Masonry Bearing Wall Supporting Steel Beam (Compromised fire rating?)

[drm4444]

I have an 8" cmu, 2-hr, masonry bearing, stair shaft wall. At each floor a steel beam bears on a bearing plate on the wall supporting hollow core precast plank. The beam stops 1" from the inside face of wall & the mason is planning to fill it in with mortar and/or maybe a soap block. Does this compromise the 2-hr rating?

 

[csd72]

Infill it with proper concrete or structural grout, not mortar.

I have read a few papers which have found that these things can be satisfactory.

http://www.seminarprojects.com/Thread-fire-behavior-of-steel-penetrating-concrete-wall

 

[GalileoG]

This is a grey area for me, but if the steel beam were to fail because of the fire, wouldn't this type of connection cause the steel beam to pull down the firewall with it?

Clansman

If a builder has built a house for a man and has not made his work sound, and the house which he has built has fallen down and so caused the death of the householder, that builder shall be put to death." Code of Hammurabi, c.2040 B.C.

 

[drm4444]

Thank you both for your responses. It does seem likely a beam connection failure would at least create a hole thru the stair wall. I would guess the answer to the proper way to detail the bearing plate connection would be similar to the how electrical boxes are installed on the outside of the wall. Maybe the beam needs to be spray-fireproofed.

 

[InDepth]

I believe the IBC requirement is that the if a beam is imcorporated into a fire wall it needs to have the same degree of fire resistance required for the fire wall itself....fireproof.

 

[BAretired]

I believe the steel beam does compromise the fire rating of the wall. It is best to avoid bearing the beam on the wall.

BA