2.0 SHEAR
2.2 Pryout Failure Mode
Variables ƒ ́c
Variables ACI 318-19 Chapter 17 Provision Comments for PROFIS Engineering
ƒ ́c
17.3.1 The value of ƒ ́c used for calculation purposes in this chapter shall not exceed 10,000 psi for cast-in anchors , and 8000 psi for post-installed anchors . Post-installed anchors shall not be used in concrete with a strength greater than 8000 psi without testing to verify acceptable performance .
17.6.2.2.1 Basic concrete breakout strength of a single anchor in tension in cracked concrete , N b , shall be calculated by Eq . ( 17.6.2.2.1 ), except as permitted in 17.6.2.2.3
N b
= k c λ a ƒ ́c h ef
1.5
( 17.6.2.2.1 )
17.6.2.2.3 For single cast-in headed studs and headed bolts with 11 in . ≤ h ef ≤ 25 in ., N b
, shall be calculated by :
N b
= 16λ a ƒ ́c h ef
5 / 3
( 17.6.2.2.3 )
When calculating nominal concrete pryout strength in shear ( V cp or V cpg
), ƒ ́c is a parameter used to define concrete compressive strength . This parameter is used to calculate the parameter “ N b
”, which is used to calculate a concrete breakout strength ( N cb or N cbg
).
Post-installed mechanical anchors can be qualified for recognition under the International Building Code via testing per the ICC-ES acceptance criteria AC193 in conjunction with the ACI standard ACI 355.2 . Post-installed adhesive anchor systems can be qualified for recognition under the International Building Code via testing per the ICC-ES acceptance criteria AC308 in conjunction with the ACI standard ACI 355.4 . ƒ ́c provisions for a specific post-installed anchor are derived from this testing and will be given in the ICC-ES evaluation report ( ESR ) for the anchor . PROFIS Engineering uses these ƒ ́c provisions for post-installed anchor design . The post-installed anchor portfolio in PROFIS Engineering is limited to installation in concrete having a specified compressive strength between 2500 psi and 8500 psi , and design using an ƒ ́c-value less than or equal to 8000 psi . Reference the ESR for ƒ ́c information specific to a post-installed anchor .
PROFIS Engineering users can input an ƒ ́c-value within the range 2500 psi ≤ ƒ ́c ≤ 8500 psi for post-installed anchor design . The maximum ƒ ́c-value for calculations will be limited to 8000 psi .
PROFIS Engineering users can input an ƒ ́c-value within the range 2500 psi ≤ ƒ ́c ≤ 10,000 psi for cast-in-place anchor design . The maximum ƒ ́c-value for calculations will be limited to 10,000 psi .
Reference the Equations and Calculations sections of the PROFIS Engineering report for more information on the parameter N b
.
226 NORTH AMERICAN PROFIS ENGINEERING ANCHORING TO CONCRETE DESIGN GUIDE — ACI 318-19 Provisions