延焼過程ネットワークのスケールフリー性に着目した木造密集地域における延焼危険建物の選択的除去効果の実証

抄録

 A scale-free power law distribution applies to fire-spreading networks in areas that are densely crowded with wooden-building, with each flammable wooden building as a node and its links to other buildings within fire-spreading distance of it. Based on the percolation theory of scale free networks, we have computed the percolation critical exponents and found that fire-spreading networks can be effectively disrupted by the targeted removal of each fire-spreading wooden building that links to six or more other such buildings. A targeted removal approach for the 84 highest-risk districts in Tokyo can prevent fire spread by removing 10-30% of flammable buildings, in contrast to random removal of 40-70% of flammable buildings. A detailed area survey and assortative coefficient indicate that cooperative rebuilding would be effective for a targeted removal approach.