1. Anchor
Channel Systems
Code
2. HAC
Portfolio
3. HAC
Applications
4. Design
Introduction
Discussion
5. Base material
6. Loading
Calculations
Step 7: Concrete strength
ESR-3520 section
4.1.3.3.3
ACI 318-14 Chapter 17
The calculated φV cb,3 value for anchor element #3 will be checked against the factored
load acting on anchor element #3 (V aua,3 ) to obtain the % utilization (V aua,3 / φV cb3 ).
The anchor element with the highest % utilization will control the design with respect
to concrete breakout failure in tension.
φ-factors for concrete breakout in tension are given in ESR-3520 Table 8-4.
ɸ factor:
ACI 318-14:
17.3.3 Strength reduction factor ϕ for anchors in concrete shall be as follows when the
load combinations of 5.3 are used:
(c) Anchor governed by concrete breakout, side-face, blowout, pullout, or pryout
strength
8. Reinforcing
Bar Anchorage
Code
9. Special Anchor
Channel Design
10. Design
Software
11. Best
Practices
12. Instructions
for Use
Discussion
13. Field Fixes
14. Design
Example
Calculations
Step 7: Concrete strength
Concrete breakout strength in perpendicular shear for anchor element #3 continued...
Nominal concrete breakout strength in tension for anchor element #3
ESR-3520 Equation (6)
The calculated value for V cb,3 will be multiplied by a strength reduction factor (φ-factor)
to give a design strength (φV cb,3 ). Design strengths for this example are summarized in
the table on this page titled Summary for Concrete Breakout in Tension.
7. Anchor Channel
Design Code
ESR-3520 section
4.1.3.2.2
Concrete failure modes of anchor channels under combined loads:
ESR 3520 sec tion 4.1.3.6.3 b) If N a ua < 0.2 f N nc then the full strength in shear shall be
a
æ V ua,y
permitted : ç
ç j V nc,y
è
a
ö
æ V ua,x
÷ ÷ + ç ç
j
V
nc,x
è
ø
ö
÷ ÷ £ 1.0
ø
Concrete edge breakout: ФV cb,y
V cb,3 = V b,3 × ψ s,V,3 × ψ co1,V,3 × ψ co2,V,3 × ψ h,V,3 × ψ c,V,3
V b,3 = 6954 lbs
ψ s,v = 0.598
β cb,N,3 = 0.17 < 0.2
β cb,V,3 = 0.87 < 1.0
\ Concrete utilization = 87%
ψ co1,v = 0.774
ψ co2,v = 1.0
ψ c,v = 1.2
ψ h,v = 0.694
V cb , y , 3 = 2681 lbs
Condition B
Condition A
• Supplementary reinforcement is present
• Reinforcement does not need to be explicitly designed for the anchor channel
• Should generally conform to reinforcement shown in Fig. R17.4.2.9 and R17.5.2.9b
• Full development is not required
j = 0.7
j V cb,y,3 = 1876lbs
V a ua,3 = 1618 lbs
æ 1618 ö
÷ x 100
è 1876 ø
b cb , v , 3 = 87%
b cb , 3 = ç
Condition B
No supplementary reinforcement
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Cast-In Anchor Channel Product Guide, Edition 1 • 02/2019
411