摘要 |
PROBLEM TO BE SOLVED: To provide a fire resistant structure of an exposed beam, capable of holding fire-resistant performance of 45 minutes semi-fireproof construction or more without depending on a burning allowance design, and being provided with the exposed beam in a state that a surface of wood is exposed with a considerable exposed area.SOLUTION: A fire resistant structure 10 of an exposed beam used in a wooden building having fire resistant performance of 45 minutes semi-fireproof construction or more is provided with: fire resistive covering materials 12 covering regions of 1/2 or more of beam depth of side face of both sides of the exposed beam 11, respectively, and having a function of preventing a covered and hidden part of the exposed beam 11 for 45 or more minutes from being burned and damaged in a case of fire; or fire resistive covering materials 12 having a function of preventing a covered and hidden part of the exposed beam 11 for 45 or more minutes from being burned and damaged in a case of fire and a function of preventing heat-deterioration, in a state that a region r of 30% or more, or preferably 36% or more of the beam depth in the lower part of the exposed beam 11 is exposed. |