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Through bolt connection

Michael Val

Civil/Environmental
Joined
May 6, 2025
Messages
2
Hello everyone, I could use your expertise. I'm working with through bolts anchored in a concrete slab, and I'm referencing Eurocode for design. Unfortunately, there’s limited guidance available for this specific case.
Here’s the situation (please refer to the image below):
1752412787469.png1752413144740.png
green - beams
yellow - slab
I'm only concerned with the concrete slab—not the bolt or base plate. Based on my understanding, I need to check for the following failure modes:

Concrete cone failure due to tension from moment
Concrete pry-out failure
Concrete bearing compression

Am I on the right track?

I also have additional questions:
  1. Edge Distance 1752413986311.png: If the anchor is placed in the middle of a slab bounded by beams, how should I treat edge distance? Can I assume the edge effects (like blow-out failure) are negligible, or do I need to account for them?
  2. Eccentricity 1752413992380.png: Since the tension arises from moment, should I be concerned about eccentric loading effects on the anchor?
Thank you everyone.
 
are you really anchoring to the slab in the traditional sense? It doesn’t seem like anchorage design really applies at all. The bolts aren’t pulling out of the concrete by some form of bond but through a backer plate to make a bolted clamp like connection. The bolts would be in tension as a result to create a friction force to prevent movement, like a slip critical connection. From there the forces are distributed through a thick plate across the slab. The slab needs to be checked for shear and bending as a result. Likely bi axial loading.
 

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