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Research on the Abrasion Erosion and Impact Resistance of Fiber Concrete
Wu, C.
Department of Civil Engineering, National Chung-Hsing University
(email: hubert.woo@yahoo.com.tw)
Liu, Y.
Department of Civil and Water Resources Engineering, National Chiayi University
(email: yuwen@mail.ncyu.edu.tw)
Huang, C.
Department of Civil Engineering, Dahan Institute of Technology
(email: cdewsx.hch@gmail.com)
Yen, T.
Department of Civil Engineering, National Chung-Hsing University
(email: tyen@dragon.nchu.edu.tw)
Hsu, t.
Department of Construction, Taipower Company
(email: u787200@taipower.com.tw)
Abstract
The damage mode of the concrete surface of hydraulic structures mainly depends on the structure
configuration formations and the environmental conditions. It is impossible to prevent the hydraulic
concrete structures from damaging by abrasion erosion and impact of waterborne particles. The
research aims to investigate adequate repair materials which could be applied in the repair for the
surface layer of hydraulic structures. A new developed flow abrasion test apparatus was developed
for test to simulate the abrasion erosion of concrete that takes place in site. Besides, Standard Test
Method for Abrasion Resistance of Concrete (ASTM C1138) and Measurement of Properties of
Fiber Reinforced Concrete (ACI committee 544) were also adopted in the test. Three kinds of fibers,
carbon fiber, glass fiber and steel fiber, were added respectively in the concrete to prepare the
specimens. Test results show that the steel fiber concrete performed better abrasion erosion
resistance than that of the carbon fiber concrete and glass fiber concrete when the fiber content keeps
1.0 %. It was found from the underwater abrasion test that the carbon and the glass fiber concrete
demonstrate quite similar abrasion erosion resistance, while the steel fiber concrete exhibits the best
abrasion resistance, its average abrasion volume is 20 % lower than that of the other two fiber
concretes. It was also found from the crack impact test that for the concrete containing 1.0 % fiber
the glass fiber concrete can present the best impact resistance, subsequent by the carbon fiber
concrete, and the steel fiber concrete is the worst.
Keywords: hydraulic structure, fiber concrete, abrasion erosion, impact resistance
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1. Introduction
Yen (2000), Hsu (2006) and Webster (1987) pointed that it is impossible to prevent the hydraulic
concrete structures from damaging by abrasion erosion and impact of waterborne particles. Using the
best quality of concrete surface can merely extend the service life or reduce the repair frequency of
hydraulic structures. Hence, the research intends to investigate a technique of using fiber concrete in
hydraulic structures to extend their service life.
ACI 210R-93 (Erosion of Concrete in Hydraulic Structures) defined the damage molds of the
concrete surface of hydraulic structures as erosion by cavitation, erosion by abrasion and erosion by
chemical attack. The abrasion erosion is caused mainly by erosion, abrasion and impact actions.
Erosion appears in places where rushing stream could reach, the range of erosion is wide but the
damage of erosion is less. Abrasion only appears in an active bed-load area, the damage of abrasion
appears generally in spillway aprons, stilling basins, sluiceways, drainage conduits and tunnel linings.
Impact appears mainly in the concrete surface of the bend of the watercourse due to striking by rock.
Papenfus (2003), Liu (1981) and Laplante (1991) assessed that the compressive strength of concrete
has a high relation to abrasion erosion resistance, namely, the abrasion erosion resistance of concrete
increases by increasing the compressive strength of concrete. Besides, Liu (1981), Laplante (1991)
and Liu (2006) reported that the water-to-cement ratio is an important factor to evaluate the abrasion
erosion resistance of concrete. The quality, type and properties of coarse aggregate have an obvious
influence on the abrasion erosion resistance. Liu (1981) investigated the abrasion erosion resistance
of eight kinds of coarse aggregates by ASTM C1138 method (underwater method). The test results
indicated that the abrasion erosion resistance of concrete enhances by increasing the hardness of
coarse aggregates when the water-to-cement ratio and compressive strength keep constants. Liu
(2006) reported that the concrete containing silica fume has better abrasion erosion resistance.
