Product Technical Guides : US-EN Anchor Fastening - August 2021 | Page 58

Table 32 — Load adjustment factors for # 8 rebar in uncracked concrete 1 , 2 , 3
# 8 Rebar uncracked concrete
Spacing factor in tension
ƒ AN
Edge distance factor in tension
ƒ RN
Spacing factor in shear 4
ƒ AV
┴ Toward edge
ƒ RV
Edge distance in shear
⃦ To and away from edge
ƒ RV
Concrete thickness factor in shear 5
Embedment h ef
in .
( mm )
9
( 229 )
12
( 305 )
20
( 508 )
9
( 229 )
12
( 305 )
20
( 508 )
9
( 229 )
12
( 305 )
20
( 508 )
9
( 229 )
12
( 305 )
20
( 508 )
9
( 229 )
12
( 305 )
20
( 508 )
9
( 229 )
12
( 305 )
20
( 508 )
1-3 / 4
( 44 )
n / a
n / a
n / a
0.23
0.17
0.10
n / a
n / a
n / a
0.02
0.01
0.01
0.05
0.03
0.01
n / a
n / a
n / a
5
( 127 )
0.59
0.57
0.54
0.31
0.23
0.13
0.54
0.53
0.52
0.11
0.07
0.04
0.22
0.14
0.07
n / a
n / a
n / a
6
( 152 )
0.61
0.58
0.55
0.33
0.25
0.14
0.55
0.53
0.52
0.14
0.09
0.05
0.29
0.19
0.09
n / a
n / a
n / a
7
( 178 )
0.63
0.60
0.56
0.36
0.27
0.16
0.55
0.54
0.53
0.18
0.12
0.06
0.36
0.23
0.12
n / a
n / a
n / a
8
( 203 )
0.65
0.61
0.57
0.39
0.29
0.17
0.56
0.55
0.53
0.22
0.14
0.07
0.40
0.29
0.15
n / a
n / a
n / a
9
( 229 )
0.67
0.63
0.58
0.42
0.31
0.18
0.57
0.55
0.53
0.26
0.17
0.09
0.43
0.34
0.17
n / a
n / a
n / a
10
( 254 )
0.69
0.64
0.58
0.45
0.33
0.20
0.58
0.56
0.54
0.31
0.20
0.10
0.46
0.38
0.20
n / a
n / a
n / a
11
( 279 )
0.70
0.65
0.59
0.48
0.36
0.21
0.58
0.56
0.54
0.35
0.23
0.12
0.50
0.40
0.23
n / a
n / a
n / a
11-1 / 4
( 286 )
0.71
0.66
0.59
0.49
0.36
0.21
0.59
0.56
0.54
0.37
0.24
0.12
0.50
0.41
0.24
0.58
n / a
n / a
12
( 305 )
0.72
0.67
0.60
0.52
0.38
0.22
0.59
0.57
0.54
0.40
0.26
0.13
0.53
0.43
0.27
0.60
n / a
n / a
13
( 330 )
0.74
0.68
0.61
0.56
0.41
0.24
0.60
0.57
0.55
0.46
0.30
0.15
0.56
0.45
0.30
0.63
n / a
n / a
14
( 356 )
0.76
0.69
0.62
0.60
0.44
0.26
0.61
0.58
0.55
0.51
0.33
0.17
0.60
0.47
0.34
0.65
n / a
n / a
14-1 / 4
( 362 )
0.76
0.70
0.62
0.61
0.45
0.26
0.61
0.58
0.55
0.52
0.34
0.17
0.61
0.48
0.34
0.66
0.57
n / a
16
( 406 )
0.80
0.72
0.63
0.69
0.50
0.30
0.62
0.59
0.56
0.62
0.40
0.21
0.69
0.52
0.37
0.70
0.60
n / a
18
( 457 )
0.83
0.75
0.65
0.77
0.57
0.33
0.64
0.60
0.57
0.74
0.48
0.25
0.77
0.57
0.39
0.74
0.64
n / a
20
( 508 )
0.87
0.78
0.67
0.86
0.63
0.37
0.65
0.61
0.57
0.87
0.56
0.29
0.86
0.63
0.42
0.78
0.67
n / a
