Product Overview
TECHNICAL GUIDE – MECHANICAL ANCHORS ©2021 DEWALT – REV. E
A
NCHORS & FASTENERS
STRENGTH DESIGN (SD)
19
Mechanical anchors
FACTORED RESISTANCE STRENGTH (ØN
n
AND ØV
n
) CALCULATED IN ACCORDANCE WITH ACI 318-14, CHAPTER 17:
1- Tabular values are provided for illustration and are applicable for single anchors installed in normal-weight
concrete with minimum slab thickness, h
a
= h
min
, and with the following conditions:
- c
a1
is greater than or equal to the minimum edge distance, c
min
(table values based on c
a1
= c
min
).
- c
a2
is greater than or equal to 1.5 times c
a1
.
2- Calculations were performed according to ACI 318-14, Chapter 17. The load level corresponding to the
controlling failure mode is listed. (e.g. For tension: steel, concrete breakout and pullout; For shear: steel, concrete
breakout and pryout). Furthermore, the capacities for concrete breakout strength in tension and pryout strength in
shear are calculated using the effective embedment values, h
ef
, for the selected anchors as noted in the design
information tables. Please also reference the installation specifications for more information.
3- Strength reduction factors (ø) were based on ACI 318-14 Section 5.3 for load combinations.
Condition B is assumed.
4- Tabular values are permitted for static loads only, seismic loading is not considered with these tables.
5- For designs that include combined tension and shear, the interaction of tension and shear loads must be
calculated in accordance with ACI 318-14, Chapter 17.
6- Interpolation is not permitted to be used with the tabular values. For intermediate base material compressive
strengths please see ACI 318-14, Chapter 17. For other design conditions including seismic considerations
please see ACI 318-14, Chapter 17.
Ca1
Ca2
ha
Tension and Shear Design Strength at Minimum Edge Distance, c
min
for Screw-Bolt+ in Cracked Concrete
Nominal
Anchor
Diameter
(in.)
Nominal
Embed.
h
nom
(in.)
Minimum Concrete Compressive Strength
f’c = 2,500 psi f’c = 3,000 psi f’c = 4,000 psi f’c = 6,000 psi f’c = 8,000 psi
f
N
n
Tension
(lbs.)
f
V
sn
Shear
(lbs.)
f
N
n
Tension
(lbs.)
f
V
sn
Shear
(lbs.)
f
N
n
Tension
(lbs.)
f
V
sn
Shear
(lbs.)
f
N
n
Tension
(lbs.)
f
V
sn
Shear
(lbs.)
f
N
n
Tension
(lbs.)
f
V
sn
Shear
(lbs.)
1/4
1-5/8 495 370 525 405 575 470 645 575 705 660
2-1/2 920 450 970 495 1,060 570 1,195 700 1,305 810
3/8
2 785 445 860 485 990 560 1,215 685 1,405 790
2-1/2 1,115 500 1,220 550 1,410 635 1,725 775 1,995 895
3-1/4 1,685 595 1,845 650 2,130 755 2,610 920 3,015 1,065
1/2
2-1/2 1,070 675 1,170 740 1,355 855 1,655 1,045 1,915 1,205
3 1,520 760 1,665 835 1,925 960 2,355 1,180 2,720 1,360
4-1/4 2,595 935 2,840 1,025 3,280 1,180 4,015 1,445 4,640 1,670
5/8
3-1/4 1,585 800 1,735 875 2,005 1,010 2,455 1,240 2,835 1,430
4 2,220 920 2,430 1,010 2,805 1,165 3,435 1,425 3,970 1,645
5 3,160 1,045 3,460 1,145 3,995 1,325 4,895 1,620 5,650 1,870
3/4 4-1/4 2,430 985 2,660 1,080 3,075 1,245 3,765 1,525 4,345 1,760
■ - Anchor Pullout/Pryout Strength Controls ■ - Concrete Breakout Strength Controls ■ - Steel Strength Controls
Tension and Shear Design Strength at Minimum Edge Distance, c
min
for Screw-Bolt+ in Uncracked Concrete
Nominal
Anchor
Diameter
(in.)
Nominal
Embed.
h
nom
(in.)
Minimum Concrete Compressive Strength
f’c = 2,500 psi f’c = 3,000 psi f’c = 4,000 psi f’c = 6,000 psi f’c = 8,000 psi
f
N
n
Tension
(lbs.)
f
V
sn
Shear
(lbs.)
f
N
n
Tension
(lbs.)
f
V
sn
Shear
(lbs.)
f
N
n
Tension
(lbs.)
f
V
sn
Shear
(lbs.)
f
N
n
Tension
(lbs.)
f
V
sn
Shear
(lbs.)
f
N
n
Tension
(lbs.)
f
V
sn
Shear
(lbs.)
1/4
1-5/8 460 495 505 540 580 625 710 765 820 885
2-1/2 860 635 940 695 1,085 800 1,330 980 1,535 1,130
3/8
2 550 595 605 650 700 750 855 920 990 1,065
2-1/2 655 700 720 765 830 885 1,015 1,085 1,175 1,250
3-1/4 1,095 835 1,200 915 1,385 1,055 1,695 1,290 1,955 1,490
1/2
2-1/2 1,615 945 1,770 1,035 2,045 1,195 2,505 1,465 2,890 1,690
3 1,185 1,065 1,300 1,165 1,500 1,345 1,835 1,650 2,120 1,905
4-1/4 2,190 1,310 2,400 1,430 2,770 1,655 3,390 2,025 3,915 2,340
5/8
3-1/4 1,495 1,120 1,635 1,225 1,890 1,415 2,310 1,735 2,670 2,000
4 1,715 1,290 1,875 1,410 2,165 1,630 2,655 1,995 3,065 2,305
5 2,470 1,465 2,705 1,605 3,125 1,855 3,830 2,270 4,420 2,620
3/4 4-1/4 1,635 1,380 1,790 1,510 2,070 1,745 2,535 2,135 2,925 2,465
■ - Anchor Pullout/Pryout Strength Controls ■ - Concrete Breakout Strength Controls ■ - Steel Strength Controls