Adding fibers in concrete can enhance the toughness and brittleness of concrete. Bayasi (1993)
indicated that the cracks in the fiber concrete are blocked and prevented the crack from further
development because that the fibers could absorb the deformation energy of concrete and thus benefit
the concrete’s ductility. Such that, this research aims to investigate the abrasion erosion and impact
resistance of fiber concretes using a new developed flow abrasion test apparatus.
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2. Test Program
2.1 Material
1. Cement (C): Type I portland cement (ASTM C 150).
2. Silica Fume (SF): meets the requirements of ASTM C 1240.
3. Blast furnace slag (BFS): the property meets the requirements of ASTM C 989.
4. Fine Aggregate (FA): the specific gravity is 2.62, fineness modulus is 3.01.
5. Coarse Aggregate (CA): the specific gravity is 2.63, maximum size is 20 mm.
6. Carbon Fiber (CF): the specific gravity is 1.8, the physical properties as showed in Table 1.
7. Glass Fiber (GF): the specific gravity is 2.78, the physical properties as showed in Table 2.
8. Steel Fiber (SF): the diameter is 0.25 mm, the length is 13 mm, the tension strength is 2000
kgf/cm3, the ratio of length-to-diameter is 52.
9. Superplasticizer (SP): meets the requirements of ASTM G-Type1. PH = 2.5, specific gravity =
1.07, solid component = 40.22 %
Table 1: Physical Property of Carbon Fiber
Carbon Fiber Number of Each Filament 12,000
Unit Weight 0.82 g/m
Diameter 7 μ
Specific Gravity 1.8
Strength 352 kg/mm2
Elastic Modulus 23,000 kg/mm2
Table 2: Physical Property of Glass Fiber
ZrO2 14.5 %
Elongation Ratio of Strain At Break Point 3.0 %
Young s Modulus 69580 MPa
Specific Gravity 2.78
Absorption < 0.2 %
Melting Point 800 °C
Diameter 16 μm
Lose Weight Ratio in the liquid of NaOH for 100 ℃ after 1 hour < 5 %
Residual Strength in the liquid of NaOH for 100 ℃ after 4 hour >82 %
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2.2 Experiment variables and mixture proportion
Test variables as shown in Tables 3 and 4 include the content of carbon fiber (1.0 %), glass fiber (0.5
%, 1.0 %, 1.5 %) and steel fiber (0.5 %, 1.0 %, 1.5 %). The water-binders ratio is 0.28. Table 5 gives
the mixture proportions of concrete sample, in which the proportion of binder materials, Cement:
Blast Furnace Slag: Silica Fume (C: SL: SF), is 7: 1: 2.
Table 3: Test plan
W/B Concrete types Test item Test age (day)
0.28
Carbon fiber concrete
Glass fiber concrete
Steel fiber concrete
Flow abrasion tes t
Abrasion underwater test (ASTM C1138)
Cracking impact test (ACI committee 544)
28, 56
Table 4: Test variables a)
W/B Mix
number
Water Cement C:SL:SF
Fiber SP Sand ratio Aggregate
kg/m3 %
0.28
CF10 140 350 7:1:2 1.0 1.5 40 39
GF05 140 350 7:1:2 0.5 1.5 40 39
GF10 140 350 7:1:2 1.0 1.5 40 39
CF15 140 350 7:1:2 1.5 1.5 40 39
SF05 140 350 7:1:2 0.5 1.5 40 39
SF10 140 350 7:1:2 1.0 1.5 40 39
SF15 140 350 7:1:2 1.5 1.5 40 39
a): CF = Carbon Fiber; GF = Glass Fiber; SF = Steel Fiber; SL = Blast Furnace Slag;
SF = Silica Fume; SP = Superplasticizer
Table 5: Mixture proportion of fiber concrete (kg/m3)
Mix
number W/B Water Cement BFS SF Fiber Sand FA CA SP Air
CF10 0.28 140 350 50 100 18 711 516 518 7.5 1%
GF05 0.28 140 350 50 100 14 717 520 522 6.0 1%
GF10 0.28 140 350 50 100 28 711 516 518 7.5 1%
GF15 0.28 140 350 50 100 42 706 511 513 8.5 1%
SF05 0.28 140 350 50 100 39 718 520 522 5.0 1%
SF10 0.28 140 350 50 100 78 712 516 518 6.5 1%
SF15 0.28 140 350 50 100 117 706 512 514 7.5 1%
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2.3 Experimental program and apparatus
1. Flow abrasion test: The apparatus as shown in Figure 1 is designed specially to evaluate the
abrasion erosion resistance of concrete surface subjected to impact of waterborne sand. There are
four motors, a motor revolves a blade, fixed in four corners of the apparatus. Using a water pump
to circulate the waterborne sand, then the blades mixes well the waterborne sand, and the speed of
the flow is kept at 12m/s. A designed fabricated 10 x 200 mm rectangular nozzle is large enough
to cover the maximum size of waterborne sand. The dimension of fiber concrete specimens is 200
x 200 x 50 mm and the total test period is two hours. The relative abrasion erosion resistance is
evaluated by weight loss of concrete specimen.
