PART 4 SHEAR LOAD
Stand-off Failure Mode
Equations
S = π ( d ) 3 32
Equations 318-14 Chapter 17 Provision Comments for PROFIS Engineering
S = π ( d ) 3 32
2.3 Concrete and steel
W el
= elastic section modulus calculated from the stressed cross section of steel ( πd 3 / 32 for a round section with diameter d )
5.2.3.2 Steel failure b ) Shear load with lever arm
characteristic flexural resistance of anchor
The characteristic bending resistance M 0 is given in the relevant ETA .
Rk , s
The value of M 0 for anchors according to current experience is obtained from Equation ( 5 . 5b ).
Rk , s
M 0 Rk , s = 1 . 2W el f u , k
[ Nm ] ( 5 . 5b )
Equation ( 5.5b ) may be used only if the anchor has not a significantly reduced section along the length of the bolt .
5.2.3.2 Steel failure b ) Shear load with lever arm
The characteristic resistance of an anchor , V Rk , s , is given by Equation ( 5.5 ). where
V Rk , s
= α M M Rk , s [ N ] ( 5.5 ) l α M
= see 4.2.2.4 l = lever arm according to Equation ( 4.2 )
M Rk , s
= M 0 ( 1 - N / N ) [ Nm ] ( 5 . 5a )
Rk , s Sd Rd , s
N Rd , s
= NRk , s / γMs
N Rk , s
, γ Ms to be taken from the relevant ETA M 0 = characteristic bending resistance of an individual anchor
Rk , s
PROFIS Engineering uses the provisions given in the European Technical Approval Guideline ( ETAG ) titled ETAG 001 Metal Anchors for Use in Concrete Annex C : Design Methods for Anchorages to consider bolt bending as a possible shear failure mode .
The ETAG 001 parameter M 0 corresponding to the “ characteristic bending
Rk , s resistance ” of the anchor is defined by Equation ( 5.5b ) as shown to the left . The parameter W el corresponds to the “ elastic section modulus ” of the anchor element . The PROFIS Engineering report designates the parameter “ M 0 ” Rk , s as “ M 0 ” and the elastic section modulus for the anchor element as “ S ”. s
The “ characteristic bending resistance ” of the anchor is defined in PROFIS Engineering by the equation :
M 0 s = ( 1 . 2 ) ( S ) ( f u , min ) where “ f u , min
” corresponds to the “ minimum specified ultimate tensile strength ” of the anchor element . PROFIS Engineering uses this equation to calculate M 0 for all s of the cast in and post-installed anchors in its portfolio . PROFIS Engineering calculates the section modulus ( S ) as follows : cast-in anchor
post-installed anchor
S = [( π ) ( d minor
) 3 ]/ 32
calculate d using the tensile stress area of the anchor element ( A se ).
Values for A se are given in the ICC-ESR for the anchor product .
d Ase
= [( 4 )( A se )/ π ] 0 . 5
S = [( π ) ( d Ase
) 3 ]/ 32
Reference the Equations and Calculations section of the report for more information on the following PROFIS Engineering parameter .
M 0 : Characteristic flexural resistance of the anchor element s
321 NORTH AMERICAN PROFIS ENGINEERING ANCHORING TO CONCRETE DESIGN GUIDE — ACI 318-14 Provisions