All ACI-318-style failure modes for one cast-in headed bolt: steel, concrete breakout, pullout and pryout — with edge-distance and cracked-concrete effects, and the tension–shear interaction verdict.
All ACI-318-style failure modes for one cast-in headed bolt: steel, concrete breakout, pullout and pryout — with edge-distance and cracked-concrete effects, and the tension–shear interaction verdict.
Concrete breakout, not steel, governs most real anchors — embedment depth and edge distance are the design variables that matter. If you can, size the anchor so steel governs: that failure is ductile and visible. Everything here is a single anchor; groups interact through overlapping cones and need the full Chapter 17 treatment.
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With Eurocode selected the anchor is checked to EN 1992-4. The failure modes are the same family as in ACI 318 Chapter 17, but the numbers behind them differ: characteristic resistances are divided by partial factors instead of being multiplied by φ, the steel factor depends on the bolt’s fuk/fyk ratio, and cracked or uncracked concrete is handled by separate coefficients for the cone, pull-out and edge modes rather than by a ψc multiplier. The edge breakout expression also brings in the anchor diameter and its load-bearing length in a different way. The biggest practical difference is the interaction: Eurocode uses a circular rule for steel and a 1.5-power rule for the concrete modes, both limited to 1.0, instead of the ACI trilinear sum with its 1.2 limit. Pry-out uses k8 = 1 or 2, the usual values, although EN 1992-4 leaves k8 to the product’s European Technical Assessment.
With KDS selected the anchor follows KDS 14 20 54, the Korean anchor code. It is built on the same concrete capacity method as ACI 318 Chapter 17, with the same φ factors (0.75 and 0.65 for ductile steel, 0.70 for concrete without supplementary reinforcement) and the same trilinear interaction, so for most inputs the numbers match the AASHTO / ACI view. The differences you can see are the cap on futa (1.9fya and 860 MPa), the alternative 5/3-power breakout cap for deep headed bolts, and the reduced edge distance used for edge breakout in thin, narrow members, which the ACI view of this page does not apply.