2. Abrasion resistance test of concrete underwater method: The test apparatus as shown in Figure
2 is formulated according to ASTM C1138. A steel pipe with a chuck capable of holding and
rotating the agitation paddle with steel balls under test conditions at a speed of 1200 ± 100 rpm is
used. The apparatus was used to measure the abrasion resistance underwater of concrete
specimens. The dimension of specimen is Φ300 x 100 mm and the test specimens are weighed at
12 hours intervals during the 48 hours test period. The abrasion erosion resistance is also
evaluated by weight loss of concrete specimens.
3. Crack impact test: Figure 3 shows the conformation of the apparatus. It is designed according to
ACI committee 544. A disc specimen rests on the base plate within four positioning lugs. By
testing, a hammer consecutively falls from a height onto a steel ball standing at the center of the
disc, subjecting the disc to repeated impact blows. The specimen size is Φ150 x 63.5 mm in
dimension and the test time ends until the destroyed stage (finial-cracking) of specimens appears.
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0 m
m
300 mm
44
0 m
m
Water Drainage Valve
Steel Grinding Balls
Specimen
Seating Blocks
Concrete Specimen
Steel Tank
Agitation Paddle
Screw W/Wing
Nut
20 mm
100 mm
40 mm
130mm
60 mm
Water Pump
Mixing Pump
Specimen
Mixture
Dire
ctio
n o
f Wate
r Flo
w
Shotcrete
Nozzle
11
50
mm
1295 mm
30
0 m
m
Figure 1: Schematic of flow abrasion test
apparatus
Figure 2: Schematic of abrasion underwater
apparatus
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Figure 3: Schematic of cracking impact apparatus
3. Results and discussion
3.1 Abrasion Erosion Resistance of Fiber Concrete
3.1.1 Results obtained from flow abrasion test
Table 6 summarizes the test results of fiber concrete subjected to flow abrasion erosion test with
water containing 230 kg/m3 sand. Figures 4 and 5 show the relationship between abrasion erosion
resistance of the glass and steel fiber concretes. It may be found that the fiber concrete containing
various fiber amount of 0.5 % to 1.5 %, at age of 28 days and 56 days, exhibit almost the similar
abrasion loss of mass. This implies that the fiber contents have insignificant effects on the abrasion
erosion resistance of fiber concrete.
Figure 6 shows the abrasion volume after 48 hours abrasion test of three fiber concretes with 1.0 %
fiber content. It may be seen that the abrasion volume of the three fiber concretes with carbon fiber,
glass fiber and steel fiber at 28 days age are 19.9 cm3/hr, 21.2 cm
3/hr and 18.4 cm
3/hr, respectively,
and at 56 days age are 14.0 cm3/hr, 12.5 cm
3/hr and 7.5 cm
3/hr, respectively. It reveals that when the
age of fiber concretes increase from 28 days to 56 days, the abrasion volume decrements of the three
fiber concretes reduce approximately 30 %, 42 % and 60 %, respectively. Consequently, the steel
fiber concrete exhibits better abrasion erosion resistance in relation to the other fiber concretes.
