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
9.6.2 — HAC (T) EDGE, HAC (T)
EDGE LITE AND HAC S (T)
EDGE: DESIGN
In this section an overview of the verifications is given.
All the actions on the anchors are calculated according to
AC232. The action on the rebars are calculated with the model
of AC232 with a modification of the influence length. A summary
of the applied load distributions is given in Table 9.6.2.1.
In case of two elements close to an edge the actions on the
anchors are calculated independently for the two channels
resistances.
Following considerations are done for the verifications of the
three introduced components:
1) HAC-50 and HAC-T50 with reduced embedment depth: no
changes to the design is based on ESR3520 and AC232.
2) Lip strengthening element (Clip): in combination with the
clip higher values of V
sl,y
, V
sa,y
and V
sc,y
are provided. Seismic
design is performed according to the ESR3520: the lip
strengthening element is not considered in the seismic
calculation nor for load acting towards the slab (wind
pressure).
3) With the new Rebar Top of Slab front Plate (EDGE), the rebars
and the anchor channel are structurally uncoupled: the
connection between the two elements is weak and has no
structural function.
For tension loads, the rebars are neglected and all the
verifications are performed in the same way as for the standard
HAC channels, according ESR3520. The splitting failure
(considered in the concrete breakout verification) is not possible
when the EDGE front plate is combined (Ψ
cp,N
= 1.0) and the
concrete is always considered as cracked (Ψ
c,N
= 1.0).
For perpendicular shear a new method for concrete edge
failure and an additional reduction for the lip failure are
introduced. Additionally, the verification of rebar pull-out and
rebar steel strength are performed in the same way as for the
CRFOS U. Moreover, two remarks are added in Profis, the
first concerning the “concrete cone” for shear load and the
second concerning the presence of cracks at the sides of the
channel. Supplementary reinforcement for perpendicular or
for longitudinal shear is not permitted in combination with the
EDGE plate.
For longitudinal shear the rebars are neglected and the concrete
failure is calculated according to ESR3520. This assumption
is conservative since the capacity of unreinforced concrete is
lower than that of the edge with the EDGE reinforcement.
All the verifications under combined loads are performed
according to ESR3520.
If two anchor channels are placed close to a corner, all the steel
verification remain the same. Since the two channels use the
same concrete surface, some modification have to be done
for all the concrete verifications in order to take the relative
influence into account.
An adjustment to the ESR method for the calculation of concrete
cone and concrete edge failure in case of two (or more)
channels is described in Sections 9.2.7 to 9.2.17. For longitudinal
shear the reinforcement bars are neglected and the ESR method
is applied.
Conservative assumptions are done for the 3D load interaction.
Table 9.6.2.1 — Actions on the anchors.
Action HAC-(T)50 with EDGE front Plate HAC-(T)50 with EDGE front Plate + Clip
Anchor tension AC232 AC232
Anchor shear perpendicular AC232 AC232
Anchor shear parallel AC232 AC232
Rebar tension Mod. AC232 Mod. AC232
Tension (ΦN
n
) Shear (ΦV
n,y
) Shear (ΦV
n,x
)
Steel Concrete Steel Concrete Steel Concrete
Figure 9.6.2.1 — HAC (T) EDGE, HAC (T) EDGE Lite — HAC (T) EDGE ( C).
IMPORTANT! Failure analysis modes evaluated follow ACI 318-14,
chapter 17. This DOES NOT include evaluating the base material (e.g.
edge-of-slab) capacity to resist compressive forces generated by
the fixture. The engineer must ALWAYS verify the base material (e.g.
edge-of-slab) design is capable of resisting the applied loading.
For additional information, please contact Hilti at [e-mail]
Superposition of tension and shear loads
(up to 5 interaction equations)