| 摘要 |
PROBLEM TO BE SOLVED: To provide an H-steel beam of improved fire resistance achieved by reducing a deflection amount of the H-steel beam at a time of fire using a difference in thermal expansion, at the same time reducing material and construction costs involving fire-resisting coating.SOLUTION: An H-steel beam includes an upper flange, a lower flange and a web, and supports a concrete slab above. Only the lower flange, or the lower flange and a part or a whole of the web are covered by a fire-resisting material. The web is covered by the fire-resisting coating material to a height that conveys a design shear force for the web, from a bottom edge of the web, along with the lower flange. An open hole is pierced through a side surface of the web, and a part of the web from the lower edge to a location close to a lower edge of the open hole is covered by the fire-resisting coating material.SELECTED DRAWING: Figure 1 |