45
7 m
m
Concrete Specimen
(64mm thick)
Hammer (4.5kg)
Steel Ball
(63.5mm diameter)
338
Table 6: Abrasion loss of mass of fiber concrete from flow abrasion test (cm3/h)
Mix number 28 day 56 day
CF10 19.9 14.0
GF05 21.6 12.4
GF10 21.2 12.5
GF15 21.1 11.8
SF05 18.2 7.6
SF10 18.4 7.5
SF15 16.9 7.2
Figure 6: Abrasion volume of fiber concrete from flow abrasion test
Figure 4: Relationships between abrasion
loss of mass and glass fiber
content
Figure 5: Relationships between abrasion
loss of mass and steel fiber
content
0.4 0.8 1.2 1.6Content (%)
0
5
10
15
20
25
Abr
asio
n lo
ss o
f mas
s (c
m3 /h
)
Glass Fiber28 day56 day
0.4 0.8 1.2 1.6Content (%)
0
5
10
15
20
25
Abr
asio
n lo
ss o
f mas
s (c
m3 /h
)
Steel Fiber28 day56 day
0
5
10
15
20
25
CF10 GF10 SF10
48
h T
ota
l A
bra
sio
n V
olu
me
(cm
3)
28 day
56 day
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3.1.2 Results obtained from underwater abrasion test (ASTM C1138)
Table 7 and 8 summarize the average accumulating abrasion volume of fiber concrete at various test
times for the concrete age of 28 and 56 days. Figures 7 to 10 plot the average abrasion volume of
glass and steel fiber concretes against the time. It may be found that the abrasion volumes increase by
the increase of test time, the increment of abrasion volume for both of glass and steel fiber concretes
appear a linear increasing. It means that the abrasion volume of glass and steel fiber concretes is
similar at every 12 hours test interval. Hence, both the fiber concretes demonstrate a stable abrasion
resistance when the abrasion energy keeps constant.
Figures 11 and 12 present the abrasion volume of the three fiber concretes in relation to the test
times. It could be seen that the carbon and glass fiber concretes exhibit quite similar abrasion erosion
resistance, while the steel fiber concrete shows the best abrasion erosion resistance, its average
abrasion volume is 20 % lower than that of the other two fiber concretes. It is due to the reason that,
by underwater abrasion test, the greater steel fiber could be perform as hardened aggregate in
concrete, resulting in advantageous to the abrasion resistance.
Table 7: Abrasion volume of fiber concrete from underwater abrasion test (28 day)
Average of accumulating abrasion volume (cm3)
Mix number Test time (h)
0 12 24 36 48
CF10 0 8.3 18.8 28.6 39.4
GF05 0 8.9 19.8 29.7 41.0
GF10 0 7.6 17.3 26.3 37.1
GF15 0 11.2 22.3 32.1 43.2
SF05 0 7.3 14.1 22.7 30.9
SF10 0 6.6 13.2 21.6 30.6
SF15 0 5.9 12.3 20.7 29.7
Table 8: Abrasion volume of fiber concrete from underwater abrasion test (56 day)
Average of accumulating abrasion volume (cm3)
Mix number Test time (h)
0 12 24 36 48
CF10 0 8.3 16.6 25.6 34.8
GF05 0 8.2 17.3 27.8 39.1
GF10 0 8.7 17.2 25.3 34.5
GF15 0 9.5 17.7 26.8 35.8
SF05 0 6.2 13 20.7 28.2
SF10 0 6.2 12.6 19.7 26.8
SF15 0 5.2 11.7 18.6 25.2
340
Figure 7: Abrasion volume of glass fiber
concrete vs. test time (28 day)
Figure 8: Abrasion volume of steel fiber
concrete vs. test time (28 day)
Figure 9: Abrasion volume of glass fiber
concrete vs. test time (56 day)
Figure 10: Abrasion volume of steel fiber
concrete vs. test time (56 day)
Figure 11: Abrasion volume of fiber concretes
vs. test time (28 day)
Figure 12: Abrasion volume of fiber concretes
vs. test time (56 day)
0 10 20 30 40 50Age (hour)
0
10
20
30
40
50
48h
Abr
asio
n E
rosi
on V
olum
e (c
m3 )
Glass Fiber0.5%1.0%1.5%
0 10 20 30 40 50Age (hour)
0
10
20
30
40
50
48h
Abr
asio
n E
rosi
on V
olum
e (c
m3 )
Steel Fiber0.5%1.0%1.5%
0 10 20 30 40 50Age (hour)
0
10
20
30
40
50
48h
Abr
asio
n E
rosi
on V
olum
e (c
m3 )
Glass Fiber0.5%1.0%1.5%
0 10 20 30 40 50Age (hour)
0
10
20
30
40
5048
h A
bras
ion
Ero
sion
Vol
ume
(cm
3 )
Steel Fiber0.5%1.0%1.5%
0 10 20 30 40 50Age (hour)
0
10
20
30
40
50
48h
Abr
asio
n E
rosi
on V
olum
e (c
m3 )
Fiber Content = 1.0%Carbon FiberGlass FiberSteel Fiber
0 10 20 30 40 50Age (hour)
0
10
20
30
40
50
48h
Abr
asio
n E
rosi
on V
olum
e (c
m3 )
Fiber Content = 1.0%Carbon FiberGlass Fiber Steel Fiber
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3.2 Impact Resistance of Fiber Concrete
