PART 3 TENSION LOAD
Steel Failure
Equation N sa
Equation ACI 318-14 Chapter 17 Provision Comments for PROFIS Engineering
N sa
17.4.1.1 The nominal strength of an anchor in tension as governed by the steel , N sa
, shall be evaluated by calculations based on the properties of the anchor material and the physical dimensions of the anchor .
17.4.1.2 The nominal strength of an anchor in tension , N sa , shall not exceed
N sa
= A se , N
F uta
( 17.4.1.2 )
Where A se , N is the effective cross-sectional area of an anchor in tension , in . 2 , and f uta shall not be taken greater than the smaller of 1.9 f ya and 125,000 psi . PROFIS Engineering cast-in-place anchor portfolio parameters used to calculate N sa
.
MATERIAL SPECIFICATION
AES 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 |
Excerpt from a mechanical anchor ICC-ESR showing the parameter N sa .
Excerpt from an adhesive anchor ICC-ESR showing the parameter N sa .
ACI 318-14 Chapter 2 defines the parameter N sa as follows :
“ nominal strength of a single anchor or individual anchor in a group of anchors in tension as governed by the steel strength ”.
N sa is always calculated for a single anchor when designing with the provisions of ACI 318-14 .
For cast-in-place anchors , PROFIS Engineering calculates N sa using Equation ( 17.4.1.2 ). The table to the left shows the cast-in-place anchor portfolio in PROFIS Engineering , and the parameters that are used to calculate N sa for a given anchor type and diameter .
Post-installed mechanical anchors can be shown compliance under the International Building Code ( IBC ) via testing per the ICC-ES acceptance criteria AC193 and the ACI test standard ACI 355.2 . Data derived from this testing is given in an ICC-ESR . Pre-calculated values for N sa are given in mechanical anchor ICC-ESR design tables . Although parameters such as A se and f uta may be given in the ICC-ESR , PROFIS Engineering uses the pre-calculated N sa -values to define the nominal steel strength in tension . The parameter “ N sa
” in the Equations section of the PROFIS Engineering report references the “ ESR value ” in lieu of Equation ( 17.4.1.2 ). An excerpt from a mechanical anchor ESR showing N sa
-values derived from AC193 / ACI 355.2 testing is referenced to the left .
Post-installed adhesive anchor systems can be shown compliance under the IBC via testing per the ICC-ES acceptance criteria AC308 and the ACI test standard ACI 355.4 . Data derived from this testing is given in the adhesive anchor ICC- ESR . Pre-calculated values for N sa are given in adhesive anchor ICC-ESR design tables . Parameters such as A se and f uta may be given in the ICC-ESR , but PROFIS Engineering uses the pre-calculated N sa
-values specific to the anchor element that is being modeled to define the nominal steel strength in tension . The PROFIS Engineering adhesive anchor portfolio includes the following anchor elements :
• Threaded rods
• Reinforcing bars
• Internally threaded inserts
• Proprietary elements
Reference the adhesive anchor system ICC-ESR for N sa values specific to an anchor element . The parameter “ N sa
” in the Equations section of the PROFIS Engineering report references the “ ICC-ESR value ” in lieu of Equation ( 17.4.1.2 ). An excerpt from an adhesive anchor ICC-ESR showing N sa
-values derived from AC308 / ACI 355.4 testing is referenced to the left .
Reference the Calculations and Results section of the report for more information on N sa
.
Reference the Variables section of the report for more information on the parameters A se , N and f uta
.
130 NORTH AMERICAN PROFIS ENGINEERING ANCHORING TO CONCRETE DESIGN GUIDE — ACI 318-14 Provisions