Product Technical Guides : US-EN Cast-In Anchor Channel Fastening Technical Guide | Page 408

1. Anchor Channel Systems Code 2. HAC Portfolio 3. HAC Applications 4. Design Introduction Discussion 5. Base material Calculations 8. Reinforcing Bar Anchorage 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... ESR-3520 section 4.1.3.3.3 ACI 318-14 Chapter 17 Calculate the modification factor for member thickness (ψ h,V,3 ). c a1 is measured perpendicular to the anchor channel longitudinal axis, and is considered when calculating the basic concrete breakout strength in shear (V b ) and the modification factor for member thickness (ψ h,V ). h 7. Anchor Channel Design Code Code Step 7: Concrete strength ESR-3520 Section 4.1.3.3.4. ACI 318-14 Chapter 17 6. Loading cr, V = 2c a1 + 2h ESR-3520 Equation (38) ch h ch … height of anchor channel b 1 ... Given in ICC-ESR alternatively a default value of 0.50 shall be used h ch … critical member thickness, y h, V æ h = ç ç è h cr, V ö ÷ ÷ ø b 1 Concrete edge breakout: ФV cb,y h cr,V = 2 (5.00 in) + 2 (1.22 in) h cr,V = 12.44 if h < h cr,V ESR-3520 Equation (37) y h, V Note: if cracked concrete conditions are assumed, and supplementary edge reinforcement as defined in ESR-3520 Section 4.1.3.3.3 is used, ψ c,V,3 can be increased to either ψ c,V,3 = 1.2 or ψ c,V,3 = 1.4. Cracked concrete No supplementary reinforcement ψ c,V = 1.0 With supplementary reinforcement • Cracked concrete with edge reinforcement (#4 min.) Concrete edge breakout: ФV cb,y If uncracked concrete conditions are assumed, ψ c,V,3 = 1.4. æ 6in ö ÷ è 12.44in ø = 0 . 694 £ 1.0 y h, V = ç £ 1.0 0 . 5 Concrete breakout strength in perpendicular shear for anchor element #3 continued... Calculate the modification factor for cracked/uncracked concrete (ψ c,V,3 ). Cracked concrete conditions with no supplementary reinforcement → ψ c,V,3 = 1.0 \ y h, V = 0 . 694 ψ c,V = 1.2 • Cracked concrete with edge reinforcement (#4 min.) and stirrups (#4 min.) spaced at 4” O.C. ψ c,V = 1.4 Uncracked Concrete Anchor channels located in a region of a concrete member where analysis indicates no cracking at service load levels. ψ c,V = 1.4 Note: in order to activate the reinforcement, concrete has to crack. Therefore, if uncracked concrete is assumed, supplementary reinforcement does not impact this factor. Concrete is typically assumed to be cracked under normal service load conditions. If cracked concrete conditions are assumed, an increase in V cb,y is permitted via the modification factor ψ c,V if supplementary edge reinforcement is used. If uncracked concrete conditions are assumed, an increase in V cb,y is likewise permitted via the modification factor ψ c,V . Reference ESR-3520 Section 4.1.3.3.3 for more information. Figure 14.1.24 — Design example – height reduction factor h cr,v 408 Cast-In Anchor Channel Product Guide, Edition 1 • 02/2019 409