22
( 559 )
0.91
0.81
0.68
0.94
0.69
0.41
0.67
0.63
0.58
1.00
0.65
0.33
0.94
0.69
0.44
0.82
0.71
n / a
22-1 / 4
( 565 )
0.91
0.81
0.69
0.95
0.70
0.41
0.67
0.63
0.58
0.66
0.34
0.95
0.70
0.45
0.82
0.71
0.57
24
( 610 )
0.94
0.83
0.70
1.00
0.76
0.44
0.68
0.64
0.59
0.74
0.38
1.00
0.76
0.47
0.85
0.74
0.59
26
( 660 )
0.98
0.86
0.72
0.82
0.48
0.70
0.65
0.59
0.84
0.43
0.82
0.50
0.89
0.77
0.61
28
( 711 )
1.00
0.89
0.73
0.88
0.52
0.71
0.66
0.60
0.94
0.48
0.88
0.53
0.92
0.80
0.64
30
( 762 )
0.92
0.75
0.95
0.55
0.73
0.67
0.61
1.00
0.53
0.95
0.55
0.95
0.83
0.66
36
( 914 )
1.00
0.80
1.00
0.67
0.77
0.70
0.63
0.69
1.00
0.67
1.00
0.91
0.72
> 48
( 1219 )
0.90
0.89
0.86
0.77
0.67
1.00
0.89
1.00
0.83
Spacing ( s ) / Edge distance ( c a ) / Concrete thickness ( h ), - in . ( mm ) ƒ HV
Table 33 — Load adjustment factors for # 8 rebar in cracked concrete 1 , 2 , 3
# 8 Rebar cracked concrete
Spacing factor in tension
ƒ AN
Edge distance factor in tension
ƒ RN
Spacing factor in shear 4
ƒ AV
┴ Toward edge
ƒ RV
Edge distance in shear
⃦ To and away from edge
ƒ RV
Concrete thickness factor in shear 5
Embedment h ef
in .
( mm )
9
( 229 )
12
( 305 )
20
( 508 )
9
( 229 )
12
( 305 )
20
( 508 )
9
( 229 )
12
( 305 )
20
( 508 )
9
( 229 )
12
( 305 )
20
( 508 )
9
( 229 )
12
( 305 )
20
( 508 )
9
( 229 )
12
( 305 )
20
( 508 )
1-3 / 4
( 44 )
n / a
n / a
n / a
0.42
0.40
0.38
n / a
n / a
n / a
0.02
0.02
0.01
0.05
0.03
0.02
n / a
n / a
n / a
5
( 127 )
0.59
0.57
0.54
0.56
0.50
0.44
0.54
0.53
0.52
0.11
0.08
0.05
0.22
0.16
0.10
n / a
n / a
n / a
6
( 152 )
0.61
0.58
0.55
0.60
0.53
0.46
0.55
0.54
0.53
0.14
0.10
0.06
0.29
0.21
0.13
n / a
n / a
n / a
7
( 178 )
0.63
0.60
0.56
0.65
0.57
0.47
0.55
0.54
0.53
0.18
0.13
0.08
0.36
0.26
0.16
n / a
n / a
n / a
8
( 203 )
0.65
0.61
0.57
0.70
0.60
0.49
0.56
0.55
0.54
0.22
0.16
0.10
0.44
0.32
0.19
n / a
n / a
n / a
9
( 229 )
0.67
0.63
0.58
0.75
0.64
0.51
0.57
0.56
0.54
0.26
0.19
0.12
0.53
0.38
0.23
n / a
n / a
n / a
10
( 254 )
0.69
0.64
0.58
0.80
0.67
0.53
0.58
0.56
0.54
0.31
0.22
0.13
0.62
0.45
0.27
n / a
n / a
n / a
11
( 279 )
0.70
0.65
0.59
0.86
0.71
0.55
0.58
0.57
0.55
0.36
0.26
0.16
0.72
0.52
0.31
n / a
n / a
n / a
11-1 / 4
( 286 )
0.71
0.66
0.59
0.87
0.72
0.56
0.59
0.57
0.55
0.37
0.27
0.16
0.74
0.54
0.32
0.59
n / a
n / a
12
( 305 )
0.72
0.67
0.60
