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Abrasion resistance of high-strength concrete in hydraulic structures
Wear 259 (2005) 62–69
Abrasion resistance of high-strength concrete in hydraulic structures El˙zbieta Horszczaruk ∗ Technical University of Szczecin, al. Piast´ow 50, 70-311 Szczecin, Poland Received 29 July 2004; received in revised form 8 February 2005; accepted 8 February 2005 Available online 10 May 2005
Abstract This paper presents the results of the examinations of abrasive wear of the nine types of high-strength concrete (HSC) with compressive strength of 75 ÷ 120 MPa. The mixes were made with: Portland cement CEM I 42.5R, CEM I 52.5R and blast-furnace cement CEM IIIA 42.5, basalt aggregate with added superplasticizers and silica fume. The mixes contained of steel fiber: 30 and 50 mm length and aspect ratios of 60 and 50 and polypropylene fiber as a reinforcement. Two types of concrete were modified with latex. For the examinations of the abrasive resistance of HSC, the ASTM C 1138 (standard test method for abrasion resistance of concrete) method was selected. This paper contains the results of studies on the abrasive resistance of HSC in dependency of the compression strength, modulus of elasticity, fiber material and dimensions. The curves of wear of the examined concrete and the mean velocity of wear were determined. The obtained courses of wear were analyzed and compared with the results of examinations of standard concrete. © 2005 Elsevier B.V. All rights reserved. Keywords: Abrasion resistance; High-strength concrete; Kinetics of wear
1. Introduction The high-strength concrete (HSC) with high abrasion resistance are more frequently used for repairing of the hydrotechnic constructions damaged by the water mixed with rock waste such as stilling basins and overfalls. HSC are also used for new hydrotechnic constructions and concrete surfaces. The damages to the surface are caused by various phenomenons such as: abrasion, impact and cavitation. In case of hydrotechnic constructions, the determination of its durability is very important because of their high strategic and economic significance. There aren’t many publications examining the abrasive resistance of concrete from the modelling point of view. The abrasive resistance is most frequently described with B¨ohme’s disc [1]. This method uses a cubic sample (of a 71 mm side height) that is abraded on a steel disc, using type B80 corundum powder as an abrasive material. The abrasive wear is measured by the loss of height of the sample after 440 turns of the disc. This method is not ∗
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very useful in evaluation of abrasive erosion influenced concrete because it does not include the conditions of concrete wear. In case of HSC, the B¨ohme’s disc method provides the results of very little differentiation, therefore, we can’t compare the abrasion resistance of HSC of various composition and various strength. The American Standards ASTM presents six different methods of examination of abrasion resistance of concrete dependent of the abrasion mechanism. ASTM C 1138 [2] and ASTM C 779 [3] are highly recommended. But the main problem with these methods when examining the HSC is the examination period. The time of examination is 48 h—it is not long enough in case of HSC. The composition of HSC is often modified with various additives to obtain specific mechanical qualities that allow the use of that particular concrete in specific environmental conditions. For example, the use of the polypropylene fiber effects in limited solidifying contraction and the use of steel fiber increases the compression and tensile strength. This is the reason why the concept of HSC is replaced by the high performance concrete (HPC)—concrete with not only high strength but also with high durability in specific
El˙zbieta Horszczaruk / Wear 259 (2005) 62–69
Nomenclature b1 , b2 , b3 constant values DOW depth of wear (mm) E modulus of elasticity (GPa) fc compressive strength (MPa) m0 initial mass of the sample MDE grindability by micro-Deval method n number of samples R2 coefficient of determination t time of abrasion (h) VW velocity of wear (g/h, mg/h) VW (t) velocity of wear in time function W wear (g, %) W(t) wear in time function W/C water/cement ratio W/CM water/cementitious materials ratio Greek letters α material constant λ material constant m mass decrement after time t
environmental conditions. The abrasion resistance of concrete is mainly related to the compression strength, but not all concrete admixes used to improve its strength result in higher abrasion resistance. This paper presents the results of examinations of nine HSC modified with steel fiber, PVC fiber and latex. The examinations of an abrasion wear were conducted using two methods: the underwater method ASTM C 1138 with an abrasion time extended to 120 h and with the B¨ohme’s disc (DIN 52108).
