I am working on a job with a shallow slab that uses an embed plate with weld studs. We specified a 5" embedment, but the contractor noted that because the plate is 1/2" thick, the weld studs would only be 4-1/2" long.
This made me wonder whether the effective embedment depth of the anchor is impacted by the thickness of the base plate, specifically, whether the tension breakout cone is affected, since the distance from the end of the weld stud to the underside of the embed plate would be shorter.
When I tested this in PROFIS by increasing the base plate thickness, the concrete breakout capacity did not change. Is this correct, or does plate thickness impact concrete breakout capacity?
Hi Micah,
Thank you for reaching out. The effective embedment is always measured downwards starting from the surface of the substrate/base material. ACI 318 Chapter 17 Anchoring to Concrete assumes a rigid baseplate. Therefore, the thickness of the baseplate/fixture does not affect the anchor calculations. For reference, please see page 56 of the PROFIS Engineering Anchoring to Concrete Design Guide.
If you have any further questions, feel free to reach out to us at hnatechnicalservices@hilti.com or give us a call at 877-749-6337.
Regards,
Kevin