HAC_Technical-Guide

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Cast-In Anchor Channel Product Guide, Edition 1 • 02/2019
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
11. Best
Practices
12. Instructions
for Use
13. Field Fixes
14. Design
Example
9.1 Overview of Hilti Anchor Channel Systems Design
9.2 HAC and HAC-T Design 9.3 HAC CRFoS U Design 9.4 & 9.5 Post Tensioned Slabs 9.6 HAC EDGE Design
Figure 9.2.13.7 — Tension -Equal tension force-Section view.
Figure 9.2.13.8 — Tension — unequal tension force-Section view.
Figure 9.2.13.9 — Tension — Equal tension force-Plan`` view.
Tension
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.
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.
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.
Please refer to the formula below for finding the spacing
modification factor for anchor a
1
of channel a.
s,N,a1
1.5 1.5 1.5
a aa
a1,a2 ua,a2 a1,b1 ua,b1 a1,b2 ua,b2
a aa
cr,N ua,a1 cr,N ua,a1 cr,N ua,a1
1
sN sN sN
11 1 1
sN sN sN
y =
é ù é ùé ù
æö æö æö
ê ú ê úê ú
+ -×+ -× -×
ç÷ ç÷ ç÷
ç÷ ç÷ ç÷
ê ú ê úê ú
èø èø èø
ë û ë ûë û
The edge modification factor for anchor channel a is given
below.
0.5
1,
,,
1,
,
aa
Cr N ed N
aa
cr N
c
c C then
C
æö
£Y=
ç÷
èø
The edge modification factor for anchor channel b is given
below.
0.5
1,
,,
1,
,
ab
Cr N ed N
ab
cr N
c
c C then
C
æö
£Y=
ç÷
èø
Longitudinal shear
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.
Figure 9.2.13.10 — Longitudinal Shear — Plan view.