PROFIS Design Guide - AC 318-19 July 2022 | Page 302

2.0 SHEAR

2.4 Stand-off Failure Mode
Results ϕ eb
Results ACI 318-19 Chapter 17 Provision Comments for PROFIS Engineering
ϕ eb
17.7.1.1 Nominal steel strength of anchors in shear as governed by the steel , V sa
, shall be evaluated based on the properties of the anchor material and the physical dimensions of the anchors . If concrete breakout is a potential failure mode , the required steel shear strength shall be consistent with the assumed breakout surface .
17.7.1.2 Nominal strength of an anchor in shear , V sa
, shall not exceed ( a ) through ( c ): …………………………………………………..
( 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
= 0.6A se , V ƒ uta
( 17.7.1.2b ) where A se , V is the effective cross-sectional area of an anchor in shear , in . 2 , and the value of ƒ uta shall not exceed either 1.9ƒ ya or 125,000 psi .
ACI 318-19 Section 17.7.1.2 contains provisions for calculating the nominal steel strength of an anchor in shear ( V sa
). Section 17.7.1.2.1 requires the value for V sa to be multiplied by a 0.80 reduction factor if the anchor application consists of a grouted stand-off . This reduction factor is only relevant with respect to ACI 318 anchoring-to-concrete provisions when a grouted stand-off is being designed , i . e ., no guidance or provisions are given in ACI 318 for stand-off applications that are not grouted . PROFIS Engineering designates this 0.8-factor “ ϕ eb
”.
PROFIS Engineering also includes functionality to consider anchor bending when modelling non-grouted stand-offs subject to shear load . This functionality is explained in the Design Guide section for “ steel failure with lever arm ”.
Reference the Results section of the PROFIS Engineering report for more information on the parameters ϕV sa and ϕV sa , eq .
( c ) For post-installed anchors where sleeves extend through the shear plane , V sa shall be based on the 5 percent fractile of results of tests performed and evaluated in accordance with ACI 355.2 . Alternatively , Eq . ( 17.7.1.2b ) shall be permitted to be used .
17.7.1.2.1 If anchors are used with built-up grout pads , nominal strength V sa calculated in accordance with 17.7.1.2 shall be multiplied by 0.80 .
302 NORTH AMERICAN PROFIS ENGINEERING ANCHORING TO CONCRETE DESIGN GUIDE — ACI 318-19 Provisions