PART 4 SHEAR LOAD
Steel Failure Mode
Variables f uta
Variables 318-14 Chapter 17 Provision Comments for PROFIS Engineering
f uta
17.5.1.1 The nominal strength of an anchor in shear as governed by steel , V sa
, shall be evaluated by calculations based on the properties of the anchor material and the physical dimensions of the anchor . Where concrete breakout is a potential failure mode , the required steel shear strength shall be consistent with the assumed breakout surface .
17.5.1.2 The nominal strength of an anchor in shear , V sa , shall not exceed ( a ) through ( c ):
( a ) For cast-in headed stud anchor
V sa
= A se , V f uta
( 17.5.1.2a ) where A se , V is the effective cross-sectional area of an anchor in shear , in . 2 , and f uta shall not be taken greater than the smaller of 1.9fy a and 125,000 psi .
b ) For cast-in headed bolt and hooked bolt anchors and for post-installed anchors where sleeves do not extend through the shear plane
V sa
= 0.6 A se , V f uta
( 17.5.1.2b ) where A se , V is the effective cross-sectional area of an anchor in shear , in . 2 , and f uta shall not be taken greater than the smaller of 1.9fy a and 125,000 psi . ( c ) For post-installed anchors where sleeves extend through the shear plane , V sa shall be based on the results of tests performed and evaluated according to ACI 355.2 . Alternatively , Eq . ( 17.5.1.2b ) shall be permitted to be used .
PROFIS Engineering cast-in anchor portfolio values for A se , v and f uta
.
MATERIAL SPECIFICATION
AWS D1.1
ASTM F 1554
ASTM F 1554
ASTM F 1554
GRADE OR TYPE
DIAMETER ( d 0
) ( in )
TENSILE STRENGTH ( f uta
)
( ksi )
YIELD STRENGTH ( f ya
)
( ksi )
GROSS AREA ( in 2 )
EFFECTIVE AREA ( A se
)
( in 2 )
B |
0.500 |
65 |
51 |
0.196 |
|
B |
0.625 |
65 |
51 |
0.307 |
|
B |
0.750 |
65 |
51 |
0.442 |
|
B |
0.875 |
65 |
51 |
0.601 |
|
36 |
0.500 |
58 |
36 |
0.196 |
0.142 |
36 |
0.625 |
58 |
36 |
0.307 |
0.226 |
36 |
0.750 |
58 |
36 |
0.442 |
0.334 |
36 |
0.875 |
58 |
36 |
0.601 |
0.462 |
36 |
1.000 |
58 |
36 |
0.785 |
0.606 |
36 |
1.125 |
58 |
36 |
0.994 |
0.763 |
36 |
1.250 |
58 |
36 |
1.227 |
0.969 |
36 |
1.375 |
58 |
36 |
1.485 |
1.160 |
36 |
1.500 |
58 |
36 |
1.767 |
1.410 |
36 |
1.750 |
58 |
36 |
2.405 |
1.900 |
36 |
2.000 |
58 |
36 |
3.142 |
2.500 |
55 |
0.500 |
75 |
55 |
0.196 |
0.142 |
55 |
0.625 |
75 |
55 |
0.307 |
0.226 |
55 |
0.750 |
75 |
55 |
0.442 |
0.334 |
55 |
0.875 |
75 |
55 |
0.601 |
0.462 |
55 |
1.000 |
75 |
55 |
0.785 |
0.606 |
55 |
1.125 |
75 |
55 |
0.994 |
0.763 |
55 |
1.250 |
75 |
55 |
1.227 |
0.969 |
55 |
1.375 |
75 |
55 |
1.485 |
1.160 |
55 |
1.500 |
75 |
55 |
1.767 |
1.410 |
55 |
1.750 |
75 |
55 |
2.405 |
1.900 |
55 |
2.000 |
75 |
55 |
3.142 |
2.500 |
105 |
0.500 |
125 |
105 |
0.196 |
0.142 |
105 |
0.625 |
125 |
105 |
0.307 |
0.226 |
105 |
0.750 |
125 |
105 |
0.442 |
0.334 |
105 |
0.875 |
125 |
105 |
0.601 |
0.462 |
105 |
1.000 |
125 |
105 |
0.785 |
0.606 |
105 |
1.125 |
125 |
105 |
0.994 |
0.763 |
105 |
1.250 |
125 |
105 |
1.227 |
0.969 |
105 |
1.375 |
125 |
105 |
1.485 |
1.160 |
105 |
1.500 |
125 |
105 |
1.767 |
1.410 |
105 |
1.750 |
125 |
105 |
2.405 |
1.900 |
105 |
2.000 |
125 |
105 |
3.142 |
2.500 |
ACI 318-14 Equation 17.5.1.2 includes the parameter f uta to calculate the nominal steel strength in shear ( V sa ). ACI 318-14 Chapter 2 defines f uta as the “ specified tensile strength of anchor steel ”. ICC-ESR for post-installed anchors include values for the “ minimum specified ultimate strength ”. Unlike reinforced concrete design , which uses bar yield strength ( f y
) for shear calculations ; ACI 318 anchoring-to-concrete provisions use the ultimate tensile strength of an anchor element ( f uta
) to calculate the nominal steel strength in shear ( V sa ). The ACI 318-14 commentary R17.5.1.2 notes :
“ The nominal shear strength of anchors is best represented as a function of f uta rather than f ya because the large majority of anchor materials do not exhibit a well-defined yield point ”.
The PROFIS Engineering cast-in-place anchor portfolio includes the following anchors :
• 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 )
The table to the left shows the f ya and f uta values for the PROFIS Engineering castin-place anchor portfolio . PROFIS Engineering uses the f uta values to calculate V sa per Section 17.5.1.2 .
Post-installed anchor ICC-ESR include pre-calculated values for the nominal static shear steel strength of an anchor element ( V sa
), and nominal seismic shear steel strength of an anchor element ( V sa , eq ). A se , V and f uta values may also be given in the ICC-ESR ; however , PROFIS Engineering uses the pre-calculated V sa and
V sa
, eq values instead of calculating nominal steel strength in shear per Section 17.5.1.2 .
Reference the Calculations and Results section of the PROFIS Engineering report for more information on :
V sa
: Nominal ( static ) steel strength in shear
V sa , eq
: Nominal ( seismic ) steel strength in shear
Reference the Variables section of the PROFIS Engineering report for more information on :
A se , V
: Tensile stress area of an anchor element
301 NORTH AMERICAN PROFIS ENGINEERING ANCHORING TO CONCRETE DESIGN GUIDE — ACI 318-14 Provisions