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
ℓ
d
= development length, in.
ℓ
d
≥ 12 in.
f
y
= yield strength of bar
Rebar cover factor is:
a) the least of the side cover
b) the concrete cover to the bar or wire
c) One-half the center-to-center spacing of the bars.
In all cases, c
b
is measured from the center of the bar.
c
b
minimum of:
a) c
b1
b) c
b2/2
c) c
b3
d) c
b4
Figure 9.3.4 — Rebar Cover — HAC CRFOS U — Section View
Figure 9.3.5 — Rebar Cover — HAC CRFOS U — Plan View
Hilti offers a special anchor channel with rebars for front of
slab applications. The rebar which is connected to the channel
profile is kinked in order to also allow the installation of two
anchor channels in a corner (see Figure 9.3.5). This product is
called CRFoS U (U = universal installation close to an edge or in
a corner).
Figure 9.3.5 — HAC CRFOS U. Figure 9.3.6-b — Tension
test setup universal testing
machine.
Tests have been performed on CRFoS (U) to demonstrate that,
in front of slab applications no hairline cracks or spalling in the
most critical condition ( corner condition and minimum slab
thickness) are observed due to the kinked rebar before steel
failure of the anchor channel occurs.
The steel strength of the channel lips (N
sl
), connection between
anchor/rebar and channel profile (N
sc
) and anchor (N
sa
) is derived
from a tension test in a universal testing machine without being
cast into concrete (test series 1 in AC232). In this test series
one anchor is fixed to the testing frame (see Figure 9.3.6-b).
A channel bolt is inserted directly over the anchor and loaded
without a fixture.
The test setup is shown in Figure 9.3.7.
Figure 9.3.7 — Tension test setup for testing anchor channels under static
and simulated seismic conditions.
Evaluation of test results:
The test results shows that no hairline cracks were observed
under static and simulated seismic conditions prior to failing the
connection between rebar and channel profile.
The one diameter kink is provided in CRFoS U anchor channel.
Hence in the PROFIS report there will be a k value of a diameter
representing the kink in the rebar.
Perpendicular Shear
Steel Failure Modes Concrete Failure Modes
Channel bolt:
ΦV
ss
Channel Lip
ΦV
sl,y
connection :
ΦV
sc,R,y
Rebar
ΦV
s,R,y
Concrete
Breakout
Φ
Vcb,y
Concrete Pryout
ESR-3520
Sec. 4.1.3.3.2,
4.1.3.4.2
Refer to anchor
channel theory
ESR-3520
Sec. 4.1.3.3.2,
4.1.3.4.2
Refer to anchor
channel theory
Hilti Method
based on
AC232 testing
protocols
Hilti Method
based on AC232
testing guidelines
ESR-3520
Sec. 4.1.3.3.3
Refer anchor
channel theory
N/A
Rebar strength: ΦV
s,R,y
ΦV
s,R,y
> V
a
ua
The tests follow AC232 testing
guidelines. Refer to anchor channel
theory for further clarification. Please
refer to table 2.3.4.1 for strength
values.
Rebar: ΦV
s,R,y
Connection Anchor and Channel : ΦV
s,R,y
ΦV
s,R,y
> V
a
ua
The tests follow AC232 testing
guidelines. Refer to anchor channel
theory for further clarification. Please
refer to table 2.3.4.1 for strength
values.
Rebar and channel
connection: ΦV
s,R,y
Concrete breakout in perpendicular shear: ΦV
cb,y
ΦV
cb,y
> V
a
ua
Please refer to anchor channel theory
for more information on this failure
mode. The design methodology is the
same as that of headed stud anchor
channel. This check is compliant with
ESR 3520.
Concrete edge breakout:
ΦV
cb,y