Concrete Anchor Steel Strength (ACI 318-19 17.6.1 / 17.7.1)
The steel number every anchor tile's 'least of steel and concrete' note refers to, which nothing produced: Ase = (pi/4)(da - 0.9743/n)^2 from the thread callout, futa capped at min(1.9 fya, 125 ksi), Nsa = Ase futa (phi 0.75), Vsa = 0.6 Ase futa (phi 0.65, cast-in headed/hooked bolts). A 5/8-11 A307 checks 9.8 kip design tension and 5.1 kip design shear. ACI Chapter 17's own steel check - the AISC J3 bolt tiles are the structural-connection path with different numbers.
Formula and source
Ase = (pi/4)(da - 0.9743/n)^2; futa <= min(1.9 fya, 125,000 psi); Nsa = Ase futa, phiNsa = 0.75 Nsa (ductile, tension); Vsa = 0.6 Ase futa, phiVsa = 0.65 Vsa (ductile, shear, cast-in headed/hooked bolts).
The ACI 318-19 Sections 17.6.1 (steel strength in tension) and 17.7.1 (steel strength in shear, Eq. 17.7.1.2b) with Table 17.5.3 phi factors, by name; the Ase expression is the R17.6.1.2 commentary formula (also AISC Manual Table 7-18).
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