Product Technical Guides : US-EN Cast-In Anchor Channel Fastening Technical Guide | Page 258

1. Anchor Channel Systems 2. HAC Portfolio 3. HAC Applications 4. Design Introduction 5. Base material 6. Loading 7. Anchor Channel Design Code 8. Reinforcing Bar Anchorage 9. Special Anchor Channel Design 10. Design Software Longitudinal shear Both the front and back anchor channels are analyzed in tension using an imaginary concrete edge of x/2 as shown in Figure 9.2.13.7, if both anchor channels are equally loaded. The longitudinal shear force V ua,x is applied at an eccentricity, as shown in Figure 9.2.13.10. This eccentricity creates the force V uax,b on anchor channel b in opposite to the direction of V ua,x . Where as anchor channel a experiences the longitudinal force in the direction of V ua,x . Having infinite sides edges on both sides will create breakout planes perpendicular to the edge as seen in the Figure 9.2.13.10. For analyzing anchor channel a the front edge of c a1 ,a is considered. For analyzing anchor channel b the edge available in between the two channels is used, which is x (c a1,b - c a1,a ) as shown in Figure 9.2.13.10. Please note that the location of imaginary concrete edge can be optimized according to the magnitude of tensile forces each anchor channel is experiencing as shown in Figure 9.2.13.8. The imaginary edge is assumed at a distance of (3/4)x from the back channel, if the back channel is experiencing a larger tension force. 13. Field Fixes 14. Design Example Figure 9.2.13.7 — Tension -Equal tension force-Section view. Alternatively, the spacing method can be used to determine the spacing modification factor ψ s,N for the anchor in consideration, considering the effect of the anchors of the channel parallel to the one in consideration. Please note that there is no need to assume the imaginary edge in between the channel when spacing method is used. The actual perpendicular edge distance of the channel has to be consider, while calculating the edge modification factor ψ ed,N . Refer Figure 9.2.13.8. 12. Instructions for Use Tension 11. Best Practices Please refer to the formula below for finding the spacing modification factor for anchor a 1 of channel a. y s,N,a1 = 1 1.5 1.5 1.5 a é æ s ù é ù ö N æ s ö N a ù é æ s ö N a 1 + ê ç ç 1 - a1,a2 ÷ ÷ × a ua,a2 ú + ê ç ç 1 - a1,b1 ÷ ÷ × a ua,b1 ú ê ç ç 1 - a1,b2 ÷ ÷ × a ua,b2 ú ê è s cr,N ø N ua,a1 ú ê è s cr,N ø N ua,a1 ú ê è s cr,N ø N ua,a1 ú ë û ë ûë û The edge modification factor for anchor channel a is given below. Figure 9.2.13.8 — Tension — unequal tension force-Section view. c a 1, a £ C Cr , N then Y ed , N æ c ö = ç a 1, a ÷ è C cr , N ø 0.5 Figure 9.2.13.10 — Longitudinal Shear — Plan view. æ c ö c a 1, b £ C Cr , N then Y ed , N = ç a 1, b ÷ è C cr , N ø The edge modification factor for anchor channel b is given below. 0.5 Figure 9.2.13.9 — Tension — Equal tension force-Plan`` view. 258 Cast-In Anchor Channel Product Guide, Edition 1 • 02/2019 259