Headed stud anchors in CMU
Headed stud anchors in CMU
(OP)
This maybe a simple question, but want to make sure I set this up correctly. In the ACI 530-11 code section 2.1.4.3.1.1 and 2.1.4.3.2 for the allowable tension and shear loads for anchors in CMU. For the steel portion of the checks, there is the specified yield strength of steel for reinforcement and anchors (fy) as part of the equation. My case is where I have a steel bar joist bearing on top of a CMU wall. Embed plate as a bearing plate with headed stud anchors to resist shear and tension. For tension the equation is Bas = 0.6Abfy and for shear Bvs = 0.36Abfy. For the A307 steel (headed studs) do I use 36 ksi for the fy or something else.
Side question: the ACI 530-11 provides a nice equation for the Apt for multiple anchors. Anyone have an equation for multiple anchors in shear to calculate Apv?
Thanks and have a great day.
Side question: the ACI 530-11 provides a nice equation for the Apt for multiple anchors. Anyone have an equation for multiple anchors in shear to calculate Apv?
Thanks and have a great day.






RE: Headed stud anchors in CMU
Why the large increase? FYI, I'm looking at allowable stress.
Thanks.
RE: Headed stud anchors in CMU
RE: Headed stud anchors in CMU
I have not looked in a while. But CMACN may have some equations for Apv in a past Masonry Chronicle. See http://cmacn.org/masonry-chronicles.htm#past
In 08 or 11, ACI 530 changed anchor bolt equations so there was better agreement between ASD and Strength design. In 05, there were significant differences in the ASD and strength capacity.
RE: Headed stud anchors in CMU
RE: Headed stud anchors in CMU
Typically it will not govern but it can.
consider 1/2" headed stud in tension w/ 8" embed in 12"CMU
Apt = π82 = 201 in2
Bab = 1.25Apt sqrt(f'm) = 1.25(201)sqrt(1500) = 9730 lbs
Bas = 0.6Abfy = 0.6(0.20)(51000) = 6120 lbs