2. The principal factors affecting the abrasion resistance of concrete The principal factors affecting the abrasion resistance of concrete can be the environmental conditions and dosage of aggregate, the concrete strength, the mixture proportioning, the use of special cement, the use of supplementary cementitious materials such as: fly ash, the addition of fiber. Two other important factors have an effect on abrasion resistance: surface finishing and the curing conditions. Compressive strength has been shown to be among the most important factors that influence the abrasion resistance of concrete. Gjø´ rv et al. [4] developed a testing machine to evaluate the wear resistance of concrete pavements subjected to circulating traffic action. In these experiments, four truck wheels with studded tires running at speeds of up to 70 km/h circulate over 12 massive concrete elements, each measuring 1.5 m in length. The authors have evaluated the influence of
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the nature of coarse aggregate and concrete moisture on the wear resistance of concrete. HSC with a 28-day compressive strength of 150 MPa made with hard Jasper coarse aggregate or diorite quartz showed the greatest resistance to wear damage. The use of concrete with compressive strength of 150 MPa is stipulated to double the service life of the pavement compared to concrete made with similar aggregate, but a compressive strength of 50 MPa. Holland et al. [5] established a dependency between compressive strength and underwater abrasion resistance at 72 h (ASTM C 1138, mass loss) of concrete used in the Los Angeles River basin. The tests showed that the underwater abrasion resistance increases with compressive strength. Holland studied the underwater abrasion resistance of concrete made with 11–15% silica fume and W/CM (water/cementitious materials ratio) varying between 0.24 and 0.34 for repair of Kinzua dam in Pennsylvania. Concretes had 28-day compressive strength up to 79 MPa. The use of silica fume improved the abrasion resistance compared to conventional concrete. Ghafoori et al. [6] studied the abrasion resistance of concrete pavement according to ASTM C 779, Procedure C, and examined the effect of matrix proportioning on the depth of wear damage. The water/cement ratio (W/C) of the tested mixtures varied between 0.21 and 0.34. The mixture proportioning ranged from 9:1 to 3:1 of aggregate to cement ratio. The compressive strength values at 28 days varied between 40 and 79 MPa. The abrasive resistance of concrete paving block was shown to depend strongly on the aggregate to cement ratio. The change in aggregate to cement ratio has much greater influence on abrasion resistance than changes in compressive or splitting tensile strength of concrete pavers. Naik et al. [7] determined the abrasion resistance of Class C fly ash concrete proportioned to have five levels of cement replacements (15, 30, 40, 50 and 70%). The W/CM was kept 0.35. The authors developed an accelerated test method to evaluate the wear resistance of HSC. Test results indicated that the abrasion resistance of concrete having up to 30% cement replacement with fly ash was comparable to the reference concrete at 28, 91 and 365 days. The results showed that compressive strength was important factor affecting abrasion resistance. Saucier et al. [8] determined the abrasion resistance of HPC from calcium aluminate cements. The studies on cement type influence on abrasive resistance of concrete in hydrotechnic constructions were also made by E. Horszczaruk [9]. McDonald [10] examined the cavitation resistance of over 80 various materials (with compression strength form 50 to 200 MPa) used for hydrotechnic construction repairs. A laboratory cavitation test apparatus was constructed by replacing a section of 305 mm diameter steel pipe with a Venturi-type test cell. An electric motor drives a centrifugal pomp at 1750 rpm, that draws water from a storage tank and produces a discharge velocity of approximately 35 m/sec through the Venturi tube. The surface area of the
450 22.5 – 45 0.27 2 630 16 1279 – 1.8 450 22.5 112.5 45 0.27 1.5 630 16 1279 70** – 450 135 – 45 0.27 1 630 16 1279 70** – 450 135 – 45 0.27 1 630 16 1279 70* – 470 135 – 47 0.26 1.5 1007 8 1006 70** – 470 135 – 47 0.26 1.5 1007 8 1006 70* – 470 135 – 47 0.26 1.5 1007 8 1006 – – Steel fibers ME30/50. Steel fibers ME50/1.00. ∗
470 135 – 47 0.26 2 1007 8 1006 – – Cement (kg/m3 ) Water (l/m3 ) Latex (l/m3 ) Silica fume (kg/m3 ) W/CM Superplasticizer (% mass of cement) Sand (kg/m3 ) Maximum diameter of basalt (mm) Basalt (kg/m3 ) Steel fibers (kg/m3 ) PVC fibers (kg/m3 )
∗∗
C9
Type of cement
Table 1 Mixture proportioning
4. Test procedures The abrasion–erosion resistance of concrete was evaluated according to ASTM C 1138, test method for abrasion resistance of concrete (underwater method). In this test, the concrete sample is subjected to an abrasive charge consisting of 70 chrome steel balls circulating in water over the concrete surface. A paddle rotating at 1200 rpm is used to cause the circulation of this abrasive charge. The mass loss and average
470 135 – 47 0.26 1 1007 8 1006 – –
CEM I 52.5R
C8 C7
CEM I 52.5R CEM I 52.5R
C6 C5
CEM III/A 42.5N
C1
CEM I 52.5R
Type of mix
C2
C3
C4
This paper presents the program of examination of nine HSC made of various cement type and modified with steel fiber, PVC fiber and latex. The concrete was made with three types of cement: Portland CEM I 42.5R and CEM I 52.5R and metallurgic CEM IIIA 42.5 (according to the EN 197-1 standard). All the mixes contained fly ash (SiO2 , 93%) and silica fume (10% of cement mass). Mixes contained the fractionated basalt aggregate with specific gravity of 3.03 kg/m3 and maximal graining of 8 and 16 mm. The grindability of the aggregate measured with Los Angeles method was 21.5% and with micro-Deval method, MDE = 6.5. Five mixes C4–C8 were made using steel fiber ME Fasersysteme type ME 30/50 and ME 50/1.00. The C8 mix contained also the latex additive (40% water solution)—25% of cement mass. The C9 mix was made using the 19 mm PVC fiber. All these mixes contained superplasticizer – 1 ÷ 2% of cement mass – to obtain semi-liquid or plastic mixture. The mixture proportions are shown in Table 1.
