木質小片断熱材を充填した木造外壁の耐火性能 : 遮熱性および構造安全性 : グラスウール充填壁との比較 Fire safety of wooden walls filled with wood shaving insulation panels : Its heat shielding effect and structural safety compared to fiberglass-filled walls
プレーナー屑を型枠中で密度110kg/m<Sup>3</Sup>に圧縮し, これを防湿フィルムで被覆した断熱材(木質小片断熱材)を製造した。この断熱材を木造軸組のモデル壁体に充填し, 耐火試験を行って, 遮熱性と柱の断面欠損を調べた。比較対照は中空壁およびグラスウール充填壁とした。その結果, 木質小片断熱材を充填した壁体では, 遮熱性が中空壁やグラスウール充填壁よりも優れ, 準耐火構造相当の遮熱性が認められた。また, 加熱60分後の柱の断面欠損率は, 木質小片断熱材を充填した場合, グラスウール充填壁の約60%に抑制され, 構造安全性の面でも木質小片断熱材の優位性が示唆された。
The insulation panels developed in this study are composed of wood shavings compressed into a mat with a density of 110 kg/m<Sup>3</Sup> without any binder. This mat is lapped with plastic film that works as a damp proof course. This paper describes fire tests conducted with a full-scale-thick wooden frame wall that was sandwiched with wood-fiber cement board and plasterboard. The test wall was filled with 100-mm-thick wood shaving insulation panels or fiberglass insulators, or a hollow. These three types of wall were examined for heat shielding effect and cross section loss of wood column (105mm by105mm). The results revealed that the test wall filled with our insulation panels had a higher heat shielding performance than other walls. This is because charring of wood shavings generates water and some of it remains near the rear surface of the panels due to an existence of plastic film, and consequently, the water consumes vaporization energy and resulted in keeping a temperature lower than of around 100°C. The heat shielding performance was found to have a quality equivalent to the 60-minute quasi-fireproof performance stipulated in the Building Standard Law of Japan. Furthermore, our insulation panel was found to provide a wall less cross section loss of wood column than a wall filling with fiberglass. This suggests that wood shaving insulation panels are superior to fiberglass in terms of structural safety by fire as well as heat shielding performance.
- 木材保存 = Wood preservation
木材保存 = Wood preservation 34(2), 60-68, 2008-03-25