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
9.2.13 — HAC AND HAC-T DESIGN: PARALLEL CHANNELS
Two TOS or BOS channels:
Currently, AC232 excludes parallel anchor channels. Hilti anchor
channel analysis of parallel anchor channels are based on ACI
318 provisions. The analysis of the concrete breakout strength
in shear is based on ACI 318 principles in conjunction with
AC232 design methodology.
All steel failure modes are in accordance to ESR-3520.
Concrete breakout strength in shear of parallel anchor channels
is per ACI 318 concepts pertaining to dividing the concrete
between the two channels.
Perpendicular Shear
Case 1: One assumption of the distribution of forces indicates
that half of the shear force would be critical on the front anchor
and the projected area. For the calculation of concrete breakout,
c
a1
is taken as c
a1,a
.
Figure 9.2.13.1— ACI-Fig. R17.5.2.1b—Calculation of A
vc
for single anchors
and groups of anchors per ACI 318-14..
Front anchor channel analysis: Refer Figure 9.2.13.2 and
9.2.13.3. The perpendicular concrete breakout strength of front
channel should be evaluated using the concrete edge distance
of c
a1,a
. The front anchor channel should be loaded with half
of the total shear force acting on the double anchor channel
system. This is required to be checked following ACI 318-14
chapter 17 section commentary Fig17.5.2.1b case I. This is
shown in Figure 9.2.13.1.
Figure 9.2.13.2 — Parallel Channels-Perpendicular Shear CaseI-Plan.
FFigure 9.2.13.3 — Parallel Channels — Shear CaseI-Section view.
Case 2: Another assumption of the distribution of forces
indicates that the total shear force would be critical on the
rear anchor and its projected area. This assumption needs to
be considered only when anchors are welded to a common
plate independent of "s". In the case of anchor channels, this
condition is applicable for "filled" holes conditions.
This provision is checked for parallel double channels in order
to confirm that the total available concrete between the back
channel of the parallel channels and the front edge has sufficient
capacity to take the total shear force experiencing by the
system.
Figure 9.2.13.4 — Fig. R17.5.2.1b — Calculation of A
vc
for single anchors
and groups of anchors per ACI 318-14..
Back anchor channel analysis: Refer Figure 9.2.13.5 and
9.2.13.6. The perpendicular concrete breakout strength of the
back channel should be evaluated using the concrete edge
distance of c
a1,b
. The back anchor channel should be loaded
with the total shear force acting on the double anchor channel
system. This is required to be checked following ACI 318-14
chapter 17 section commentary Fig17.5.2.1b case II. This is
shown in Figure 9.2.13.4.
Both Case 1 and Case 2 should be evaluated to determine which
controls for design.
Figure 9.2.13.5 — Parallel Channels-Shear CaseII-Plan view.
Figure 9.2.13.6 — Parallel Channels-Shear Case II-Section view.