CEM III/A 42.5N
3. Materials and mixture composition
CEM III/A 42.5N
test sample exposed to the high-velocity flow and cavitation is approximately 150 cm2 . In general, the cementitiousbased materials exhibited poor cavitation resistance. While the cavitation resistance of conventional concrete with addition of latex, silica fume, reactive powder and fiber reinforcement was improved, volume losses for most of these materials were significantly higher than of the polymer-based materials. Sonebi and Khayat [11] studied the abrasion resistance of 13 HSC mixtures made with different aggregate types and special materials, such as steel fibers and latex incorporated to enhance mechanical performance. The concrete was tested according to ASTM C 779, Procedure C and ASTM C 1138. The recommended test duration of 20 min and 72 h for the ASTM C 779 and ASTM C 1138—underwater method test, respectively, are sufficient to differentiate between the levels of wear damage of HSC. Good correlations exist between the wear damage measured at 72 h and those determined at 48, 96 and 120 h for the underwater test and 10 and 20 min results for mechanical abrasion test. The incorporation of latex and steel fiber did not improve significantly the mechanical and hydraulic abrasion resistance of such HSC.
CEM I 52.5R
El˙zbieta Horszczaruk / Wear 259 (2005) 62–69
CEM I 42.5R
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El˙zbieta Horszczaruk / Wear 259 (2005) 62–69
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Table 2 Mass loss and depth of abrasion (ASTM C 1138) Mix time (h)
C1
C2
C3
C4
C5
C6
C7
C8
C9
0.50 0.93 1.36 1.79 2.22 2.55 3.48 4.24
0.72 1.68 2.55. 3.32 3.33 4.59 5.83 7.05
1.09 2.04 2.77 3.35 3.99 4.52 5.55 6.57
0.65 1.16 1.68 2.18 2.61 2.99 4.06 4.90
0.24 0.48 0.70 0.95 1.17 1.36 1.73 2.11
0.24 0.52 0.85 1.13 1.56 1.67 2.06 2.54
0.57 0.90 1.17 1.36 1.61 1.85 2.12 2.59
0.13 0.31 0.56 0.77 1.00 1.23 1.63 2.09
Depth of damage (mm) 12 0.26 0.50 24 0.87 0.93 36 1.20 1.36 48 1.68 1.79 60 2.10 2.22 72 2.46 2.55 96 3.40 3.48 120 3.96 4.25
1.13 2.31 3.48 4.59 5.30 6.16 7.73 9.21
1.48 2.71 3.72 4.46 5.23 5.84 7.18 8.48
1.08 1.89 3.05 4.07 4.76 5.15 6.59 7.92
0.28 0.65 0.94 1.30 1.65 1.86 2.29 2.89
0.38 0.78 1.14 1.53 1.92 2.22 2.73 3.27
1.00 1.45 1.88 2.08 2.42 2.91 3.17 3.61
0.15 0.37 0.71 0.95 1.25 1.55 2.01 2.71
Mass loss (%) 12 0.19 24 0.50 36 0.87 48 1.27 60 1.67 72 1.94 96 2.42 120 3.09
Fig. 1. The results of abrasive resistance examinations with underwater method and B¨ohme’s disc.
5.1. Difference between underwater method and abrasion test on B¨ohme disc depth of the abrasion–erosion are measured at 12-h intervals for 72 h. The test duration was increased to 120 h in some cases to investigate the need of prolonging the testing time to better differentiate between various levels of wear damage of HSC. Three cylindrical samples measuring 100 mm in height and 300 mm in diameter were cast and used to evaluate the underwater abrasion resistance for each concrete. The samples were demoulded after 1 day and stored in water at 20 ± 3 ◦ C. After 28 days, the abrasion resistance was tested for the topfinished surfaces. Several 150 mm in diameter and 300 mm in height concrete cylinders were sampled for compressive strength and modulus of elasticity. They were demoulded 1 day after casting and cured in water for 28 days. The mechanical abrasion resistance of concrete was evaluated according to B¨ohme disc.
