cmu bond beams
cmu bond beams
(OP)
should horizontal rebar run continuous through control joints in cmu walls? I think it should because it can be used as diaphragm chord reinforcement (unless other measures are taken). I think the percentage of horizontal steel in the wall is typically low enough so that the continuous rebar doesn't lock the joint.
I ask the question because I recently saw this detail on another structural engineers set of plans.
I ask the question because I recently saw this detail on another structural engineers set of plans.






RE: cmu bond beams
Another option is to analyze your building as a "C" shape at the joint. You have to analyze your building for torsion. Also, lateral deflection must be checked.
RE: cmu bond beams
RE: cmu bond beams
RE: cmu bond beams
Since I live in Florida and I design most of CMU walls as shear walls, bond and tie beams become diaphragm chords.
Good luck
RE: cmu bond beams
Lufti, thanks much for the offer. My email is b.bidonde@ctmale.com. We run AutoCAD 2002 here, or you can also send it as a tiff or adobe image, whatever works best for you.
RE: cmu bond beams
I think you have control joints confused with expansion joints. You mentioned greased bars - these are only used at expansion joints to allow the expanding members to move without restraint. Reinforcing should be continuous across control joints. These joints are for aesthetic purposes as they help control the cracking pattern in the finished surface. Good luck.
RE: cmu bond beams
I don't have the two confused. The drawings that I saw by another structural engineer had the greased bars in the control joints in a CMU wall - it's not my design. You typically wouldn't have expansion joints in a CMU wall because it shrinks. Nonstructural reinforcement should not run continuous through a control joint according to NCMA TEK NOTE 10-2B, but structural reinforcement such as rebar for diaphragm chords should. The drawings in question by the other engineer appeared to have ALL horizontal reinforcing bars stopping at the control joints.