PROFIS Design Guide - AC 318-19 July 2022 | Page 89

1.3 Pullout Failure Mode

Variables _{f ́c}

Variables ACI 318-19 Chapter 17 Provision Comments for PROFIS Engineering

_{f ́c} 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 . _{ƒ ́c} is a parameter used to define concrete compressive strength . This parameter is used to calculate the “ pullout strength in tension for a single anchor ” ( N _p

) per Eq . ( 17.6.3.2.2a ) for cast-in anchors , and the nominal pullout strength ( N _{p , f ́c}

) per

ESR provisions for post-installed mechanical anchors .

( 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 ) ………………………………………….

17.3.1 The value of _{f ́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 .

Excerpt from ESR-1917 for the Hilti Kwik Bolt-TZ ( KB-TZ ) expansion anchor referencing provisions for pullout strength in tension .

4.1.4 Requirements for Static Pullout Strength in Tension : The nominal pullout strength of a single anchor in accordance with ACI 318-14 17.4.3.1 and 17.4.3.2 or ACI 318-11 D . 5.3.1 and D . 5.3.2 , respectively , as applicable , in cracked and uncracked concrete ,

N _{p , cr} and N _{p , uncr} , respectively , is given in Tables 3 and 4 . For all design cases , ψ _{c , p}

= 1.0 . In accordance with ACI 318-14 17.4.3 or ACI 318-11 D . 5.3 , as applicable , the nominal pullout strength in cracked concrete may be calculated in accordance with the following equation :

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 . _{ƒ ́c} provisions for a specific postinstalled 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 anchor design . The maximum ^{ƒ ́c-value} for calculations will be limited to 10,000 psi .

N _{p , f ́c}

= N _{p , cr ƒ ́c} ( Eq-1 ) 2500

In regions where analysis indicates no cracking in accordance with ACI 318-14 17.4.3.6 or ACI 318-11 D . 5.3.6 , as applicable , the nominal pullout strength in tension may be calculated in accordance with the following equation :

N _{p , f ́c}

= N _{p , uncr ƒ ́c} ( Eq-2 ) 2500

Reference the Equations and Calculations sections of the PROFIS Engineering cast-in anchor report for more information on the parameter N _p

.

Reference the Equations and Calculations sections of the PROFIS Engineering mechanical anchor report for more information on the parameter N _{pn , ƒ ́c}

. The

PROFIS Engineering report designates the ESR parameter ” N _{p , f ́c} ” as “ N _{pn , ƒ ́c}

”.

Reference the Variables section of the PROFIS Engineering mechanical anchor report for more information on the parameter ( _{ƒ ́c} / 2500 ) ^{0 . 5} .

Where values for N _{p , cr} or N _{p , uncr} are not provided in Table 3 or Table 4 , the pullout strength in tension need not be evaluated . Excerpt from ESR-1917 showing values for N _{p , cr} and N _{p , uncr} derived from testing in 2500 psi concrete per AC193 / ACI 355.2 .

ICC-ES ESR-1917 Table 3

DESIGN INFORMATION

Effective min . embedment

Pullout strength uncracked concrete

Pullout strength cracked concrete

89 NORTH AMERICAN PROFIS ENGINEERING ANCHORING TO CONCRETE DESIGN GUIDE — ACI 318-19 Provisions