斷面尺度因子對被覆Ｈ型鋼樑耐火性能之影響

黃育智

[中文摘要]

本研究主要在探討斷面尺度因子（W/D）對被覆鋼骨構件耐火性能之影響，試驗中以不同斷面尺度因子之H型鋼樑，四面噴附M1、M2兩種耐火被覆材料，待試體水份蒸發至衡重後，進行耐火試驗，以CNS 12514規定之建築物火災標準升溫曲線作為加熱條件，探討斷面尺度因子與被覆厚度及耐火時效之關係，並進行A、B尺度鋼樑耐火試驗結果比較。試驗結果顯示：
在A尺度耐火試驗方面，相同被覆材料及被覆厚度下，鋼樑之耐火時效會因斷面尺度因子的增加而延長；但是耐火時效和被覆厚度之比值（t/T）與斷面尺度因子（W/D）之關係，會因被覆厚度不同而迴歸成兩條直線；且斜率及截距，會因被覆材料不同而改變。在 B尺度耐火試驗方面，鋼樑若在無加載狀態下，因撓度而造成被覆材料龜裂或剝落的可能性極小，並不影響實際耐火試驗結果，故以B尺度代替A尺度鋼樑進行耐火試驗，應是可行。

[英文摘要]

The paper is study the effect of section scale factor for coating steel structure fireproof capacity. Using differ H style steel beam of section scale factor in test, and painted around M1、M2 two fireproof coating materials, after water evaporable of specimen to counterweight and proceed fire resisting test. Using the building fire standard rising temperature curve under CNS 12514 to be heated condition, and study the relationship of section scale factor, coating thickness and fireproof duration; then, proceed comparison with the result of A、B scale steel beam fire resisting test. According to ECCS fireproof design standard to make program simulative analysis and estimate painted differ section scale steel beam fireproof capacity of fire resisting covering material. The test result indicated: In the same covering material and thickness, the steel beam fireproof duration will lengthen caused by section scale factor under A scale fireproof test; the relationship between t/T of fireproof duration with covering thickness and section scale factor will regress change to two parallel by differ covering thickness. The slope of line and its intercept will changed by differ covering material. In B scale fireproof test, the possibility of coating material crack or flake is quite low cause by deformation when steel beam under non-repeating, and will not affect the result, so it is possible that B scale replaced A scale steel beam when proceeding fire resisting test.