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Göteborg, Sweden, September 13, 2017
Cracking and durability in FRC
G. Plizzari
University of Brescia, Italy
2/60 Göteborg, Sweden, September 13, 2017
Outlines
Cracks in Reinforced Concrete elements
Experimental program
Crack formation and development
Crack width and crack spacing
Concluding remarks
3/60 Göteborg, Sweden, September 13, 2017
Cracks in RC elements
4/60 Göteborg, Sweden, September 13, 2017
FRC to enhance crack control in RC elements
Short fibers having a straight or deformed shape
uniformly dispersed in the concrete matrix.
Fibers activate after cracking by bridging the crack.
The concrete is able to transmit higher forces
between the crack planes.
(1) Fiber reinforcement increase the concrete post-cracking tensile residual strength
(transmitted at crack location)
(2) Fiber reinforcement increase the bond between concrete and rebars
5/60 Göteborg, Sweden, September 13, 2017
Comparison of the behaviour of RC and RC+FRC tensile members:
srRC
se
c=fctm
bm
D-Region
steel stress
concrete stress
bond stress
c=0
ltRC lt
RC
NN
crack disturbed zone
bm
D-Region
ltRC+FRC lt
RC+FRC
NN
crack disturbed zone
srRC+FRC
se
c=fctmc=fctm
(1) FRC local tension softening
behaviour (simplified law):
fctm
fctm
At crack locations: FRC exhibits a
noticeable toughness with respect
to plain concrete
By adding fibers (1)+ (2): - reduction of crack spacing: reduction of srm
- reduction of average member strain at a given applied force: increase of
tension stiffening
(2) Increase of steel-to-concrete bond due to fiber reinforcement
Research significance
6/60 Göteborg, Sweden, September 13, 2017
0
2
4
6
8
10
12
14
0 0.1 0.2 0.3 0.4 0.5 0.6
Loaded End Slip [mm]
Bo
nd
Str
es
s [
MP
a]
Normal strength concrete
High strength concrete
Nor. str. fiber reinf. concrete
High str. fiber reif. concrete
No stirrups
=0
B=4
Bond in FRC elements
7/60 Göteborg, Sweden, September 13, 2017
Bond in FRC elements
8/60 Göteborg, Sweden, September 13, 2017
Experimental program
Flexural behaviour of a RC
beam having constant or
low gradient bending
moment
Beam cross-section:
effective area
surrounding
longitudinal steel
reinforcing bars
Prismatic SFRC samples with a central rebar: SFRC tension tie
9/60 Göteborg, Sweden, September 13, 2017
Experimental program
A broad experimental study was carried out.
The following key-parameters were investigated:
- Concrete cylinder compressive strength: from 27 MPa to 47 MPa
- Square element size: from 50 to 200 mm
- Clear concrete cover: from 20 to 85 mm
- Effective reinforcing ratio: from 0.98 to 3.26%
- /eff ratio: from 306 mm to 2043 mm
- Bar diameter: from 10, 20 and 30 mm
- Specimen length: from 950 mm to 1500 mm
- Volume fraction of fibres: from 0 to 1%
- Type of fibres
More than one hundred prismatic tensile ties were tested
10/60 Göteborg, Sweden, September 13, 2017
Vf b
[mm]
As
[mm2]
Ac,eff
[mm2]
Reinf.