0.91
0.75
0.57
0.59
0.57
0.55
0.41
0.30
0.18
0.82
0.59
0.35
0.61
n / a
n / a
13
( 330 )
0.74
0.68
0.61
0.97
0.79
0.59
0.60
0.58
0.56
0.46
0.33
0.20
0.92
0.67
0.40
0.63
n / a
n / a
14
( 356 )
0.76
0.69
0.62
1.00
0.83
0.62
0.61
0.59
0.56
0.51
0.37
0.22
1.00
0.74
0.45
0.65
n / a
n / a
14-1 / 4
( 362 )
0.76
0.70
0.62
0.84
0.62
0.61
0.59
0.56
0.53
0.38
0.23
0.76
0.46
0.66
0.59
n / a
16
( 406 )
0.80
0.72
0.63
0.91
0.66
0.62
0.60
0.57
0.63
0.45
0.27
0.91
0.55
0.70
0.63
n / a
18
( 457 )
0.83
0.75
0.65
1.00
0.70
0.64
0.61
0.58
0.75
0.54
0.33
1.00
0.65
0.74
0.67
n / a
20
( 508 )
0.87
0.78
0.67
0.75
0.65
0.62
0.59
0.88
0.64
0.38
0.75
0.78
0.70
n / a
22
( 559 )
0.91
0.81
0.68
0.80
0.67
0.64
0.60
1.00
0.73
0.44
0.80
0.82
0.74
n / a
22-1 / 4
( 565 )
0.91
0.81
0.69
0.80
0.67
0.64
0.60
0.75
0.45
0.80
0.82
0.74
0.62
24
( 610 )
0.94
0.83
0.70
0.85
0.68
0.65
0.61
0.84
0.50
0.85
0.86
0.77
0.65
26
( 660 )
0.98
0.86
0.72
0.90
0.70
0.66
0.61
0.94
0.57
0.90
0.89
0.80
0.68
28
( 711 )
1.00
0.89
0.73
0.95
0.71
0.67
0.62
1.00
0.63
0.95
0.92
0.83
0.70
30
( 762 )
0.92
0.75
1.00
0.73
0.68
0.63
0.70
1.00
0.96
0.86
0.73
36
( 914 )
1.00
0.80
0.77
0.72
0.66
0.92
1.00
0.94
0.79
> 48
( 1219 )
0.90
0.87
0.80
0.71
1.00
1.00
0.92
Spacing ( s ) / Edge distance ( c a
) / Concrete thickness ( h ), - in . ( mm )
1 Linear interpolation not permitted . 2 Shaded area with reduced edge distance is permitted provided rebar has no installation torque . 3 When combining multiple load adjustment factors ( e . g . for a four-anchor pattern in a corner with thin concrete member ) the design can become very conservative . To optimize the design , use
PROFIS Engineering or perform anchor calculation using design equations from ACI 318 Chapter 17 . 4 Spacing factor reduction in shear applicable when c < 3 * h ef
. ƒ AV , is applicable when edge distance , c < 3 * h ef
. If c ≥ 3 * h ef , then ƒ AV
= ƒ AN .
5 Concrete thickness reduction factor in shear , ƒ HV , is applicable when edge distance , c < 3 * h ef
. If c ≥ 3 * h ef , then ƒ HV
= 1.0 . ƒ HV
54 Anchor Fastening Technical Guide Edition 22 | 3.0 ANCHORING SYSTEMS | 3.2.2 HILTI HIT-HY 200 A / R V3 Hilti , Inc . 1-800-879-8000 | en español 1-800-879-5000 | www . hilti . com | Hilti ( Canada ) Corporation | www . hilti . ca | 1-800-363-4458