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ψ ed , Na
= 0.7 + 0.3
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c a , min ≤ 1 . 0
c Na
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17.4.5.4 The modification factor for edge effects for single adhesive anchors or adhesive anchor groups loaded in tension , ψ ed , Na
, shall be calculated as
If c a , min ≥ c Na
, then ψ ed , Na = 1.0 ( 17.4.5.4a )
If c a , min < c Na
, then ψ ed , Na = 0.7 + 0.3
c a , min ( 17 . 4 . 5 . 4b )
c Na
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When calculating the nominal concrete pryout strength in shear ( V cp or V cpg
), the parameter ψ ed , Na is a modification factor that accounts for fixed edge distances less than c Na , where c Na corresponds to a calculated value representing a projected distance from the center of an adhesive anchor . The illustration below shows how the assumed area of influence with respect to pryout ( A Na
) would be defined for an anchoring application being modeled with two fixed edges ( c a1 and c a2
) that are both less than c Na , and with c a1 being less than c a2 . The smallest edge distance ( c a1 ) corresponds to the parameter c a , min
, and would be used to calculate the modification factor ψ ed , Na .
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17.4.5.1 …………………………………………………………… |
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c Na
= 10d a т uncr 17 . 4 . 5 . 1d 1100
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and the constant 1100 carries the unit of lb / in 2 . |
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ψ ed , Na
= 0.7 + 0.3 ( c a1 / c Na
)
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It is important to understand that “ ψ ed , Na ” calculated for bond failure in tension is not necessarily the same as “ ψ ed , Na
” calculated for concrete pryout failure in shear since the number of anchors in tension may not be the same as the number of anchors in shear .
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Reference the Variables section of the PROFIS Engineering report for more information on the following parameter : |
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c a , min
: Parameter for the smallest fixed edge being modeled
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Reference the Calculations section of the PROFIS Engineering report for more information on the following parameters : |
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c Na
: Edge distance parameter for adhesive anchors
|
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ψ ed , Na
: Modification factor for edge distance
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