ETA 19/0665 v03 of 22/01/2020 page 18 of 18
Table C1: Essential characteristics for rebar under tension load in concrete
Rebar
ϕ
8
ϕ
10 ϕ 12 ϕ 14 ϕ 16
ϕ
20 ϕ 25 ϕ 26 ϕ 28 ϕ 30 ϕ 32
Diameter of rebar
ϕ
[mm]
8
10
12
14
16
20
25
26
28
30
32
Pull-out resistance
Characteristic bond resistance in uncracked concrete C20/25
Temperature range I:
40°C/24°C
Rk,ucr
[N/mm²]
12
Temperature range II:
80°C/50°C
Rk,ucr
[N/mm²]
10
Temperature range III:
120°C/72°C
Rk,ucr
[N/mm²]
8,5
Influence of cracked concrete
cr
[-]
0,53
0,58
0,61
0,64
0,73
Installation safety factor
Hammer drilling
inst
[-]
1,0
Hammer drilling with Hilti hollow
drill bit TE-CD or TE-YD
inst
[-]
1,0
Diamond coring with roughening
with Hilti roughening tool TE-YRT
inst
[-]
-
1,0
Bond-splitting resistance
Product basic factor
A
k
[-]
4,1
Exponent for influence of concrete
compressive strength
sp1
[-]
0,31
Exponent for influence of rebar
diameter
ϕ
sp2
[-]
0,32
Exponent for influence of concrete
cover c
d
sp3
[-]
0,67
Exponent for influence of
side
concrete cover (c
max
/ c
d
)
sp4
[-]
0,25
Exponent for influence of
anchorage length l
b
lb1
[-]
0,45
Influence factors
on bond resistance
Rk
Cracked and uncracked concrete:
Factor for concrete strength
c
C30/37
1,04
C40/45
1,07
C50/60
1,10
Cracked and uncracked concrete:
Sustained load factor
sus
40°C/24°C
0,74
80°C/50°C
0,89
120°C/72°C
0,72
Concrete cone failure
Factor for uncracked concrete
k
ucr,N
[-]
11,0
Factor for cracked concrete
k
cr,N
[-]
7,7
Edge distance
c
cr,N
[mm]
1,5
l
b
Spacing
s
cr,N
[mm]
3,0
l
b
Annex C1
of ETA N° 19/0665
Performances
Essential characteristics under tension load in concrete for bond-
splitting and concrete cone resistances