1. Anchor
Channel Systems
2. HAC
Portfolio
3. HAC
Applications
4. Design
Introduction
5. Base material
6. Loading
Introduction
Prior to the publication of the Acceptance Criteria 232 (AC232),
cast-in anchor channels could not receive recognition under
the International Building Code (IBC) as ACI 318 Anchor-to-
Concrete provisions exclude specialty inserts. The publication
of (AC232) brought major benefits to the cast-in anchor channel
industry and design community. The use of optimized anchor
channel solutions and simplification of the design and approval
processes for anchor channels ultimately can avoid construction
shutdowns.
Important design provisions have been added to AC232
over the last years. The ultimate goal is to have a complete
framework that covers all common applications encountered
in a building such as corners with a pair of anchor channels
loaded simultaneously, parallel channels, and wind corner zones
with practical design requirements (i.e typical edge distance).
For these conditions, it is typically concrete that is limiting
factor and having “fixed” design parameter such as member
thickness, concrete type, concrete compressive strength, etc.,
brings the need of the so call anchor channels with rebars.
9. Special Anchor
Channel Design
10. Design
Software
11. Best
Practices
12. Instructions
for Use
13. Field Fixes
14. Design
Example
Table 9.1.1 — Overview of Hilti anchor channel systems design method
Tension design model
Symbol HAC
HAC-T HAC CRFoS U
HAC-T CRFoS U HAC EDGE
HAC-T EDGE
Anchor ΦN sa ESR-3520 AC232 based 1 ESR-3520
Anchor and channel connection ΦN sc ESR-3520 AC232 based 1 ESR-3520
Channel lip ΦN sl ESR-3520 AC232 based 1 ESR-3520
ΦM s,flex ESR-3520 ESR-3520 ESR-3520
Channel bolt ΦN ss ESR-3520 ESR-3520 ESR-3520
Pullout ΦN pn ESR-3520 ACI 3182 ESR-3520
Side-face blowout ΦN sb ESR-3520 N/A ESR-3520
Concrete breakout ΦN cb ESR-3520 N/A ESR-3520
Failure mode
Bending of channel
Perpendicular shear design model
HAC
HAC-T HAC CRFoS U
HAC-T CRFoS U HAC EDGE
HAC-T EDGE
Channel lip ΦV sl,y ESR-3520 AC232 based 1 ESR-3520
Anchor ΦV sa,y ESR-3520 AC232 based 1 ESR-3520
Anchor and channel connection ΦV sc,y ESR-3520 AC232 based 1 ESR-3520
Channel bolt ΦV ss ESR-3520 ESR-3520 ESR-3520
Channel bolt with bending ΦV ss,M ESR-3520 ESR-3520 ESR-3520
Concrete edge breakout ΦV cb,y ESR-3520 ESR-3520 Hilti Method 3
Pryout ΦV cp,y ESR-3520 N/A ESR-3520
Symbol
Failure mode
Cast-in anchor channels can now receive recognition under the
IBC, as AC232 3.0 Design Requirements provides amendments
to ACI 318 Anchoring-to-Concrete provisions that permit the
design of anchor channel systems as if they were included in
ACI 318 Anchoring-to-Concrete provisions. In addition, AC232
allows the design community to have a clear understanding of
the behavior of cast-in anchor channel systems.
In 2015, AC232 incorporated the so needed seismic provisions
for anchor channels in Seismic Design Category C, D, E, or F.
Later that year, provisions permitting the use of anchor channels
in all-lightweight concrete and sand-lightweight concrete were
adopted by AC232.
8. Reinforcing
Bar Anchorage
9.1 — O
VERVIEW OF HILTI ANCHOR CHANNEL
SYSTEMS DESIGN
7. Anchor Channel
Design Code
Longitudinal shear design model
Figure 9.1.1 — Anchor Channel Code Landscape
Since its inception, AC232 has been an ever-evolving
document. In its infancy stage, it did not include provisions
for the qualification and design of anchor channels systems in
structures assigned to Seismic Design Category C, D, E, or F.
216
HAC CRFoS U
HAC-T CRFoS U HAC EDGE
HAC-T EDGE
The scope of AC232 is limited to anchor channels with rounded
headed anchors or I-anchors and anchor channels with rebars
replacing headed anchors or I-anchors. AC232 includes
provisions for anchor reinforcement, where the concrete
breakout in shear and/or tension can be precluded, but
specifying additional reinforcement implies additional burdens
and is typically an unpractical solution. The use of a complete
anchor channel systems that allow the introduction of higher
loads into the structure without specifying anchor reinforcement
is the preferred solution.
Anchor ΦV sa,x ESR-3520 AC232 based 1 ESR-3520
Anchor and channel connection ΦV sc,x ESR-3520 1 AC232 based ESR-3520
Channel bolt and channel connection ΦV sl,x ESR-3520 AC232 based 1 ESR-3520
Channel bolt ΦV ss ESR-3520 ESR-3520 ESR-3520
Channel bolt with bending ΦV ss,M ESR-3520 ESR-3520 ESR-3520
Concrete edge breakout ΦV cb,x ESR-3520 ESR-3520 ESR-3520
Pryout ΦV cp,x ESR-3520 N/A ESR-3520
All Hilti anchor channels covered by AC232 (HAC and HAC-T) are
designed in accordance to ESR-3520. Hilti’s mission is to create
a better future. That is why these so needed anchor channels
with rebars are tested in accordance with AC232 and the design
models are using AC232 principles and applicable provisions
of AC232 and ACI 318. Table 9.1.1 provides a summary of the
design method of the Hilti anchor channel systems. Our ultimate
goal is to offer designers and contractors anchor channel
system solutions that are 100 percent IBC compliant.
1 A
C232 based indicates product has been tested in accordance to AC232 testing protocols for that specific failure mode and the design is based on applicable provisions and/or fundamentals
of AC232 and/or ACI 318.
2 ACI 318 indicates the analysis of that specific failure modes is in accordance to the applicable ACI 318 provision.
3 Hilti method is derived based on testing according to AC232 testing protocols for that specific failure mode. However, the design is adjusted accordingly to account for the additional
contribution of the added rebars.
Cast-In Anchor Channel Product Guide, Edition 1 • 02/2019
217
Relying on technical data is adequate only if the tests are
performed correctly. Tests results can be positively or negatively
altered if they are not tested properly. Technical data via testing
was a problem since prior to AC232, there were no testing
protocols for cast-in anchor channel systems. As mentioned
in chapter 7, AC232 provides testing protocols and design
guidelines for anchor channels.
HAC
HAC-T
Failure mode
Prior to AC232, designers had to design via engineering
judgment, applying provisions not fully applicable to anchor
channels, research papers, and/or using manufactures’
technical data. The design methodology used to approve the
anchor channel design would have to be backed-up by the
P.E. stamp of a licensed engineer of the state of the project’s
location and still might have to go to local jurisdiction for final
approval. In some extreme cases, this was not accepted by
local jurisdictions and additional testing was required. This
added an extra problem since testing protocol for anchor
channels did not exist neither.
Symbol
Figure 9.1.2 — HAC Channel Protfolio