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
Acute corners
Perpendicular Shear: Corner distance shall be considered as
the shortest distance between the intersection of the formation
of failure planes using C
cr,V
as shown in the Figure 9.2.4.5. The
straight line is drawn (representing path of least resistance)
extending out straight until it intersects the inclined slab edge.
Which is then extended back on to the perpendicular edge. The
C
a2
is measured from that point onwards to the closest anchor.
Tension: Corner distance shall be considered as the shortest
distance between the intersection of the formation of failure
cones C
cr,N
as shown in the Figure 9.2.4.6. The circle with radius
of C
cr,n
and the shortest intersection of that circle with the edge
is C
a2
distance.
Longitudinal Shear: Corner distance shall be considered as
the shortest distance between the intersection of the formation
of failure cones using 1.5 C
a1
as shown in the Figure 9.2.4.7.
The C
a1
distance is assumed, where the 35° line intersects the
inclined portion of the slab.
Figure 9.2.7.5 — Acute angle ToS corner with anchor channels on one sides
— Perpendicular shear.
Figure 9.2.7.6 — Acute angle ToS corner with
anchor channels on one sides — Tension.
Figure 9.2.7.7 — Acute angle ToS corner with anchor channels on one sides
— Longitudinal shear.
9.2.8 — HAC AND HAC-T DESIGN: TOP OR BOTTOM OF SLAB WITH
PAIR OF ANCHOR CHANNEL ADJACENT TO EACH OTHER
Minimum distance that does not reduce the concrete
capacity in tension and perpendicular shear: The capacity
of anchor channel should be reduced because of the presence
of the adjacent anchor channel. The anchor channels installed
next to each other and subjected to perpendicular shear and
tension as seen in Figure 9.2.8.1 does not require the reduction.
The reason for this is that the breakout failure plane in shear
and breakout failure cones in tension has been completely
developed on the left side of channel a and right side of
channel b. There is no overlapping of the breakout cones
from the adjacent anchor channel. The shear breakout planes
as represented by the red shaded area and breakout failure
cone in tension as represented by brown circle are completely
developed.
In order to make sure that there is no influence of the adjacent
anchor channel on the concrete capacity, it is recommended to
have them installed at least at a distance 2*Max(C
cr,v
; C
cr,N
).
Please refer to anchor channel theory for detailed instruction on
the factor C
cr,v
and C
cr,N
. Below are the equation defining these
variables.
efef
ef
Ncr
hh
h
s 3
1.7
3.1
8.22
,
³
÷
÷
ø
ö
ç
ç
è
æ
-=
efNcrNcr
hsc 5.15.0
,,
³=
).(b2cs0.5c
cha1Vcr,Vcr,
mmin+=×=
Figure 9.2.8.1 — TOS and BOS with pair of anchor channel adjacent to each other — Tension and perpendicular capacity doesnot get reduced.
Figure 9.2.8.2 — TOS and BOS with pair of anchor channel adjacent to each other — Overlapping tension and perpendicular shear concrete cones.