On July 4, Nagoya City released details on 50 city-owned buildings across the city that face a high risk of collapse in an earthquake producing a seismic intensity (shindo) level of 6+ or above. All 50 buildings were built before the 1981 change in earthquake-resistant construction methods. 45 of those buildings are public housing complexes which are home to as many as 2,500 households.
The building with the lowest earthquake resistance was the Kobayashi-so Public Housing complex in Osu, Naka Ward. Built in 1958, the 4-storey concrete apartment block was found to have a seismic index of just 0.1. A seismic index below 0.3 poses a high risk of collapse in an earthquake producing a shindo level of 6 ~ 7. Current earthquake-resistant standards require a seismic index of 0.6 and above. The city plans to vacate the building early next year and provide financial assistance to help residents move to new accommodation.
44 of the 45 housing complexes will be rebuilt, while one of the buildings will be retrofitted. Rebuilding is expected to take around three years, but resistance from long-term residents could slow down the process. Rent in newer, earthquake-resistant buildings, however, is expected to be two to three times the rent of non-earthquake resistant buildings.
Nagoya’s castle tower was found to have a seismic index of 0.14 and the city is considering limiting access to the public. The reinforced-concrete tower was built in 1959.
NHK, July 4, 2016.
The Chunichi Shimbun, July 5, 2016.