Fig. 1 shows the comparison of the abrasion resistance test results of nine HSC using two methods: underwater method (120 h period) and the B¨ohme’s disc. The second one provided the grindability of 1.5–1.8 mm—similar for all the concrete mixes, and therefore, it was useless for the abrasion resistance evaluation. The underwater method (ASTM C 1138) simulates the natural conditions of abrasive concrete wear and can be used in case of HSC for comparative analysis of abrasive resistance of standard and high-strength concrete. However, in case of HSC, it requires longer examination period – up to 96 h – to show mass decrement that allows presentation of distinct differences between the samples. The examination period issue and the mass decrement estimation in underwater method are presented in paragraph 5.5. 5.2. The influence of fiber on the abrasive resistance of HSC
5. Test results and discussion Table 2 summarizes the results of underwater abrasion test. The reported strength and depth of wear damage results are mean values of three tests. Table 3 presents the results of mechanical abrasion test on B¨ohme disc for the nine tested mixtures with the results of compressive strength and modulus of elasticity after 28 days.
Figs. 2 and 3 show the results of the examinations of abrasive wear of three HSC made of blast-furnace cement (W/CM = 0.26). The C3 concrete was made without the fiber, the C4 and C5 concrete contains 70 kg/m3 steel fiber ME 30/50 and ME 50/1.00. The underwater method was used for the abrasive resistance examinations and it shows the percentage mass decrement (Fig. 2) and mean depth of wear (Fig. 3).
Table 3 Mean depth of mechanical wear by B¨ohme disc and mechanical properties of hardened concrete Type of concrete
C1
C2
C3
C4
C5
C6
C7
C8
C9
Abrasive wear by B¨ohme disc (mm) Compressive strength fc (MPa) Modulus of elasticity E (GPa)
1.6 95.83 56.12
1.6 89.75 56.70
1.5 74.18 47.60
1.5 76.40 53.98
1.5 91.59 56.80
1.6 91.81 57.92
1.6 115.82 73.20
1.8 91.44 63.36
1.6 98.23 59.00
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Fig. 2. Mass decrement of the samples in the underwater method.
Fig. 5. Mass loss for HSC made with different fibers.
19 mm Fibermesch fiber had the highest abrasive resistance. This fiber is added to eliminate the autogenic contraction and to increase the tensile and bending strength. The latex emulsion admix used to increase the chemical resistance of concrete had practically no influence on the abrasive resistance. During the initial stage of abrasion, the abrasive wear of concrete with latex is even higher than for the concrete without any additives. It happens because of the layer of the latex without of the aggregate is generated on their surface—this layer has much lower strength than the samples’ core. The latex admix alone causes lower 28-day compression strength.
Fig. 3. Mean depth of wear of the samples in the underwater method.
5.3. Correlations between the depth of wear damage and compressive strength
In both cases, the C5 concrete (with the fiber ME 50/1.00) shows the highest abrasive resistance. It is 30% higher than the resistance of the non-reinforced concrete. It can be explained by the fact that the 28-day compression strength of the C5 concrete is 25% higher than the strength of the other two concretes. In case of C4, concrete the differences in abrasive resistance were minimal compared to the non-reinforced concrete C3. The comparison of abrasive resistance of HSC reinforced with fiber and with latex additive is shown in Figs. 4 and 5. All the samples were made with cement CEM I 52.5 R of W/CM ratio of 0.27. The results were compared to the results of C1 (non-reinforced) concrete. The concrete reinforced with
Fig. 6 shows the relations between the depth of wear damage caused by abrasion (HSC examined after 48, 72 and 128 h) and 28-day compressive strength. Presented samples showed 28-day compression strength of over 70 MPa. All the dependencies are for abrasive resistance of the top surface of that samples examined with underwater method. The following equation is produced from these dependencies:
Fig. 4. Depth of underwater abrasion damage for HSC made with different fibers.
Fig. 6. Relationship between 28-day compressive strength and depth of wear of top surface at 48, 72 and 120 h, underwater method.
DOW = b1 + b2 fc + b3 fc2
(1)
El˙zbieta Horszczaruk / Wear 259 (2005) 62–69
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Fig. 8. The abrasive wear of standard concrete (B30) made of natural aggregate of various grain-size distribution (4 ÷ 16 mm). W, wear; VW , velocity of wear; t, time.
Fig. 7. Abrasive wear of the examined HSC.
where DOW is the depth of wear (mm) and fc is the compressive strength (MPa). The coefficient R2 for the dependency of depth of abrasive wear for all abrasion periods was 0.96. All the above values were determined for n = 3 samples. In the abrasion resistance range over 90 MPa, all the graphs of the depth of wear DOW are parallel—it means that the velocity of wear was constant in time. The correlation obtained here allows to shorten the examination period to 48 h even with lowering the coefficient R2 for higher number of samples n for the specified strength fc and to estimate the mass of loss of the samples after 120 h of abrasion. The obtained dependency has the same pattern as the one obtained by Sonebi [11] for HSC examined with mechanical method ASTM C 779.