Ratio (%)
Clean
cover
[mm]
Denomination # of
specimens
10
0*
50 79 2421 3,24 20
N 50/10 - 0 3
0,5%* N 50/10 - 0,5/M 3
1,0 %* N 50/10 - 1/M 3
0,5%+0,5%* N 50/10 - 1/M+m 3
1%+1% N 50/10 - 2/M+m 3
10
0*
80 79 6321 1,24 35
N 80/10 - 0 2
0,5%* N 80/10 - 0,5/M 3
1,0 %* N 80/10 - 1/M 3
0,5%+0,5%* N 80/10 - 1/M+m 3
1%+1% N 80/10 - 2/M+m 3
20
0*
100 314 9686 3,24 40
N 100/20 - 0 3
0,5%* N 100/20 - 0,5/M 3
1,0 %* N 100/20 - 1/M 3
0,5%+0,5%* N 100/20 - 1/M+m 3
1%+1% N 100/20 - 2/M+m 3
20
0*
150 314 22186 1,41 65
N 150/20 - 0 3
0,5%* N 150/20 - 0,5/M 3
1,0 %* N 150/20 - 1/M 3
0,5%+0,5%* N 150/20 - 1/M+m 3
1%+1% N 150/20 - 2/M+m 3
30
0*
150 707 21793 3,24 60
N 150/30 - 0 3
0,5% N 150/30 - 0,5/M 3
1,0 % N 150/30 - 1/M 3
0,5%+0,5% N 150/30 - 1/M+m 3
1%+1% N 150/30 - 2/M+m 3
30
0*
200 707 39293 1,80 85
N 200/30 - 0 2
0,5% N 200/30 - 0,5/M 3
1,0 % N 200/30 - 1/M 3
0,5%+0,5% N 200/30 - 1/M+m 3
1%+1% N 200/30 - 2/M+m 3
Bar diameter f=10 mm
Bar diameter f=20 mm
Bar diameter f=30 mm
50
50
80
80
150
15
0
95
0
11
50
100
10
0
150 200
15
0
20
0
Reinforcement
b
Varia
tion o
f the re
bar d
iam
ete
rVariation of the specimen
size, b
Variation of the longitudinal
steel ratio, ρ=3,24% to 1,24%
Varia
tion o
f the re
bar d
iam
ete
r
Experimental Program
11/60 Göteborg, Sweden, September 13, 2017
Experimental program
1st phase: tie 950/1000 mm long tested in by means of a
hydraulic servo-controlled (closed-loop) testing machine with
MTS control
2nd phase: tie 1000 mm
and 1500 long tested in
by means of a available
steel reacting frame
conveniently modified
12/60 Göteborg, Sweden, September 13, 2017
Instrumentation
13/60 Göteborg, Sweden, September 13, 2017
Fiber types and contents
Fibre IDType of
steelShape
fuf[MPa]
Lf [mm]
f[mm]
Lf /f [-] Batch ID
30/0.62 Carbon Hooked-end 1270 30 0.62 48.39 0.5M, 1M, 1M+m
13/0.20High
carbonStraight 2000 13 0.20 65.0 1M+m
Batch ID Fibers 30/0.62Fibers13/0.20
Vf,tot
0 Plain - - -
0.5M 0.5 - 0.5
1M 1 - 1
1M+m 0.5 0.5 1
14/60 Göteborg, Sweden, September 13, 2017
FRC properties
3PBTs on notched beams according to EN14651:
Fracture parameters of the SFRCs according to EN-14651
Batch ID fLm [MPa] fR1m [MPa] fR2m [MPa] fR3m [MPa] fR4m [MPa]
1st
phase
0.5M 5.46 5.00 4.55 4.05 3.46
1M 4.81 5.09 4.12 3.42 3.01
1M+m 5.97 6.30 5.35 4.35 3.54
2nd
phase
0.5M 4.60 4.12 4.07 3.35 2.69
1M 4.64 5.43 4.89 4.36 3.86
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
0.0 1.0 2.0 3.0 4.0
No
min
al
stre
ss
N[M
Pa
]
CMOD [mm]
3PBT - EN - 14651
SFRC 0.5M
SFRC 1M
15/60 Göteborg, Sweden, September 13, 2017
0
20
40
60
80
100
120
140
160
180
200
0 1 2 3 4 5
Ax
ial
forc
e [
kN
]
Average member strain, sm [‰]
Specimens 120x120 - Φ20 - ρ = 2.23%
Bare bar Φ20
N 120/20 - 0
N 120/20 - 0.5M
Crack formation and development
The typical response terms of axial load vs. average tensile strain of RC and FRC
FRC stiffens the response of tensile tie with respect to non-fibrous members
By referring to a certain axial force the average strain (εsm) reduces by adding fibres
-
0
50
100
150
200
250
300
350
400
450
500
0 1 2 3 4 5
Axia
l fo
rce [
kN
]
Average member strain, sm [‰]
Specimens 200x200 - Φ30 - ρ= 1.80%
Bare bar Φ30
N 200/30 - 0
N 200/30 - 0.5M
+N
16/60 Göteborg, Sweden, September 13, 2017
Crack formation and development
Plain Concrete FRC
Fibre addition determines a reduction of the mean crack spacing
17/60 Göteborg, Sweden, September 13, 2017
Crack width and crack spacing
Crack spacing evolution vs. average member strain
0
100
200
300
400
500
600
700
800
0.0 0.5 1.0 1.5 2.0 2.5 3.0
Cra
ck s
paci
ng [
mm
]
Average member strain, sm [‰]
Specimens 200x200 - Φ30 - ρ= 1.80%
RC
SFRC 0.5M
SFRC 1M
Final crack spacing
18/60 Göteborg, Sweden, September 13, 2017
Crack width and crack spacing
The residual FRC post-cracking strength improves the behaviour at SLS and the durability of structures for two main reasons:
1) determines a global stiffer response of the tensile tie which means, by referring
to a certain axial tensile force, a reduction of sm;
2) implies a reduction of the mean crack spacing (srm).
