テレビ塔の防火対策

DOI Web Site

書誌事項

タイトル別名
  • Protection of Television Tower against Fire Damage.
  • テレビトウ ノ ボウカ タイサク

この論文をさがす

抄録

On the construction of television towers which have recently increased rapidly in numbers all over Japan, great emphasis is laid on the bearing power against wind or earthquake, but little consideration is paid to fire protection.<br>If fire breaks out in a big wooden house just under the tower, strength of angles of the tower heated by rising hot current from the burning house may be weaken, which may results in the fall of the tower.<br>In this report it is assumed that the strength of undamaged angles is twice as strong as that of the damaged ones in case of strongest wind and they are heated up to 550°C in case of calm ; the temperature at which strength of steel drops to 1/2 of the initial one.<br>The writer has been studying the temperature distribution of rising stream from a rectangular heat source. The height of rising current at which temperature of stream drops to 550°C can be calculated based upon the study if the floor area of the burning house is given.<br>According to his study, cylinder-shaped concrete covering may be recommended as fire protection of the tower against heat damage. The covering must be thick enough so as to keep angles below 550°C during fire. Thickness of the covering can be calculated from thermal conductivity and heat transfer coefficient of concrete at high temperature.<br>If a wooden house with floor area 5m × 5m is at the foot of a tower, the tower is required to be covered with concrete covering of not less than 5cm thickness and up to 15m high from the ground.

収録刊行物

詳細情報 詳細情報について

問題の指摘

ページトップへ