6. The analysis of velocity of HSC wear under the abrasive erosion Fig. 7 shows the results of the examinations for C1–C9 concrete. The concrete wear W caused by the abrasive erosion is presented as the changes of the loss of mass of the concrete in time: W = m = f(t). The velocity of wear VW (g/h) is presented as the relation of the loss of mass of the sample to the time in which this loss had occurred. The curves of velocity of the loss of mass are shown on Fig. 7. After analyzing these runs of wear of HSC, we can confirm their difference from the runs for standard concrete. The abrasive wear for the standard concrete (B30) made of natural aggregate of various grain-size distribution is shown in Fig. 8. The analysis of wear of standard concrete under the abrasive erosion allows us to determine three basic periods: the accumulation period (fast wear increase in a short time, around 2 h), fading period (the wear increase is very small) and the stabilization period (the velocity of wear VW is constant). In
case of the abrasive wear, there is no visible incubation period that is very characteristic for the cavitation wear. In case of standard concrete, the abrasive wear stabilized after 48 h of the test. The results of this test and the description of the model of the kinetics of abrasive wear of standard concrete are presented in references [12] and [13]. As for the HSC, the course of the velocity of wear has a different characteristic (Fig. 7). The accumulation period lasted 12–24 h and was much longer than for the standard concrete (2 h). Analyzing the course of abrasive wear of concrete, we can describe two phases: phase I, the wear of the surface (made mainly of cement paste and fine aggregate) and phase II, with constant velocity of wear (because of highest homogeneity of the samples’ core). In case of concrete construction with or without the reinforcement, we cannot clearly isolate the destruction phase. In real environment, there are other corrosion actions besides the abrasive erosion that can mutually amplify itself. The destruction phase is individually defined based on its maximal bearing capacity and individual environmental conditions. Assuming in our general model of abrasive wear of non-reinforced concrete that the environmental conditions are constant and we only take into consideration the concrete wear from abrasion, we can describe the main differences in the course of phase I and phase II for the standard and high-strength concrete. For the standard concrete, the course of wear (Fig. 8) is presented by the following equation: α m λ W(t) = (2) = 1− m0 λ+t where m is the mass decrement after time t, m0 is the initial mass of the sample, α and λ are the material constants determined in experiment and t is the time of abrasion. Reference [12] presents the procedure of determining the α and λ. The time of phase I according to the course of velocity
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El˙zbieta Horszczaruk / Wear 259 (2005) 62–69
Table 4 Relations between underwater abrasion resistance of HSC Concrete
Correlation W = b1 tb2
C1 C2 C3* C4 C5 C6 C7 C8 C9 ∗
W = bt
b1
b2
R2
0.0105 0.0487 0.0720 0.1710 0.0722 0.0236 0.0198 0.1143 0.0068
1.2116 0.9314 0.9772 0.7667 0.8783 0.9461 1.0327 0.6466 1.2105
0.989 0.999 0.991 0.997 0.999 0.999 0.990 0.998 0.997
b
R2
0.259 0.036 0.062 0.062 0.042 0.018 0.023 0.024 0.017
0.991 0.997 0.984 0.984 0.991 0.994 0.986 0.906 0.994
Max R2 = 0.999 for correlation W = b1 + b2 t + b3 t2 .
of wear is around 6 h. During the initial 2 h, a quick increase of velocity VW (accumulation period) was observed. Then comes a very fast decrease of velocity of wear (fading period) that lasts around 4 h. After about 6 h, the wear process stabilizes and then the phase II begins—stable wear of the material. For the examined HSC, the course of wear W(t) can be approximated with the power function, but when we assume the linear course of wear W(t), the obtained values of coefficient R2 are only minimally different (Table 4). Analyzing the run of velocity of wear VW (Fig. 9), we can observe that the velocity increase ends in 12–24 h. In case of concrete with compression strength over 80 MPa (C1, C2), there is no distinct decrease of velocity, only a small one, then the velocity of wear stabilizes. This linear course of wear W(t) starts after 24 h for B1 and B2 concrete and for all other ones between 36 and 60 h. After this period, phase II starts—stable wear of material. If we omit the initial stage of wear (phase I) and assume the linear wear W(t)—the velocity of wear VW will be constant (Fig. 10). All the modelling assumptions need to be verified experimentally. The proposed model of abrasive wear of HSC can be used for preliminary estimation of abrasive wear in hydrotechnic constructions.
Fig. 10. The model of HSC wear without the phase I: W, wear; VW , velocity of wear; t, time.
7. Conclusions From the test results, the following conclusions were formulated: 1. The ASTM C 1138 method is suitable for determination of the abrasion resistance of HSC with a 28-day compressive strength of 80–120 MPa. 2. The examination period of the underwater method for the HSC should be at least 72 h. 3. The assumption of linear dependency of HSC wear is correct, if we omit the initial stage of abrasion—12–24 h for the HSC is omited. The velocity of wear can be assumed constant. All the above assumptions are valid for nonreinforced HSC with compression strength over 80 MPa. 4. The latex additive does not improve the abrasion resistance of concrete. The HSC with added PVC fiber showed improvement in this area.