cmsmrmm
sw
Reduction of the mean crack width, wm
19/60 Göteborg, Sweden, September 13, 2017
Crack width
-53% -56%
-32% -29%
-39% -41%
-29% -23%
-16% -28%
-12% -32%
-33% -38%
-25% -40% -31% -36%
Crack opening reduction with respect to plain samples (RC)[%]
Average reduction fibre SFRC 0.5M - 30,0%
Average reduction fibre SFRC 1M - 35,8%
Mean crack width at SLS comparison (@ average strain = 1*10-3)
Mea
n c
rack
wid
th [m
m]
SFRC 0.5M
Plain (RC)
SFRC 1M+m
SFRC 1M
20/60 Göteborg, Sweden, September 13, 2017
Mean and minimum crack spacing
Mean crack spacing (srm) and minimum crack spacing (sr,min) comparison
0
50
100
150
200
250
300
350
400
0 500 1000 1500 2000 2500
Mea
n c
ra
ck s
pa
cin
g [
mm
]
Φ/ρeff [mm]
Mean crack spacing vs. Φ/ρeff
RC
SFRC Vf=0.5%
SFRC Vf=1%
100x100 Φ20
120x120 Φ20
180x180 Φ30
200x200 Φ30
180x180 Φ20
150x150 Φ20
50x50 Φ10
80x80 Φ10
150x150 Φ30
R2=0.92
R2=0.76
R2=0.93
srm = 1.18srmin
R2 = 0.92srm= 1.40srmin
R2 = 0.91srm = 1.45srmin
R2 = 0.86
0
50
100
150
200
250
300
350
400
450
500
0 50 100 150 200 250 300 350
Mean
crack
sp
aci
ng [
mm
]
Minimum crack spacing [mm]
Mean crack spacing vs. minimum crack
spacingRC
SFRC Vf=0.5%
SFRC Vf=1%
Mean crack spacing (srm) reduction of around 30% (Vf=0.5%) and 37% (Vf=1%)
Similar ratio between mean crack spacing and minimum crack spaing: RC vs. SFRC ties
21/60 Göteborg, Sweden, September 13, 2017
Crack spacing
Mean crack spacing (srm) vs. fR1m
0
50
100
150
200
250
300
3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5
Mea
n c
ra
ck s
pa
cin
g [
mm
]
fR1m [MPa]
Mean crack spacing vs. fR1m - SFRC series
Vf<1%
Φ/ρ<500
500<Φ/ρ<1000
1000<Φ/ρ<1500
Φ/ρ>1500
An increase in the residual strength fR1m leads to a decrease of srm
22/60 Göteborg, Sweden, September 13, 2017
Crack spacing in the building codes
The main results in terms of mean crack spacing (srm) are compared with the predictions obtained by the following formulations:
eff,s
21rmkk
10
sc2s
eff,s
rm6.3
1
3
2s
ctmbm
eff,s
rmf8.1:termshort
8.1
1
4
1c17.1s
Regarding FRC:
m1RFtsm
ctmbm
eff,sbm
Ftsmctm
m,r
f45.0f
f8.1:termshortff
4
1c17.1s
- Model Code 1978:
- Model Code 1990:
- Model Code 2010:
- Model Code 2010(final draftfib bulletin 65/66) fR1m,
parameter according to EN14651:
- RILEM TC 162-TDF:
ffeffs
mrL
KKs
/
5025.050
,
21,
- Model Code 2010(first draftfib bulletin 55/56)
mRFtsm
effsbm
Ftsmctmmr
ff
ffs
1
,
,
45.0
4
117.1
145.0 RFts ff
23/60 Göteborg, Sweden, September 13, 2017
Crack spacing
Plain series (RC): prediction of mean crack spacing, MC1978 & MC1990
0
50
100
150
200
250
300
350
400
450
500
0 100 200 300 400 500
