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
Longitudinal shear analysis:
The reduced side edge distance needed to be conservatively
considered as shown in Figure 9.2.3.14 as done for
perpendicular shear for determining the longitudinal shear
capacity.
Interaction Equation:
Interacting the concrete utilization in tension, perpendicular
shear and longitudinal shear of both channel will include the
effect of all of these breakout cones as described below. Refer
section for 90° corner describing the longitudinal shear check.
3D Load Interaction for Front of Slab solutions (verification for
every anchor):
with α=1.67
!
"#
#
$%!
&'
:
Tension of anchor channel in consideration (channel b)
• Concrete breakout in tension utilization (anchor, including
influence of the other channels)
• Pull Out Strength Utilization
: Longitudinal shear of anchor
channel on acute edge (channel a)
• Longitudinal concrete edge failure utilization
• Anchor reinforcement for concrete edge failure
!
"#,%
#
&'!
(),%
:
: Perpendicular shear of anchor channel in
consideration (channel b)
• Maximum Concrete edge breakout utilization for
Perpendicular shear
!
"#,%
#
&'!
(),%
:
: Longitudinal shear of anchor channel in consideration
(channel a)
• Concrete edge (anchor)
• Anchor reinforcement for concrete edge failure
Please note that using this interaction equation is a conservative
method to incorporate longitudinal force utilization in the
analysis. In order to optimize the design contact Hilti. We
will optimize the design using the method that takes into
consideration the longitudinal utilization of both the anchor
channels.
Figure 9.2.3.13 — Acute FoS corner with anchor channels on both sides —
Example of determination of ψ
s,v,a1
.
Figure 9.2.3.14— Acute FoS corner with anchor channels on both sides —
Effect of longitudinal, perpendicular shear and tension.
Obtuse Corner
Tension:
Obtuse angle corners with headed studs HAC channel loaded
only in tension: The crack will propagate along the path of least
resistance at the corner instead of following idealized failure
plane. The side edge distance used in the analysis should be
as shown in Figure 9.2.3.15. This approach is followed in order
to avoid utilizing the same concrete twice in the analysis, hence
generating the results replicating the real condition. The shaded
region of concrete shown in Figure 9.2.3.15 is not utilized.
The shaded area for obtuse angle corner with headed studs
anchor channel the true side edge can be used once in an
analysis as shown in Figure 9.2.3.16. Assigning true edge to
one channel and assigning reduced edge to another channel.
Concrete breakout in tension check for Channel a, the reduced
side edge is C
a2,a
can be used in the analysis. Concrete breakout
tension check for Channel b, the true side edge is C
a2,b
can be
used in the analysis. The total distance of (a+b) can be divided
between the two channels, while analyzing the individual
channels. For example if channel a is loaded more than channel
b than side edge distance of 3/4(a +b) can be assumed for
channel a and side edge distance 1/4(a+b) can be assumed for
channel b.
Perpendicular shear:
Concrete breakout perpendicular shear check at outside
corner for Channel a or b, the side edge distance of true edge
is considered for analysis in determining the perpendicular
shear capacity. True side edge distance is the distance from
the anchor to the corner edge at the corner. Moreover, the ψ
s,v
is calculated taking into consideration the respective distances
of neighboring anchors with respect to the anchor that is in
consideration. Refer to 90° corner section describing the
method in detail. Please refer to the Figure 9.2.3.17.
ψ
s,V
modification factor for spacing influence for acute angle
corner:
Example of spacing factor ψ
s,v
calculation for a
1
of channel a
with respect to a
1
channel b on the other side of obtuse angle
corner. Please refer to the Figure 9.2.3.17.
=
'()
; ℎ
'()
,
= ∗
= ∗ .
s
"#,%
= 2 ∗
2
= 2 ∗ 1.13
s,v,a1
1.5 1.5 1.5 1.5
b,1,1 , 1 b,1,2 , 2 b,1,3 , 3 a,1,2 , 2
cr,v , 1 cr,v , 1 cr,v , 1 cr,v , 1
1
ss ss
11 1 1 1
ssss
aa aa
ua b ua b ua b ua a
aaaa
ua a ua a ua a ua a
VVVV
VVVV
y
=
é ùé ùé ùé ù
æö æö æö æö
ê úê úê úê
+ -×+ -×+ -×+ -×
ç÷ ç÷ ç÷ ç÷
ç÷ ç÷ ç÷ ç÷
ê úê úê úê
èø èø èø èø
ë ûë ûë ûë û
1.5
a,1,3 , 3
cr,v , 1
s
1
s
a
ua a
a
ua a
V
V
éù
æö
úê ú
+ -×
ç÷
ç÷
úê ú
èø
ëû
ψ
co,V
modification factor for corner influence for an obtuse angle
corner: A true side edge distance is taken into consideration
for determination of reduction factor for corner distance C
a2,a
or
C
a2,b
is taken as distance in case of a obtuse angle corner for
corner anchor a
1
and b
1
respectively.
2, , ,
0.5
2,
2, , ,
,
1.0
1.0
a a cr v co V
aa
a a cr v co V
cr V
If C C than
C
If C C than
C
y
y
³ =
æö
<=£
ç÷
ç÷
èø
,1
,, 1
24
0.5 2
cr v ch a
cr v cr v ch a
S bC
C S bC
=+
= =+
C
a2
=(C
a2,a
) distance of the anchor a
1
under consideration to the
corner (see Figure 9.2.3.17).
Figure 9.2.3.15 — Obtuse angle FoS corner with anchor channels on both
sides — Tension analysis.
Figure 9.2.3.16 — Obtuse angle FoS corner with anchor channels on both
sides — example of Tension analysis.