PART 4 SHEAR LOAD
Stand-off Failure Mode
Equations ϕV s
M
≥ V ua
Equations 318-14 Chapter 17 Provision Comments for PROFIS Engineering
ϕV s
M
≥ V ua
17.3.1.1 The design of anchors shall be in accordance with Table 17.3.1.1 . In addition , the design of anchors shall satisfy 17.2.3 for earthquake loading and 17.3.1.2 for adhesive anchors subject to sustained tensile loading .
Table 17.3.1.1 Failure Mode Single Anchor Individual Anchor in a Group Steel Strength in Shear ϕ V sa
≥ V ua ϕ V sa
≥ V ua , i
ETAG 001 ANNEX C PROVISIONS FOR BENDING 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
ETAG 001 Equation ( 5.5 ) can be modified as follows using PROFIS Engineering nomenclature : nominal shear strength ( resistance ):
V s
M
= α M
M s
/ Lb design shear strength ( resistance ): ϕV s
M
= ϕ [ α M
M s
/ L b ] design check : ϕV s
M
≥ V ua
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 . ACI 318-14 strength design provisions for shear check a calculated design strength ( ϕV N
) against a factored shear load ( V ua
). The parameter “ design strength ” is defined as the product of a “ nominal strength ” ( V N
) and one or more strength reduction factors ( ϕ-factors ). If ϕV N ≥ V ua for all relevant shear failure modes , the ACI 318-14 shear provisions are satisfied .
PROFIS Engineering calculates a nominal steel strength ( V sM
) corresponding to the shear resistance in an anchor element when it is subjected to bending . PROFIS Engineering always calculates V s
M for a single anchor . If an application consists of a group of anchors in shear , V s
M is calculated for a single anchor , and the design strength ( ϕV sM
) is checked against the highest loaded anchor in shear . The nominal steel strength ( V sM
) is calculated using ETAG 001 provisions , and the design steel strength ( ϕV sM
) is calculated based on ACI 318-14 Section 17.3.1.1 . PROFIS Engineering designates the strength reduction factor for steel failure
ϕ steel
. When modeling cast-in anchors , PROFIS Engineering uses the ϕ-factors given in ACI 318-14 Section 17.2.3 ( a ) for the ϕ steel value . When modeling postinstalled anchors , PROFIS Engineering uses the ϕ-factors given in the anchor ICC-ESR for the ϕ steel value .
Reference the Results section of the PROFIS Engineering report for information on :
V sM
: Nominal steel strength in shear for bending
ϕV sM
: Design steel strength in shear for bending
ϕ steel
: Strength reduction factor for steel failure
V ua
: Factored load acting on anchors in shear
A summary of calculated shear design strength versus the factored shear load for each shear failure mode relevant to the application is given in Part 4 Shear Load of the PROFIS Engineering report .
324 NORTH AMERICAN PROFIS ENGINEERING ANCHORING TO CONCRETE DESIGN GUIDE — ACI 318-14 Provisions