Mean
crack
sp
aci
ng (
measu
red
)[m
m]
Mean crack spacing (predicted)[mm]
Prediction of the mean c.spacing- RC series
MC1978
MAPE=24.7%
0
50
100
150
200
250
300
350
400
450
500
0 100 200 300 400 500M
ean
crack
sp
aci
ng (
measu
red
)[m
m]
Mean crack spacing (predicted)[mm]
Prediction of the mean c.spacing- RC series
MC1990
MAPE=17.1%
CONSERVATIVE
UN
CO
NS
ER
VA
TIV
E
CONSERVATIVE
UN
CO
NS
ER
VA
TIV
E
MC 1978 MC 1990
24/60 Göteborg, Sweden, September 13, 2017
Crack spacing
Plain series (RC): prediction of mean crack spacing, MC 2010
0
50
100
150
200
250
300
350
400
450
500
0 100 200 300 400 500
Mea
n c
ra
ck
sp
acin
g (
mea
sure
d)[
mm
]
Mean crack spacing (predicted)[mm]
Prediction of the mean c.spacing- RC series
MC2010,
Final draft
MAPE=24.0%
UN
CO
NS
ER
VA
TIV
E
CONSERVATIVE
MC 2010
25/60 Göteborg, Sweden, September 13, 2017
Crack spacing
SFRC series: prediction of mean crack spacing, RILEM TC-162-TDF
0
50
100
150
200
250
300
0 50 100 150 200 250 300
Mea
n c
ra
ck s
pa
cin
g (
mea
sure
d)[
mm
]
Mean crack spacing (predicted)[mm]
Prediction of the mean c.spacing - SFRC series
RILEM TC 162-TDF
MAPE@100%CONSERVATIVE
UN
CO
NS
ER
VA
TIV
E
RILEM
26/60 Göteborg, Sweden, September 13, 2017
Crack spacing
SFRC series: prediction of mean crack spacing, MC 2010 Final draft
0
50
100
150
200
250
300
0 50 100 150 200 250 300
Mea
n c
rack
sp
aci
ng
(m
easu
red
)[m
m]
Mean crack spacing (predicted)[mm]
Prediction of the mean c.spacing - SFRC series
MC2010, Final draft
MAPE=27.9%CONSERVATIVE
UN
CO
NS
ER
VA
TIV
E
MC 2010
Final Draft
27/60 Göteborg, Sweden, September 13, 2017
Crack spacing
SFRC series: prediction of mean crack spacing, MC 2010 First draft
0
50
100
150
200
250
300
0 50 100 150 200 250 300
Mea
n c
ra
ck s
pa
cin
g (
mea
sure
d)[
mm
]
Mean crack spacing (predicted)[mm]
Prediction of the mean c.spacing - FRC series
MC2010, First Draft
MAPE=65.8%
CONSERVATIVE
UN
CO
NS
ER
VA
TIV
E
MC 2010
First Draft
28/60 Göteborg, Sweden, September 13, 2017
Durability requirements in building codes
Durability in EN-206
29/60 Göteborg, Sweden, September 13, 2017
Cracking vs. Durability
Durability
Possible solution for improving crack control: Fibre Reinforced
Concrete (FRC)
Between two cracks At crack location
Lower porosity Lower crack width
W/C ratio
30/60 Göteborg, Sweden, September 13, 2017
Corrosion at crack location
Is crack control important for durability?
31/60 Göteborg, Sweden, September 13, 2017
Simulated pitting corrosion
CUTTER DIAMETERS:
8 mm
12 mm
16 mm
20 mm
32/60 Göteborg, Sweden, September 13, 2017
senR
senR
AAAp
asp
22
22
21.
