PART 3 TENSION LOAD
Concrete Breakout Failure Mode
Equation N cbg
Equation ACI 318-14 Chapter 17 Provision Comments for PROFIS Engineering
N cbg
= A Nc ψ ec , N ψ ed , N ψ c , N ψ cp , N
A Nc0
17.4 . 2.1 The nominal concrete breakout strength in tension , …….. N cbg of a group of anchors , shall not exceed : ( b ) For a group of anchors
N cbg
= A Nc ψ ec , N ψ ed , N ψ c , N ψ cp , N
N b
( 17.4.2.1b )
A Nc0
Reference the Calculations section of the PROFIS Engineering report for more information on the following parameters :
A Nc
: Area of influence for anchors in tension
A Nc0
: Area of influence for single anchor in tension
ψ ec , N
: Tension modification factor for eccentricity
ψ ed , N
: Tension modification factor for edge distance
ψ cp , N
: Modification factor for splitting
N b
: Basic concrete breakout strength in tension
Reference the Variables section of the PROFIS Engineering report for information on : ψ c , N
: Modification factor for cracked concrete
Equation ϕN cb
Equation ACI 318-14 Chapter 17 Provision Comments for PROFIS Engineering
ϕN cb
≥ N 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 Concrete Breakout Strength in Tension
Anchors as a Group
ϕN cbg
> N ua
ACI 318-14 strength design provisions for tension check a calculated design strength ( ϕN N
) against a factored tension load ( N ua
).
Reference the Results section of the PROFIS Engineering report for more information on the following parameters :
N cbg
: Nominal concrete breakout strength in tension
ϕ concrete
: Strength reduction factor for concrete failure
ϕ seismic
: Strength reduction factor for seismic tension
ϕN cbg
: Design concrete breakout strength in tension
N ua
: Factored load acting on anchors in tension
A summary of calculated tension design strength versus the factored tension load for each tension failure mode relevant to the application is given in Part 3 Tension Load of the PROFIS Engineering report .
49 NORTH AMERICAN PROFIS ENGINEERING ANCHORING TO CONCRETE DESIGN GUIDE — ACI 318-14 Provisions