CMU Shear/Bearing Wall with C joists
CMU Shear/Bearing Wall with C joists
(OP)
In a 2 story building - say 40' L x 20' W with the longer walls being reinforced CMU and the 20' side being spanned by cold formed steel C joists, could the C joists into the CMU wall be counted on at all for lateral force resistance - like a moment frame?
The intent is to have an open floor space, so that rules out any shear walls running perpendicular to the reinforced CMUs. Only one end of the building is going to have a rear wall (would look U shaped in plan view). I don't think that single perpendicular wall in the rear could count as a shear wall for the entire 40' length of the building.
Any ideas on how to take care of the lateral forces in the 20' direction?
The intent is to have an open floor space, so that rules out any shear walls running perpendicular to the reinforced CMUs. Only one end of the building is going to have a rear wall (would look U shaped in plan view). I don't think that single perpendicular wall in the rear could count as a shear wall for the entire 40' length of the building.
Any ideas on how to take care of the lateral forces in the 20' direction?






RE: CMU Shear/Bearing Wall with C joists
RE: CMU Shear/Bearing Wall with C joists
The job has become a build first, engineer later type of mess, and I have to work within the abilities/limitations of the current contractor and budget. This was not my job from the start.
I was considering using a reinforced concrete frame, rather than steel, to easily bond into the long CMU walls. The problem is this method (whether RC or steel) is that it won't be tied into the floor system that was scheduled to be used. I can't see how I could still use the C-joist floor system. If I went with steel id have to worry about tying or isolating the steel from the CMU wall.
I'm not following you exactly with the horizontal truss at the roof level. I was planning on counting on the diaphragm action of the C joists / decking to distribute load between the CMU shear wall and whatever I use on the other end.
Any suggestions on the best way to proceed? Cost is becoming a major issue at this point.
RE: CMU Shear/Bearing Wall with C joists
Do the C joists occur at the floor as well as at the roof? Maybe a few details on how it is intended to be built would help. I agree that building first and designing later is doomed to be a 'mess'.
I don't like the idea of a concrete rigid frame. Detailing the reinforcement to make the joints efficient is very difficult, and is difficult to build.
RE: CMU Shear/Bearing Wall with C joists
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RE: CMU Shear/Bearing Wall with C joists