CFBCBFh
2cos1
RCGRBC
2cos1
PP
RCARCF
2cos1
2cos1
p
RRh
2cos1
2senarcsencos1
p
pR
R
RRh
D
Dp
C
F
E
B
A
G
h
RpRp
A2
A1
known:
-Dp = cutter diameter
-Dnom = nominal bar diameter
Simulated pitting corrosion
33/60 Göteborg, Sweden, September 13, 2017
Simulated corrosion
INSTRUMENTATION
la
la
l0 la+l0
34/60 Göteborg, Sweden, September 13, 2017
Material properties
Diam. fsy fst
[mm] [MPa] [MPa]
12 526 613
16 513 606
20 ls 491 570
20 ms 534 610
20 hs 550 628
24 555 597
Experimental program
35/60 Göteborg, Sweden, September 13, 2017
Diameter=12 mm - Dr=8 mm
0
10
20
30
40
50
60
70
80
0 2 4 6 8 10 12Displacement [mm]
Load [
kN
]
%=0.95
%=0.90
%=0.8
%=0.7
%=0.6
%=0.5
Load vs. Displacement curves
36/60 Göteborg, Sweden, September 13, 2017
Bar diameter = 12 mm
0
1
2
3
4
5
6
7
8
0.4 0.5 0.6 0.7 0.8 0.9 1 1.1
%Ares
Dis
pla
cem
ent
d0.9
9 [
mm
]
Undamaged Bar
Dr=10 mm
Dr=8 mm
Dr=6 mm
Dr=4 mm
Bar diameter = 16 mm
0
2
4
6
8
10
12
0.4 0.5 0.6 0.7 0.8 0.9 1 1.1
%Ares
Dis
pla
cem
ent
d0.9
9 [
mm
]
Dr = 10 mm
Dr = 8 mm
Dr = 6 mm
Dr = 4 mm
Bar diameter = 20 mm
0
2
4
6
8
10
12
14
16
0.4 0.5 0.6 0.7 0.8 0.9 1 1.1%Ares
Dis
pla
cem
ent
d0.9
9 [
mm
] High S tre ngth
Me dium S tre ngth
Low S tre ngth
Bar diameter = 24 mm
0
2
4
6
8
10
12
0.4 0.5 0.6 0.7 0.8 0.9 1 1.1
%Ares
Dis
pla
cem
ent
d0
.99 [
mm
]
Unda ma ge d Ba r
Dr=10 mm
Dr=8 mm
Dr=6 mm
Dr=4 mm
Ultimate displacement
37/60 Göteborg, Sweden, September 13, 2017
Exposure in aggressive (marine) environment
10 beams has been exposed for more than 2 years in a coastal zone,
under a load equal to 50% of the ultimate load
Aim of the research: evaluate the influence of fibers on mechanical
behaviour of FRC in short and long term bending test
38/60 Göteborg, Sweden, September 13, 2017
Beam geometry and rebar properties
3Ø14 18
2 Ø14
18
300
25
294
25
25
7 7
10
14 14
10
294
3
3
52
DiameterYield strength
(MPa)
Ultimate strength
(MPa)
Longitudinal
bars14mm 520 614
Stirrups 8mm 567 600
39/60 Göteborg, Sweden, September 13, 2017
FRC properties
(UNI 11039)
0 500 1000 1500 2000
0
2
4
6
8
10
12
06S
09P
TQ065
LO
AD
(kN
)
CTOD (microns)
0.6% steel
0.9% polyester
Vf=0,6%
Vf=0,9%
40/60 Göteborg, Sweden, September 13, 2017
Crack monitoring
Crack width, crack length and
crack position have been
measured during the exposure
period. The crack width has been
measured with a digital
microscope (200x magnification)
41/60 Göteborg, Sweden, September 13, 2017
Cracking monitoring
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0 50 100 150 200 250
pp1
pp2
st1
st2
tq
In FRC beams the crack widths were in the range of 0.1 to 0.2 mm, without overcome the
threshold of 0.2 mm. In plain beam the 93.3% of cracks had a crack width over 0.1 mm, while
the 60% over 0.2 mm.
42/60 Göteborg, Sweden, September 13, 2017
Cracking monitoring
Average of crack widths between the loading points
Beams Dw /%
ST1-2_E 54%
POL1-2_E 53%
0.31
0.14 0.140.16
0.13
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
TQ1_E ST1_E ST2_E POL1_E POL2_E
Cra
ck w
idth
(m
m)
Crack width reduction of the FRC beams respect
to the plain beam (Dw /%).
steel polyester
PC
43/60 Göteborg, Sweden, September 13, 2017
Cracking behavior at SLS
SLE
(50kN)
ST1-2 35%
POL1-2 28%
SHORT TERM
BEAMS
LONG TERM
BEAMS
SLE (50kN)
ST1-2_E 43%
POL1_E 37%
POL2_E 43%
Crack width reduction of the FRC beams respect to the plain beam.
44/60 Göteborg, Sweden, September 13, 2017
Cracking behavior at ULS
SLU
(100kN)
ST1-2_E 56%
POL1_E 25%
POL2_E 54%
SLU
(100kN)
ST1-2 41%
POL1-2 39%
Crack width reduction of the FRC beams respect to the plain beam.
