Fire resistance of bracing members

[bakhtiyari]

The bracing members are somehow considered as primary structural frame according to IBC commentary. In the other side, a reduction in fire resistance rating of the structural members is allowed in section 403.2 for high-rise buildings with an exception for columns. My question is that if this reduction is also allowed for bracing members or they need to be considered like columns without a reduction in fire resistance rating. Any comment is highly appreciated.

 

[ADAguy]

Loss of unprotected braces can lead to progressive failures of main supports.

 

[bakhtiyari]

Thank you for your comment. Yes you are right, but my question is if the reduction of fire resistance rating due to sprinkler installation is allowed (like beams) or not (like columns)?

 

[Jay Smith]

Is there some indication elsewhere in the code that other members could be assumed to be part of the intended requirement along with columns supporting floors?

 

[bakhtiyari]

Actually I coudn't find such an indication.

 

[bakhtiyari]

* couldn't

 

[steveray]

The way it is written, technically the bracing would not be included.....But that would be good design.....