small building spacing.