Design guide for considering concrete breakout in shear using ACI 318 anchoring-to-concrete provisions October 2025 | Page 82

PROFIS ENGINEERING
Table 10. Design Strengths
Tension
Reference ESR-3814 Table 6A for ϕ steel values, Table 7 for ϕ concrete values and Table 11 for ϕ bond values. nominal strength design strength factored load % utilization comments
steel strength N sa( lb / anchor) 26,780
concrete breakout
N cbg( lb) 88,489 ϕ steel = 0.75 ϕN sa( lb / anchor) 20,085 ϕ seismic = N / A ϕ concrete = 0.65
ϕN cbg( lb) 57,518 ϕ seismic = N / A
N ua, i( lb / anchor) 625
N ua, g( lb) 10,000
( N ua, i / ϕN sa) 3.1 %
( N ua, g / ϕN cbg) 17.4 %
OK
OK CONTROLS
bond strength
N ag( lb)
128,489
ϕ bond = 0.65 ϕN ag( lb)
N ua, g( lb) 10,000
( N ua, g / ϕN ag) 12.0 %
OK
83,518
sustained tension
0.55 ϕ bond N ba, sustained( lb / anchor)
15,967
N ua, s( lb / anchor) 375
( N ua, s / 0.55ϕN ba, s) 2.4 %
OK
Shear
steel strength
V sa( lb / anchor)
16,070
ϕ steel = 0.65 ϕV sa( lb / anchor) 10,446
V ua, i( lb / anchor) 3125
( V ua, i / ϕV sa) 29.9 %
OK
concrete breakout( row 1)
V cbg, row 1( lb)
26,619
ϕ concrete = 0.75 ϕV cbg, row 1( lb) 19,964
V ua, row 1 = V ua, g / 3( lb) = 50,000 lb / 3 = 16,667 lb /
( V ua, row 1 / ϕV cbg, row 1) 83.5 %
OK
concrete breakout( row 2)
V cbg, row 2( lb)
52,551
ϕ concrete = 0.75 ϕV cbg, row 2( lb) 39,413
V ua, row 2 = 2V ua, g / 3( lb) =( 2)( 50,000 lb)/ 3 = 33,333 lb /
( V ua, row 2 / ϕV cbg, row 2) 84.6 %
OK
concrete breakout( row 3)
V cbg, row 3( lb)
70,866
ϕ concrete = 0.75 ϕV cbg, row 3( lb) 53,150
V ua, row 3 = V ua, g( lb) = 50,000 lb
( V ua, row 3 / ϕV cbg, row 3) 94.1 %
OK CONTROLS
concrete pryout
V cpg( lb)
176,978
ϕ concrete = 0.70 ϕV cpg( lb) 123,885
V ua, g( lb) 50,000
( V ua, g / ϕV cpg) 40.4 %
OK
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