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
11.1 Code Compliance 11.2 HAC Price Index 11.3 Design Optimization 11.4 HAC Layout 11.5 Substrate Considerations 11.6 HAC Specications
Example
As-is
Design status: Not ok
Anchor channel: HAC-50 106/300 F
Utilization: 107%
Bolt spacing: 5.00”
Anchor channel Price Index: 0.24
Solution option 1: use HAC CRFoS U
Design status ok
Anchor channel: HAC-50 356/300 F CRFoS U
UUtilization: 64%
Bolt spacing: 5”
Anchor channel Price index: 0.51
Solution option 2: use longer HAC with increased bolt
spacing
Design status: ok
Anchor channel: HAC-50 106/450 F
Utilization: 100%
Bolt spacing: 7.125”
Anchor channel Price Index: 0.335
Conclusion:
Solution option 2 provides a price
differential index of 0.175 (0.51-0.335).
This is roughly 73% on HAC savings
by just increasing the t-bolt spacing by
2.125"!
Steel:
Anchor ΦN
sa
Connection anchor-channel, ΦN
sc
WORK-AROUND: ADD ANCHORS
If concrete strength does not control but the anchor-channel
connection and anchor strength is limiting the design, consider
using an anchor channel with more anchors. Refer to price
index to asses if an anchor channel with more anchors or a
bigger channel is more economical.
Note: adding more anchors may negatively impact the concrete
breakout strength of the anchor under consideration. For
HAC CRFoS U, there is no concrete breakout in tension and
therefore, adding more anchors is always a viable solution.
Bending of channel, ΦM
s,flex
WORK-AROUND: INCREASE T-BOLT SPACING
OR REDUCE ANCHOR SPACING
Flexure of the anchor channel is another failure mode where
the resistance is derived via testing and cannot be increased.
However, the applied flexural forces can be reduced by
increasing the t-bolt spacing or reducing the anchor spacing.
The applied bending moment at the channel is derived under the
simplified model where the channel profile is treated as a simple
supported beam, with a span equal to the anchor spacing.
See price index to determine if it is more feasible to use a bigger
anchor channel or to add an anchor.
Channel lip, ΦN
sl
WORK-AROUND: ADD A T-BOLT, ADD AN
ANCHOR OR INCREASE T-BOLT SPACING
The channel lip strength is a value derived via testing. The
design strength of the channel lip may be reduced if the t-bolt
spacing spaced closely is less than 2 times the width of the
channel profile, (2b
ch
) and are loaded simultaneously (in tension).
One of the 5 interaction equations requires the verification of the
channel lip in tension combined with the flexural strength of the
channel profile. The applied bending moments can be reduced
by reducing the anchor spacing.
The work around for applications where the channel lip strength
is not adequate is adding a t-bolt or increasing the t-bolt
spacing. This is generally acceptable at corner conditions. For
typical conditions, adding a t-bolt may have the same cost as
going to a bigger channel size. For other applications, the use of
a bigger channel profile may be required.