We usually weld 3/4" dia. headed steel studs (6" long)to the top flange and grout solid the bottom 3 courses of cmu. In addition, you could also provide steel angles welded to the top flange to maintain alignment at the bottom of the wall. Good luck.
We have welded ASTM A706 reinforcing bars to the top flange of the beam, extending vertically the required development or splice distance. Then the CMU is placed over the bars and grouted.
You can also use deformed bar anchors as made by Nelson.
In the past, I have used weldable rebar in grouted cells at about 24" on center. The size and spacing of the rebar depend on the types of loads the wall will have to resist. A couple of other things to consider:
- Can the loads on the wall cause the beam to twist or bend in the out of plane direction?
- Is the wall cantilevered or is it braced at the top?
thanks for the help. this actually isnt a load bearing wall. it is to conceal a roof top airconditioning unit. so all it has to do is hold itself up and resist winds i suppose. also it is not braced on top.
Since it sounds like the CMU wall is cantilevered off the beam, wind load on this wall is going to want to twist the W14x48. Make sure this beam is sufficiently braced or is strong enough to resist the torsion that it may see.
the wall will only be about 3 rows of 8" cmu in height and about 16 feet in length (same length as the beam). the beam is bolted to the concrete roof deck and has a load bearing wall under the deck at each end. it has (2) C8x18.75 channels bolted perpendicular to the it. the channels are also bolted to the concrete roof deck and supported on the other end by a load bearing wall under the concrete deck. the unit is to rest on the two channels.
