HAC_Technical-Guide

394 395
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
Code Discussion Calculations
Step 4: Steel strength Anchor and connection between anchor and channel profile.
ESR-3520 section
4.1.3.6
Combined tension and shear loads (Interaction)
Anchor and connection between anchor and channel (Anchor a3) The interaction
check for steel failure of the channel requires the ratio (factored load acting on the
anchor element/anchor element or anchor-channel connection design strength) to be
checked using Equation (44) in ESR-3520. V
a
ua,x
=0lbs
2
,,
,,
,, ,,
max , max , max , 1.0
aa
aa
aa
ua y ua y
ua x ua x
ua ua
sa sc sa y sc y sa x sc x
VV
VV
NN
NN V V V V
a
a
ff f f f f
æö
æö
æö
++£
ç÷
ç÷
ç÷
ç÷
ç÷
èø
èø
èø
Governing failure mode in tension is Connection anchor-channel.
N
a
ua
β
N,sc
= _______
Ф N
sc
Governing failure mode in shear is Anchor/connection - perpendicular shear.
V
a
ua ,y
β
V,s a ,y
= _______
Ф V
sa,y

2
N,ac
=0.01770

2
V,sa,y
= 0.07528
= 1.00000
0.01770 + 0.07528 ≤ 1.00000
Utilization : 10%.
Code Discussion Calculations
Step 5: Steel strength local flexure channel lip and flexure of channel
ESR-3520
section 4.1.3.2.2
Channel lip strength in tension: ESR-3520 Section 4.1.3.2.2 requires a check to made
to determine if the clear distance between two T-bolts (s
chb
) is > the parameter 2(b
ch
),
where bch corresponds to the channel width. Values for bch are given in Table 8-1 of
ESR- 3520.
If schb is < 2(b
ch
), the value for N
sl
given in ESR-3520 Table 8-3 must be reduced by
the parameter calculated using Equation (5) in ESR- 3520. Calculate nominal tension
strengths (N
n
) nominal strength corresponding to local failure of channel lips Ф N
sl
,
Reference ESR-3520 Table 8-1 and Table 8-3.
Check:
s
chb
> 2b
ch
Reference ESR-3520 Section 4.1.3.2.2.
s
chb
= clear distance between T-bolts Reference ESR-3520 Figure 8-5.
b
ch
= channel width Reference ESR-3520 Table 8-1.
If s
chb
is < 2b
ch
, calculate the reduction factor
and multiply N
sl
, by this factor.
N
sl
, for an HAC-50F channel = 7865 lb Ф=0.75
Reference ESR-3520 Table 8-3. Ф N
sl
≥ N
s
ua
T-bolts are spaced at 6
in o.c.
Each bolt has a diameter
= 16 mm.
s
chb
= 6 in – (16 mm)(1
in/25.4 mm) = 5.37 in
HAC-50F channel width
(b
ch
) = 1.65 in → 2(b
ch
) =
3.3 in
5.37 in > 3.3 in → no
reduction required.
,
850
5899
: x100 15%
b
ua
sl
b
ua
N sa
sl
N lbs
N lbs
N
N
f
b
f
=
=
=
ESR-3520
section 4.1.3.3.2,
4.1.3.4.2
Strength for local flexure of channel lip — perpendicular shear load w/o lever arm
Ф V
sly
≥ V
a
uay
Nominal strength corresponding of channel lip → V
sly
Reference ESR-3520 Table 8-5.
α = 2 for anchor channels with V
sl,y
≤ N
s,l
α = 1 for anchor channels with V
sl,y
> N
s,l
It shall be permitted to assume reduced values for Vsl,y corresponding to the use
of an exponent α = 2. In this case the reduced value for Vsl,y shall also be used in
Section 4.1.3.3.1a).
V
sly
for the anchor element of an HAC-50F channel
V
sl,y
= 7868 lb for α = 2 V
sl,y
= 10,675 lb for α = 1
Ф = 0.75
,
,
,
,,
,
,
,,
1750
2
5899
: x100 30%
1
8006
: x100 22%
b
ua y
sl y
b
ua y
V sl y
sl
sl y
b
ua y
V sl y
sl
V lbs
When
V lbs
V
V
When
V lbs
V
V
a
f
b
f
a
f
b
f
=
=
=
=
=
=
=
ESR-3520
section 4.1.3.2.2
Flexure of channel in tension:
Ф M
s,flex
≥ M
u,flex
nominal strength corresponding to channel bending: ФM
s,flex
Reference ESR-3520 Table 8-3.
M
s,flex
for an HAC-50F channel with an HBC-C T-bolt = 14,125 in-lb Ф=0.85
Note that the value for M
s,flex
corresponds to the type of T-bolt being used.
HBC-C bolts are being used for this example.
,
,
,
,
,
83.6
12006
: x100 1%
u flex
s flex
u flex
N sa
s flex
M in lbs
M lbs
M
M
f
b
f
= -
=
=