2.0 SHEAR
2.3 Steel Failure Mode
Equations A Na0
Equations ACI 318-19 Chapter 17 Provision Comments for PROFIS Engineering
A Na0
= ( 2c Na
) 2
17.6.5.1.2 A Na0 is the projected influence area of a single adhesive anchor with an edge distance of at least c Na . where
A Na0
= ( 2c Na ) 2 ( 17.6.5.1.2a ) c Na
= 10d a т uncr ( 17.6.5.1.2b ) 1100
When calculating the nominal concrete pryout strength in shear ( V cp or V cpg
), the parameter A Na0 is a modification factor that accounts for the area of influence assumed to develop in concrete when a shear load applied to a single anchor without the influence of any fixed edges creates a prying ( i . e . tension ) action on the anchor . A Na0 is calculated with the parameter “ c Na
”, which is defined in ACI 318-19 Chapter 2 as the “ projected distance from center of an anchor shaft on one side of the anchor required to develop the full bond strength of a single adhesive anchor ”. The geometry for A Na0 is defined by a projected distance of c Na from the anchor in the x and y directions .
The figure below illustrates how A Na0 is calculated .
17.6.5.1 Nominal bond strength in tension , N a of a single adhesive anchor or N ag of an adhesive anchor group satisfying 17.5.1.3.1 , shall be calculated by ( a ) or ( b ), respectively . ( a ) For a single adhesive anchor
|
N a
=
A
|
Na ψ ed , Na ψ cp , Na
N ba
|
( 17.6.5.1a ) |
|
A Na0
|
|
( b ) For an adhesive anchor group
N ag
= A Na ψ ec , Na ψ ed , Na ψ cp , Na
N ba
( 17.6.5.1b )
A Na0
………………………………………………………
A Na0
= ( c Na + c Na
) ( c Na + c Na
)
= ( 2.0 c Na
) 2
Reference the Calculations section of the PROFIS Engineering report for more information on c Na and A Na0
.
247 NORTH AMERICAN PROFIS ENGINEERING ANCHORING TO CONCRETE DESIGN GUIDE — ACI 318-19 Provisions