1. Anchor
Channel Systems
2. HAC
Portfolio
3. HAC
Applications
12. Instructions
for Use
13. Field Fixes
14. Design
Example
ψ g,Nb = m
odification factor for effect of influence of the
bearing area of neighboring anchors
The modification factor to account for influence of the bearing
area of neighboring anchors, Ψ g,Nb , shall be computed in
accordance with Eq. (22) or Eq. (23).
ESR-3520 Equation (20)
If s < 4 c a 1 , then Y g , Nb =
n + ( 1 - n ).
s
³ 1 . 0
4 c a 1
ESR-3520 Equation (22)
odification factor for effect of distance to
ψ s,Nb = m
neighboring anchors
The modification factor accounting for the distance to and
loading of neighboring anchors, ψ s,Nb , shall be computed in
accordance with Eq. (10), however s cr,N shall be replaced by
s cr,Nb , which shall be computed in accordance with Eq. (21).
s cr , Nb = 4 c a 1 , in .( mm )
ESR-3520 Equation (21)
odification factor to account for influence of
ψ s,Nb = m
uncracked concrete
The following modification factor to account for influence of
uncracked concrete, ψ c,Nb , shall be permitted:
ψ c,Nb = 1.25
ESR-3520 Equation (23)
where:
n = number of tensioned anchors in a row parallel to the edge
ψ co,Nb = m
odification factor to account for influence of
corner effects
The modification factor to account for influence of corner
effects, ψ co,Nb , shall be computed in accordance with Eq. (24).
y co, Nb
æ c ö
= ç ç a2 ÷ ÷
è c cr, Nb ø
0.5
£ 1.0
ESR-3520 Equation (24)
ESR-3520 Equation (25)
Condition A (ϕ=0.75) is considered when
• Supplementary reinforcement is present
• Reinforcement does not need to be explicitly designed for the
anchor channel
• Arrangement should generally conform to anchor
reinforcement
• Development is not required
ϕ
A
B 0.75
0.70
Anchor cahnnel with deformed rebar anchors
Where anchors consist of deformed reinforcing bars, verification
for concrete breakout is not required provided that the deformed
reinforcing bars are lap spliced with reinforcing bars in the
member according to the requirements of ACI 318-14 Section
25.5. Refer Section 8.6 of Chapter 8 regarding splice length.
æ h + f
If f ³ 2 c a1 then y h, Nb = ç ç ef
è 4 c a1
ö æ 2 c a1 +
÷ ÷ £ ç ç
ø è 4 c a1
If f ³ 2 c a1 then y h, Nb = 1.0
f ö
÷ ÷
ø
ESR-3520 Equation (26)
ESR-3520 Equation (27)
Cast-In Anchor Channel Product Guide, Edition 1 • 02/2019
175
where:
f = distance between the anchor head and the surface of
the concrete member opposite to the anchor channel (as
illustrated in Figure 7.3.2.19), in. (mm)
174
The modification factor to account for influence of the member
thickness, ψ h,Nb shall be computed in accordance with Eq. (26)
or Eq. (27).
Condition
ψ h,Nb = m
odification factor to account for influence of the
member thickness
• No Supplementary reinforcement is present
If an anchor is influenced by two corners (c a2 < 2c a1 ), then
the factor, ψ co,Nb , shall be computed for c a2,1 and c a2,2 and the
product of the factors shall be inserted in Eq. (19).
Figure 7.3.2.18 — Blowout failure of a deep anchor near an edge. (Picture
from Anchorage in Concrete Construction, R. Eligehausen).
ϕ factor for concrete side-face blowout strength
Condition B (ϕ =0.70) is considered when
c a2 = c
orner distance of the anchor for which the resistance is
computed, in. (mm)
c cr, Nb = 2 c a1 , in . ( mm )
Figure 7.3.2.19 — Anchor channel at the edge of thin concrete member
N b
= basic concrete side-face blowout strength in tension
ψ s,Nb = modification factor for effect of distance to
neighboring anchors
ψ a,Nb = modification factor for effect of influence of the
bearing area of neighboring anchors
ψ co,Nb = modification factor to account for influence of corner
effects
ψ h,Nb = modification factor to account for influence of the
member thickness
ψ c,Nb = modification factor to account for influence of
uncracked concrete
N sb
= Basic concrete side-face blowout strength
11. Best
Practices
ESR-3520 Equation (19)
10. Design
Software
If s ³ 4 c a 1 , then Y g , Nb = 1 . 0
N sb 0 = 128 × l × c a1 × A brg . f c ' , lb
N sb 0 = 10 . 5 × l × c a1 × A brg . f c ' , N
9. Special Anchor
Channel Design
0
N sb = N sb
× ψ s, Nb × ψ g, Nb × ψ co, Nb × ψ h, Nb × ψ c, Nb , lb ( N )
The basic nominal strength of a single anchor without influence
of neighboring anchors, corner or member thickness effects in
cracked concrete, N 0sb , shall be computed in accordance with
Eq. (20).
8. Reinforcing
Bar Anchorage
f N sb ³ N
a
ua
N sb = Basic concrete side-face blowout strength
7. Anchor Channel
Design Code
For anchor channels with deep embedment close to an edge
(h ef > 2c a1 ) the nominal side-face blowout strength, N sb , of a
single anchor shall be computed in accordance with Eq. (19).
6. Loading
Tension-loaded headed studs provided
with small edge distances can generate
local blowout failures in the vicinity
of the head. Side blow-out failure will
govern the concrete capacity of studs
having small edge distance (concrete
cover) in combination with large
embedment depth. Local concrete side
blow-out failure is caused by the quasi-
hydrostatic pressure in the region of
the head of the stud which gives rise
to a lateral bursting force. The failure
load will increase in proportion to the edge distance c a1 . For
anchor channels located perpendicular to the edge and loaded
uniformly, verification is only required for the anchor closest to
the edge.
5. Base material
Concrete side-face blowout strength фN sb
4. Design
Introduction