SHORT TERM
BEAMS
LONG TERM
BEAMS
45/60 Göteborg, Sweden, September 13, 2017
Carbonation depth
CARBONATION DEPTHCHLORIDE CONTENT
46/60 Göteborg, Sweden, September 13, 2017
Carbonation depth between the cracks
47/60 Göteborg, Sweden, September 13, 2017
Carbonation depth at cracks
K
(mm/anni
^0.5)
t
armature
(anni)
TQ_E 19.4 2.4
ST1_E 12.7 5.6
ST2_E 13.4 5.0
POL1_E 12.5 5.8
POL2_E 14.7 4.2
48/60 Göteborg, Sweden, September 13, 2017
Concluding remarks
FRC diffusely influence the behavior of tension-ties at serviceability limit states, by
reducing crack width and determining a crack patterns with narrower and well
closely spaced cracks;
SFRC positively influences the behaviour of tension-ties at SLS due to two main
aspects: tension-stiffening significantly increases and mean crack spacing
(srm) reduces with respect to the RC members (without fibres)
Lower crack widths due to FRC involve a consistent increase in the structural
durability and, therefore, in the structural life;
The MC 2010 model for predicting srm in FRC elements generally predicts with
sufficient accuracy the experimentally observed data;
SFRCs having fR1m around 4-5 MPa were mainly investigated: further studies
regarding SFRCs with different post-cracking strengths (higher or lower) could
be developed
49/60 Göteborg, Sweden, September 13, 2017
Open issues
Transform cracking information in durability
issues in order to guarantee the structural
safety for the whole service life of the
structure.
In this context, FRC is a valuable tool for
enhancing structural durability!
50/60 Göteborg, Sweden, September 13, 2017
Papers in international journal
Minelli, F., Tiberti, G., and Plizzari, G.A. (2011). “Crack Control in RC Elements with
Fiber Reinforcement”, paper ID: SP-280-6; ACI Special Publication ACI SP-280:
Advances in FRC Durability and Field Applications CD-ROM, Vol. 280, Editors:
Corina-Maria Aldea & Mahmut Ekenel, December 2011, pp. 76-93. ISBN 0-87031-
751-2 and/or 978-0-87301-751-4.
Tiberti, G., Minelli, F., Plizzari, G.A., Vecchio, F.J. (2014). “Influence of concrete
strength on crack development in SFRC members”, Cement and Concrete
Composites, Vol. 45, January 2014, ISSN: 0958-9465, pp. 176-185,
doi:http://dx.doi.org/10.1016/j.cemconcomp.2013.10.004.
Tiberti, G., Minelli, F., Plizzari, G. (2015). “Cracking behavior in reinforced concrete
members with steel fibers: A comprehensive experimental study”, Cement and
Concrete Research, Vol. 68, February 2015, ISSN: 0008-8846, pp. 24-34, doi:
http://dx.doi.org/10.1016/j.cemconres.2014.10.011.
51/60 Göteborg, Sweden, September 13, 2017
Papers in international journal
Vasanelli E., Micelli F., Aiello M.A., Plizzari G. (2013), Long term behavior of FRC
flexural beams under sustained load, Engineering Structures, Volume 56, pp. 1858-
1867.
Emilia Vasanelli, Francesco Micelli, Maria Antonietta Aiello, Giovanni Plizzari (2013),
Crack width prediction of FRC beams in short and long term bending condition,
Materials and Structures, Springer, pp. 1-16.
Cairns, J., Plizzari, G. A., YINGANG, D., Law, D. W., & Franzoni, C. (2005).
Mechanical properties of corrosion-damaged reinforcement. ACI Materials Journal,
102(4), 256-264.
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About Brescia
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Historical buildings in Brescia
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Dolomites
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Dolomites
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Lake Garda
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Welcome to Brescia
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Workshop proceedings
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Desenzano, June 28-30, 2018
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Thank you for your kind
attention!
University of Brescia, Italy
Göteborg, Sweden, September 13, 2017
G. Plizzari
University of Brescia, Italy
Cracking and durability
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Experimental program
Prismatic SFRC samples with a central rebar: SFRC tension tie
Bar diameter
=10 mm
Bar diameter
=20 mm
Bar diameter
=30 mm
505
080
80
1501
50
L=
95
0
11
50
100
10
0
150 200
15
0
20
0
Reinforcement
b
Variation of the
specimen size, b
Variation of the longitudinal
steel ratio =3.24% to 1.24%
Variatio
n o
f the
rebar d
iameter
80
80
Variation of the longitudinal
steel ratio =0.98% to 2.23%
200
20
0
120
12
0
180
18
0
180
18
0
Variation of the
specimen size, b
30
03
00
b
(a) (b)
1st phase 2nd phase
L=
15
00
(L
=1
00
0 f
or
10
bar
)
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