歴史的な街並を有する市街地における空地化とその環境影響の評価数値シミュレーションによる空地化が夏季熱環境と建物熱負荷量に及ぼす影響の解析

摘要

This study evaluates the impact of the vacant lots on the outdoor thermal environment and building heat load in the summer in an historical urban district using the 3D CAD-based thermal environment simulator. In this study, The spatial geometry and material data in 1979 and 2009 are collected and the 3D CAD model of the site scaled 1:500 is completed. As a result of numerical simulation, Heat Island Potential, which is the evaluation index of the sensible heat flux to the atmosphere, of the site where the adjacent site became vacant lots in 2009 is 20℃ at a maximum higher than that in 1979. Furthermore, the heat loads of the buildings adjacent to vacant lots is about 1.2~1.4 times as large as that of other buildings that have the equivalent total floor area and heat insulation capacity. Therefore, the increase of the vacant lots affects the changes of the outdoor thermal environment in the site and the heat load of the buildings adjacent to the vacant lots.%1．はじめに地方都市の中心市街地では，人口減少や商業施設の集客力低下，空地の増加といった衰退が問題となっている。中心市街地における空地の増加の中でも平面駐車場の増加は代表的な事例として取り上げられている。特に，かつて城下町や宿場町等であった地区は，それぞれの地域における重要な歴史的資産を含んでいるにもかかわらず，町家や蔵造りの建物が取り壊され，駐車場や戸建住宅への建替が進み，歴史的まちなみが消失する事例が報告されている。こ