Acknowledgement The research has been supported by science project of the Minister of Scientific Research and Information Technology State No. 5 T07E 01924.
References
Fig. 9. Velocity of HSC wear. VW , velocity of wear; t, time.
[1] DIN 52108:202-07, Testing of inorganic non-metallic materials – Wear test using the grinding wheel according to B¨ohme – Grinding wheel method. [2] ASTM C 1138-97, Standard test method for abrasion resistance of concrete (underwater method), in: Annual Book of ASTM Standards, vol. 04.02, ASTM, West Conshohocken, 2002. [3] ASTM C 779/C 779M – 00, Standard test method for abrasion resistance of horizontal concrete surfaces, in: Annual Book of ASTM Standards, vol. 04.02, ASTM, West Conshohocken, 2002. [4] O.E. Gjø´ rv, Abrasion resistance of high-strength concrete pavements, ACI Mater. J. 6 (1990) 45–48. [5] T.C. Holland, Erosion resistance with silica-fume concrete, ACI Concr. Int. 3 (1987) 32–40.
El˙zbieta Horszczaruk / Wear 259 (2005) 62–69 [6] N. Ghafoori, B.M. Surandar, Abrasion resistance of concrete block pavements, ACI Mater. J. 1 (1995) 25–36. [7] T.R. Naik, Abrasion resistance of high-strength concrete made with class C fly ash, ACI Mater. J. 6 (1995) 649–659. [8] F. Saucier, Calcium aluminates cement based concretes for hydraulic structures: resistance to erosion, abrasion & cavitation, in: N. Banthia (Ed.), Proceedings of the Third International Conference on Concrete Under Severe Conditions, The University of British Columbia, Vancouver, 2001, pp. 1562–1569. [9] E. Horszczaruk, Abrasive wear of concrete in hydraulic structures, Tribologia 3 (2003) 19–36.
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[10] J.E. McDonald, Evaluation of materials for repair of erosion damage in hydraulic structures, in: Durability of Concrete, Fifth International conference, Barcelona, ACI, SP-192-54, 2000, pp. 887– 898. [11] M. Sonebi, K.H. Khayat, Testing abrasion resistance of high-strength concrete. cement, Concr. Aggregates 23 (2001) 34–43. [12] E. Horszczaruk, The model of abrasive wear of concrete in hydraulic structures, Wear 256 (2004) 787–796. [13] E. Horszczaruk, Wear kinetics of ordinary concrete submit to abrasive erosion, Ochrona przed Korozja 5s/A (2004) 119– 126.
Abrasion resistance of high-strength concrete in hydraulic structures El˙zbieta Horszczaruk ∗ Technical University of Szczecin, al. Piast´ow 50, 70-311 Szczecin, Poland Received 29 July 2004; received in revised form 8 February 2005; accepted 8 February 2005 Available online 10 May 2005
Abstract This paper presents the results of the examinations of abrasive wear of the nine types of high-strength concrete (HSC) with compressive strength of 75 ÷ 120 MPa. The mixes were made with: Portland cement CEM I 42.5R, CEM I 52.5R and blast-furnace cement CEM IIIA 42.5, basalt aggregate with added superplasticizers and silica fume. The mixes contained of steel fiber: 30 and 50 mm length and aspect ratios of 60 and 50 and polypropylene fiber as a reinforcement. Two types of concrete were modified with latex. For the examinations of the abrasive resistance of HSC, the ASTM C 1138 (standard test method for abrasion resistance of concrete) method was selected. This paper contains the results of studies on the abrasive resistance of HSC in dependency of the compression strength, modulus of elasticity, fiber material and dimensions. The curves of wear of the examined concrete and the mean velocity of wear were determined. The obtained courses of wear were analyzed and compared with the results of examinations of standard concrete. © 2005 Elsevier B.V. All rights reserved. Keywords: Abrasion resistance; High-strength concrete; Kinetics of wear
1. Introduction The high-strength concrete (HSC) with high abrasion resistance are more frequently used for repairing of the hydrotechnic constructions damaged by the water mixed with rock waste such as stilling basins and overfalls. HSC are also used for new hydrotechnic constructions and concrete surfaces. The damages to the surface are caused by various phenomenons such as: abrasion, impact and cavitation. In case of hydrotechnic constructions, the determination of its durability is very important because of their high strategic and economic significance. There aren’t many publications examining the abrasive resistance of concrete from the modelling point of view. The abrasive resistance is most frequently described with B¨ohme’s disc [1]. This method uses a cubic sample (of a 71 mm side height) that is abraded on a steel disc, using type B80 corundum powder as an abrasive material. The abrasive wear is measured by the loss of height of the sample after 440 turns of the disc. This method is not ∗