Table 9 summarizes the results of impact resistance test of fiber contcrete. It may be found that the
impact numbers at final cracking failure of glass fiber concrete is in the range of 213 to 408, in which
the fiber concrete with 1.0 % glass fiber resist the most number of blows of 408, subsequent by 1.5 %
fiber of 306 and 0.5 % fiber of 213 is the least. The result shows that the concrete containing 1.0 %
glass fiber presents the best impact resistance and the addition of glass fiber has evident effect on the
impact resistance of concrete. In addition, it is also found that the concrete containing 1.0 % steel
fiber resists the most number of blows of 271 and the concrete containing 1.5 % steel fiber exhibits
the least number of blows of 246.
Table 9: Impact resistance of fiber concrete (56 days)
Mix number Crack Number of Blows Mix number Crack Number of Blows
CF10 Initial 382
SF05 Initial 108
Final 382 Final 261
GF05 Initial 213
SF10 Initial 64
Final 213 Final 271
GF10 Initial 408
SF15 Initial 100
Final 408 Final 246
GF15 Initial 306
Final 306
Figure 13 illustrates the comparison of the impact resistance of three fiber concretes containing same
fiber amount of 1.0 %. From the figure it is found that the blow numbers at final-cracking of glass,
carbon and steel fiber concretes are 408, 382 and 271, respectively. It reveals that the glass fiber
concrete has the best impact resistance, subsequent by the carbon fiber concrete, and the steel fiber
concrete is the worst. In addition, it is also found that the carbon and glass fiber concretes have
equivalent blow numbers at initial-cracking and finial-cracking, while the steel fiber concrete exhibits
a difference of 210 blows. This result may be explained as that the three kinds of fibers appear
different reinforcing effects in concrete due to different conformations themselves. When an impact
load acts on the concrete, cracks may be occurred inside the specimen. But the fibers could prevent
immediately the cracks from developing further and the damage time of concrete could be also
delayed because of the effect of tensile force of fibers. Compare to the steel fiber, the carbon and
glass fibers are much smaller in size, more numbers of fibers will be distributed in concrete. This
could prevent effectively the microcracks from further developing. However, it also means that if the
microcracks break through the restrained forces of fibers, the microcracks will develop quickly and
lead to visible crack, such that the concrete is fractured.
The diameter of steel fiber is 16 to 35 times larger than those of carbon and glass fibers, every steel
fiber may confine greater volume of concrete. This provides a bigger space for the visible crack to
develop before the concrete fails (finial-cracking). Consequently, the steel fiber concrete may not be
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fractured by the occurrence of visible cracks but will be failed until the steel fiber is broken or pulled
out.
Figure 13: Comparison of impact resistance of fiber concrete
4. Conclusion
Based on the test results, the following conclusions can be drawn:
1. When the fiber content keeps 1.0 %, the steel fiber concrete exhibits better abrasion erosion
resistance in flow abrasion test than that of the carbon and glass fiber concretes.
2. It was found from the underwater abrasion test that the carbon and glass fiber concretes present
quite similar abrasion erosion resistance, while the steel fiber concrete exhibits the best abrasion
resistance, its average abrasion volume is 20 % lower than that of the other two fiber concretes.
3. When the fiber content keeps at 1.0 %, the glass fiber concrete has the best impact resistance,
subsequent by the carbon fiber concrete, and the steel fiber concrete is the worst.
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Taiwan Power Company Report. (in Chinese)
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of High-Strength Concrete,” a doctoral dissertation. (in Chinese)
0
100
200
300
400
500
CF10 GF10 SF10
Num
ber o
f Blo
ws
Initial CrackingFinal Cracking
343
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