1.0 TENSION
1.3 Pullout Failure Mode
Calculations N p
Calculations ACI 318-19 Chapter 17 Provision Comments for PROFIS Engineering cast-in anchors
N p
17.6.3.1 Nominal pullout strength of a single cast-in anchor , or a single post-installed expansion , screw , or undercut anchor in tension , N pn
, shall be calculated by :
N pn
= ψ c , p
N p
( 17.6.3.1 ) ………………………………………
17.6.3.2.2 For single anchors , it shall be permitted to evaluate the pullout strength in tension ,
N p
, for use in Eq . ( 17.6.3.1 ) in accordance with ( a ) or ( b ). Alternatively , it shall be permitted to use values of N p based on the 5 percent fractile of tests performed and evaluated in the same manner as the ACI 355.2 . procedures but without benefit of friction .
( a ) For cast-in headed studs and headed bolts , N p shall be calculated by :
N p
= 8A brg ƒ ́c ( 17.6.3.2.2a )
( b ) For J- or L-bolts , N p shall be calculated by :
N p
= 0.9 ƒ ́c e h d a
( 17.6.3.2.2b ) where 3d a ≤ e h
≤ 4.5d a
.
Profis Engineering cast-in anchor portfolios for bearing area ( A brg ).
MATERIAL SPECIFICATION
AWS D1.1 Type B Headed Stud
ASTM F1554 Headed Bolt Gr . 36 , Gr . 55 , Gr . 105
Diameter ( d 0
) ( in )
Bearing area ( A brg in 2 ) Welded headed stud
Bearing area ( A brg in 2 ) Square head bolt
Bearing area ( A brg in 2 ) Heavy square bolt
Bearing area ( A brg in 2 ) Hex head bolt
Bearing area ( A brg in 2 ) Heavy hex head bolt
0.500 |
0.589 |
0.625 |
0.920 |
0.750 |
0.785 |
0.875 |
0.884 |
0.500 |
0.464 |
0.569 |
0.291 |
0.467 |
0.625 |
0.693 |
0.822 |
0.454 |
0.671 |
0.750 |
0.824 |
1.210 |
0.654 |
0.911 |
0.875 |
1.121 |
1.465 |
0.891 |
1.188 |
1.000 |
1.465 |
1.855 |
1.163 |
1.501 |
1.125 |
1.854 |
2.291 |
1.472 |
1.851 |
1.250 |
2.228 |
2.773 |
1.817 |
2.237 |
1.375 |
2.769 |
3.300 |
2.199 |
2.659 |
1.500 |
3.295 |
3.873 |
2.617 |
3.118 |
1.750 |
|
|
|
4.144 |
2.000 |
|
|
|
5.316 |
The parameter “ N p
” in Eq . ( 17.6.3.1 ) is defined as the “ pullout strength in tension ” for a single anchor . PROFIS Engineering calculates N p per Eq . ( 17.6.3.2.2a ) for the cast-in anchors in its portfolio . The PROFIS Engineering cast-in-place anchor portfolio is as follows :
• AWS D1.1 Type B headed studs ( 1 / 2 ” — 7 / 8 ” nominal diameter )
• ASTM F1554 hex head bolt , Gr . 36 , Gr . 55 , Gr . 105 ( 1 / 2 ” — 1-1 / 2 ” nominal diameter )
• ASTM F1554 heavy hex head bolt , Gr . 36 , Gr . 55 , Gr . 105 ( 1 / 2 ” — 2 ” nominal diameter )
• ASTM F1554 square head bolt , Gr . 36 , Gr . 55 , Gr . 105 ( 1 / 2 ” — 1-1 / 2 ” nominal diameter )
• ASTM F1554 heavy square head bolt , Gr . 36 , Gr . 55 , Gr . 105 ( 1 / 2 ” — 1-1 / 2 ” nominal diameter )
Bearing area values ( A brg
) for these anchors are shown in the table to the left . Cast-in J-bolts and L-bolts are not included in the PROFIS Engineering cast-in anchor portfolio . PROFIS Engineering only calculates N p per Eq . ( 17.6.3.2.2a ) for cast-in anchors . N p for post-installed anchors is derived from testing .
Reference the Equations section of the report for more information on the parameter N p
.
Reference the Variables section of the report for more information on the following parameters :
• A brg
— bearing area for a cast-in anchor .
• ƒ ́c — concrete compressive strength .
PROFIS Engineering does not calculate N p per Eq . ( 17.6.3.2.2a ) for the postinstalled anchors in its portfolio . N p
-values are derived from product-specific testing . Reference the post-installed anchor report sections relevant to pullout strength in tension for more information .
94 NORTH AMERICAN PROFIS ENGINEERING ANCHORING TO CONCRETE DESIGN GUIDE — ACI 318-19 Provisions