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
9.2.1 — HAC AND HAC-T DESIGN: INTERMEDIATE APPLICATIONS
HAC and HAC-T at intermediate
applications are designed in accordance
with ESR-3520. Design methodology
is fully in accordance with the anchor
channel Design Code presented in
chapter 7.
Figure 9.2.1.1: FOS Figure 9.2.1.2:TOS
9.2.2 — HAC AND HAC-T DESIGN: FACE OF SLAB OUTSIDE CORNER
WITH A SINGLE ANCHOR CHANNEL
90° corners
Outside corners where only one anchor channel is present are fully covered by ESR-
3520. The design methodology is fully in accordance with the anchor channel Design Code
presented in Chapter 7.
AC232 includes design provisions to account for the influence of a corner. The concrete
strengths in tension and shear of the anchor channel may be reduced (depending on how
far the anchor channel is away from the corner) since the concrete cones may not be fully
developed. See chapter 7 for design provisions for corners.
In PROFIS Anchor Channel, these conditions can be simply modeled by reducing the corner
distance.
Acute and obtuse corners
Although AC232 does not specifically
address acute and obtuse corners, Hilti's
general recommendation is to not follow
the idealized failure planes but the path
of least resistance to assess the concrete
volume available for the anchor channel.
Upon determination of the corner
distance, AC232 provisions can be used
to analyze this type of corners.
In order to avoid calculating
unconservative concrete strength, the
path of least resistance for the crack
should be always considered.
Obtuse corners: Tension
analysis
Corner distance shall be considered
assuming an imaginary edge at the joint
of the corner. The following two options
that has been illustrated and used for the
analysis
OPTION I. This condition should be
modeled in PROFIS anchor channel
software with a corner (C
a2
) distance
of the closest anchor and the corner.
Therefore, the concrete represented by
the darker shade of gray shall be ignored.
OPTION II: This is an optimized condition
where the analysis of the a
1
anchor is
performed using new h
’
eff
as the new
embedment depth with side edge
distance of C
’
a2
and ignoring the concrete
represented by the darker shade of gray.
The h
eff
for rest of the other anchors will
not change. This can be solved using
hand calculations only. Please contact
Hilti for support if any obtuse angle
conditions need an optimized solution.
Figure 9.2.2.2 — Obtuse — Tension-Option I. Figure 9.2.2.3 — Obtuse -Tension-Option II.
Figure 9.2.2.1: 90° Corner with single
channel.
Obtuse corners: Perpendicular shear analysis
Conservatively the side edge distance of C
a2
should be assumed
as seen in figure: 9.2.2.4 and figure: 9.2.2.5 because of the
discontinuity in the propagation of breakout failure plane in
perpendicular shear. This will reduce the perpendicular shear
capacity by introducing the reduction factor for corner effect.
).(b2cs0.5c
cha1Vcr,Vcr,
mmin+=×=
ESR-3520 Equation (36)
0.5
a2
co,V
cr,V
c
1.0
c
y
æö
= £
ç÷
ç÷
èø
ESR-3520 Equation (35)
Figure 9.2.2.4 — Obtuse corner — perpendicular shear —Section view.
Figure 9.2.2.5 — Obtuse corner — perpendicular shear —Plan view.
Obtuse corners: Longitudinal shear analysis
Conservatively the side edge distance of C
’
a1
should be
assumed as seen in figure: 9.2.2.6 and figure: 9.2.2.7 because
of the discontinuity in the propagation of breakout failure plane
in longitudinal shear. Having a C
’
a1
will reduce the A
vc
and also
reduces V
b
, (V
b
basic longitudinal shear capacity depends on
the longitudinal distance) which in turn reduces the Longitudinal
shear capacity as seen in fig 9.2.2.6.
bV parallel,V h,V c,V ed, vco vcxcb,
.Vψ ψ ψ ψ)A/A(V ××××=
ESR-3520 Equation (44)
Figure 9.2.2.6 — Obtuse corner — Longitudinal shear —Section view.
Figure 9.2.2.7 — Obtuse corner — Longitudinal shear —Plan view.