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very useful in evaluation of abrasive erosion influenced concrete because it does not include the conditions of concrete wear. In case of HSC, the B¨ohme’s disc method provides the results of very little differentiation, therefore, we can’t compare the abrasion resistance of HSC of various composition and various strength. The American Standards ASTM presents six different methods of examination of abrasion resistance of concrete dependent of the abrasion mechanism. ASTM C 1138 [2] and ASTM C 779 [3] are highly recommended. But the main problem with these methods when examining the HSC is the examination period. The time of examination is 48 h—it is not long enough in case of HSC. The composition of HSC is often modified with various additives to obtain specific mechanical qualities that allow the use of that particular concrete in specific environmental conditions. For example, the use of the polypropylene fiber effects in limited solidifying contraction and the use of steel fiber increases the compression and tensile strength. This is the reason why the concept of HSC is replaced by the high performance concrete (HPC)—concrete with not only high strength but also with high durability in specific
El˙zbieta Horszczaruk / Wear 259 (2005) 62–69
Nomenclature b1 , b2 , b3 constant values DOW depth of wear (mm) E modulus of elasticity (GPa) fc compressive strength (MPa) m0 initial mass of the sample MDE grindability by micro-Deval method n number of samples R2 coefficient of determination t time of abrasion (h) VW velocity of wear (g/h, mg/h) VW (t) velocity of wear in time function W wear (g, %) W(t) wear in time function W/C water/cement ratio W/CM water/cementitious materials ratio Greek letters α material constant λ material constant m mass decrement after time t
environmental conditions. The abrasion resistance of concrete is mainly related to the compression strength, but not all concrete admixes used to improve its strength result in higher abrasion resistance. This paper presents the results of examinations of nine HSC modified with steel fiber, PVC fiber and latex. The examinations of an abrasion wear were conducted using two methods: the underwater method ASTM C 1138 with an abrasion time extended to 120 h and with the B¨ohme’s disc (DIN 52108).
2. The principal factors affecting the abrasion resistance of concrete The principal factors affecting the abrasion resistance of concrete can be the environmental conditions and dosage of aggregate, the concrete strength, the mixture proportioning, the use of special cement, the use of supplementary cementitious materials such as: fly ash, the addition of fiber. Two other important factors have an effect on abrasion resistance: surface finishing and the curing conditions. Compressive strength has been shown to be among the most important factors that influence the abrasion resistance of concrete. Gjø´ rv et al. [4] developed a testing machine to evaluate the wear resistance of concrete pavements subjected to circulating traffic action. In these experiments, four truck wheels with studded tires running at speeds of up to 70 km/h circulate over 12 massive concrete elements, each measuring 1.5 m in length. The authors have evaluated the influence of
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the nature of coarse aggregate and concrete moisture on the wear resistance of concrete. HSC with a 28-day compressive strength of 150 MPa made with hard Jasper coarse aggregate or diorite quartz showed the greatest resistance to wear damage. The use of concrete with compressive strength of 150 MPa is stipulated to double the service life of the pavement compared to concrete made with similar aggregate, but a compressive strength of 50 MPa. Holland et al. [5] established a dependency between compressive strength and underwater abrasion resistance at 72 h (ASTM C 1138, mass loss) of concrete used in the Los Angeles River basin. The tests showed that the underwater abrasion resistance increases with compressive strength. Holland studied the underwater abrasion resistance of concrete made with 11–15% silica fume and W/CM (water/cementitious materials ratio) varying between 0.24 and 0.34 for repair of Kinzua dam in Pennsylvania. Concretes had 28-day compressive strength up to 79 MPa. The use of silica fume improved the abrasion resistance compared to conventional concrete. Ghafoori et al. [6] studied the abrasion resistance of concrete pavement according to ASTM C 779, Procedure C, and examined the effect of matrix proportioning on the depth of wear damage. The water/cement ratio (W/C) of the tested mixtures varied between 0.21 and 0.34. The mixture proportioning ranged from 9:1 to 3:1 of aggregate to cement ratio. The compressive strength values at 28 days varied between 40 and 79 MPa. The abrasive resistance of concrete paving block was shown to depend strongly on the aggregate to cement ratio. The change in aggregate to cement ratio has much greater influence on abrasion resistance than changes in compressive or splitting tensile strength of concrete pavers. Naik et al. [7] determined the abrasion resistance of Class C fly ash concrete proportioned to have five levels