Product Overview
TECHNICAL GUIDE – MECHANICAL ANCHORS ©2021 DEWALT – REV. E
A
NCHORS & FASTENERS
INSTALLATION SPECIFICATIONS (SD)
Mechanical anchors
12
INSTALLATION SPECIFICATIONS (SD)
Screw-Bolt+ Installation Specifications in Concrete and Supplemental Information
1,2,3,4
CODE LISTED
ICC-ES ESR-3889
Anchor Property/
Setting Information
Notation Units
Nominal Anchor Diameter (inch)
1/4 3/8 1/2 5/8 3/4
Head Style
-
- Hex or Flat Head Hex or Flat Head Hex or Flat Head Hex Head Hex Head
Nominal anchor diameter d
a
in.
(mm)
0.250
(6.35)
0.375
(9.525)
0.500
(12.7)
0.625
(15.9)
0.750
(19.05)
Minimum diameter of hole
clearance in fixture
8
d
h
in.
(mm)
3/8
(9.5)
1/2
(12.7)
5/8
(15.9)
3/4
(19.1)
7/8
(22.2)
Drill bit diameter (ANSI) d
bit
in. 1/4 3/8 1/2 5/8 7/8
Minimum nominal
embedment depth
5
h
nom
in.
(mm)
1-5/8
(41)
2-1/2
(64)
2
(51)
2-1/2
(64)
3-1/4
(83)
2-1/2
(64)
3
(76)
4-1/4
(108)
3-1/4
(64)
4
(64)
5
(127)
4-1/4
(108)
Effective Embedment h
ef
in.
(mm)
1.20
(30)
1.94
(49)
1.33
(34)
1.75
(44)
2.39
(61)
1.75
(44)
2.17
(55)
3.23
(82)
2.24
(57)
2.88
(73)
3.73
(95)
3.08
(78)
Minimum hole depth h
hole
in.
(mm)
2
(51)
2-7/8
(73)
2-3/8
(60)
2-7/8
(73)
3-5/8
(92)
2-7/8
(73)
3-3/8
(86)
4-5/8
(117)
3-5/8
(92)
4-3/8
(111)
5-3/8
(137)
4-5/8
(117)
Minimum concrete member
thickness
h
min
in.
(mm)
3-1/4
(83)
4
(102)
3-1/2
(89)
4
(102)
5
(127)
4-1/2
(114)
5-1/4
(133)
6-3/4
(171)
5
(127)
6
(152)
7
(178)
6
(152)
Minimum edge distance
6
c
min
in.
(mm)
1-1/2
(38)
c
min
= 1-1/2 (38)
for s
min
≥ 3 (76)
s
min
= 2 (51)
for c
min
≥ 2 (51)
1-3/4
(44)
1-3/4
(44)
1-3/4
(44)
Minimum spacing distance
6
s
min
in.
(mm)
1-1/2
(38)
2-3/4
(70)
2-3/4
(70)
3
(76)
Minimum overall
anchor length
7
ℓ
anch
in. 1-3/4 2-5/8 2-1/2 3 4 3 4 5 4 5 6 5
Maximum manual
installation torque
T
inst,max
ft.-lbf.
(N-m)
19
(26)
25
(34)
25
(34)
25
(34)
40
(54)
45
(61)
45
(61)
60
(81)
60
(81)
70
(95)
Maximum impact
wrench power (torque)
T
impact,max
ft.-lbf
(N-m).
150
(203)
300
(407)
300
(407)
700
(950)
700
(950)
Hex Head
Wrench socket size - in. 7/16 9/16 3/4 15/16 1-1/8
Maximum head height - in. 21/64 3/8 31/64 37/64 43/64
Max washer diameter - in. 37/64 3/4 1-1/16 1-1/8 1-13/32
Flat Head
Driver size - in. T-30 T-50 T-55 - -
Max head diameter - in. 17/32 57/64 1 - -
Countersunk angle - in. 82 82 82 - -
Effective tensile stress area
(screw anchor body)
A
se
in
2
(mm
2
)
0.045
(29.0)
0.094
(60.6)
0.176
(113.5)
0.274
(176.8)
0.399
(257.4)
Minimum specified ultimate
strength
f
uta
ksi
(N/mm
2
)
100
(690)
105
(724)
115
(794)
95
(656)
95
(656)
Minimum specified yield strength f
y
ksi
(N/mm
2
)
80
(552)
84
(579)
92
(635)
76
(524)
76
(524)
Mean
axial
stiffness
9
Uncracked concrete
b
uncr
lbf/in 1,252,000 1,157,000 1,014,000 919,000 1,028,000
Cracked concrete
b
cr
lbf/in 355,000 330,000 349,000 378,000 419,000
For SI: 1 inch = 25.4 mm; 1 ksi = 6.894 N/mm
2
; 1 ft-lb = 1.356 N-m; 1 lb = 0.0044 kN.
1. The information presented in this table is to be used in conjunction with the design criteria of ACI 318-14 Chapter 17 or ACI 318-11 Appendix D, as applicable.
2. For installations in the topside of concrete-filled steel deck assemblies with minimum concrete member thickness, h
min,deck
, of 2.5 inches above the upper flute (topping thickness). See the table
for anchor setting information for installation on the top of concrete-filled steel deck assemblies and the top of concrete over steel deck installation detail.
3. For installations in the topside of concrete-filled steel deck assemblies with sand-lightweight concrete fill, the maximum installation torque, T
inst,max
, is 18 ft.-lb.
4. For installations through the soffit of steel deck assemblies into concrete, see the design information table for installation in the soffit of concrete-filled steel deck assemblies and the installation
details in the soffit of concrete over steel deck for the applicable steel deck profile. Tabulated minimum spacing values are based on anchors installed along the flute with axial spacing equal to
the greater of 3h
ef
or 1.5 times the flute width.
5. The embedment depth, h
nom
, is measured from the outside surface of the concrete member to the embedded end of the anchor.
6. Additional combinations for minimum edge distance, c
min
, and minimum spacing distance, s
min
, may be derived by linear interpolation between the given boundary values for the 3/8-inch
diameter anchors.
7. The listed minimum overall anchor length is based on the anchor sizes commercially available at the time of publication compared with the requirements to achieve the minimum nominal
embedment depth. The minimum nominal length for hex head anchors is measured from under the head to the tip of the anchor, the minimum nominal length for flat head anchors is measured
from the top of the head to the tip of the anchor.
8. The minimum diameter of fixture hole clearance is for the body of the anchor to pass through structural steel members; clearance holes may be 1/8-inch less than tabulated values (same as
nominal drill bit diameter) provided the screw anchors are installed through light gauge cold-formed steel members or wood members.
9. Mean values shown, actual stiffness varies considerably depending on concrete strength, loading and geometry of application.