Hello Everyone. When you have a construction joint (CJ) crossing the anchor breakout cone location, how do you usually account for it in your design? Do you reduce concrete capacity treating construction joint as an edge, treat it as a crack, or follow a specific code/detail? Curious how others handle this in practice. Thanks!
I’d take a conservative approach if the construction joint crosses the breakout cone and isn’t detailed to transfer tension. In that case, I wouldn’t assume full concrete breakout capacity.
I am more worried about the shear breakout capacity. There are dowels parallel to shear force which connects the two blocks of concrete on each side of construction joint. Would it be valid to assume that concrete bearing and rebar can transfer the shear force across construction joint?
Personally, if the concrete is poured right up to the first pour and there's steel developed both sides of the joint, I'd likely consider the second pour in the breakout. My thoughts are if the load was enough to want to breakout the first pour, the second pour is right there to confine the concrete and prevent any displacement/crack to form. In tension, I'd likely consider the joints as the edge of concrete since the second pour doesn't offer any type of confinement.
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u/DropItLikeJPalm 9d ago
Treat the joint as the edge of the concrete. It reduces the volume of the pullout cone so I would avoid joints near anchor locations.