of cement replacements (15, 30, 40, 50 and 70%). The W/CM was kept 0.35. The authors developed an accelerated test method to evaluate the wear resistance of HSC. Test results indicated that the abrasion resistance of concrete having up to 30% cement replacement with fly ash was comparable to the reference concrete at 28, 91 and 365 days. The results showed that compressive strength was important factor affecting abrasion resistance. Saucier et al. [8] determined the abrasion resistance of HPC from calcium aluminate cements. The studies on cement type influence on abrasive resistance of concrete in hydrotechnic constructions were also made by E. Horszczaruk [9]. McDonald [10] examined the cavitation resistance of over 80 various materials (with compression strength form 50 to 200 MPa) used for hydrotechnic construction repairs. A laboratory cavitation test apparatus was constructed by replacing a section of 305 mm diameter steel pipe with a Venturi-type test cell. An electric motor drives a centrifugal pomp at 1750 rpm, that draws water from a storage tank and produces a discharge velocity of approximately 35 m/sec through the Venturi tube. The surface area of the
450 22.5 – 45 0.27 2 630 16 1279 – 1.8 450 22.5 112.5 45 0.27 1.5 630 16 1279 70** – 450 135 – 45 0.27 1 630 16 1279 70** – 450 135 – 45 0.27 1 630 16 1279 70* – 470 135 – 47 0.26 1.5 1007 8 1006 70** – 470 135 – 47 0.26 1.5 1007 8 1006 70* – 470 135 – 47 0.26 1.5 1007 8 1006 – – Steel fibers ME30/50. Steel fibers ME50/1.00. ∗
470 135 – 47 0.26 2 1007 8 1006 – – Cement (kg/m3 ) Water (l/m3 ) Latex (l/m3 ) Silica fume (kg/m3 ) W/CM Superplasticizer (% mass of cement) Sand (kg/m3 ) Maximum diameter of basalt (mm) Basalt (kg/m3 ) Steel fibers (kg/m3 ) PVC fibers (kg/m3 )
∗∗
C9
Type of cement
Table 1 Mixture proportioning
4. Test procedures The abrasion–erosion resistance of concrete was evaluated according to ASTM C 1138, test method for abrasion resistance of concrete (underwater method). In this test, the concrete sample is subjected to an abrasive charge consisting of 70 chrome steel balls circulating in water over the concrete surface. A paddle rotating at 1200 rpm is used to cause the circulation of this abrasive charge. The mass loss and average
470 135 – 47 0.26 1 1007 8 1006 – –
CEM I 52.5R
C8 C7
CEM I 52.5R CEM I 52.5R
C6 C5
CEM III/A 42.5N
C1
CEM I 52.5R
Type of mix
C2
C3
C4
This paper presents the program of examination of nine HSC made of various cement type and modified with steel fiber, PVC fiber and latex. The concrete was made with three types of cement: Portland CEM I 42.5R and CEM I 52.5R and metallurgic CEM IIIA 42.5 (according to the EN 197-1 standard). All the mixes contained fly ash (SiO2 , 93%) and silica fume (10% of cement mass). Mixes contained the fractionated basalt aggregate with specific gravity of 3.03 kg/m3 and maximal graining of 8 and 16 mm. The grindability of the aggregate measured with Los Angeles method was 21.5% and with micro-Deval method, MDE = 6.5. Five mixes C4–C8 were made using steel fiber ME Fasersysteme type ME 30/50 and ME 50/1.00. The C8 mix contained also the latex additive (40% water solution)—25% of cement mass. The C9 mix was made using the 19 mm PVC fiber. All these mixes contained superplasticizer – 1 ÷ 2% of cement mass – to obtain semi-liquid or plastic mixture. The mixture proportions are shown in Table 1.
CEM III/A 42.5N
3. Materials and mixture composition
CEM III/A 42.5N
test sample exposed to the high-velocity flow and cavitation is approximately 150 cm2 . In general, the cementitiousbased materials exhibited poor cavitation resistance. While the cavitation resistance of conventional concrete with addition of latex, silica fume, reactive powder and fiber reinforcement was improved, volume losses for most of these materials were significantly higher than of the polymer-based materials. Sonebi and Khayat [11] studied the abrasion resistance of 13 HSC mixtures made with different aggregate types and special materials, such as steel fibers and latex incorporated to enhance mechanical performance. The concrete was tested according to ASTM C 779, Procedure C and ASTM C 1138. The recommended test duration of 20 min and 72 h for the ASTM C 779 and ASTM C 1138—underwater method test, respectively, are sufficient to differentiate between the levels of wear damage of HSC. Good correlations exist between the wear damage measured at 72 h and those determined at 48, 96 and 120 h for the underwater test and 10 and 20 min results for mechanical abrasion test. The incorporation of latex and steel fiber did not improve significantly the mechanical and hydraulic abrasion resistance of such HSC.
CEM I 52.5R
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CEM I 42.5R
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Table 2 Mass loss and depth of abrasion (ASTM C 1138) Mix time (h)
C1
C2
C3
C4
C5
C6
C7
C8
C9
0.50 0.93 1.36 1.79 2.22 2.55 3.48 4.24
0.72 1.68 2.55. 3.32 3.33 4.59 5.83 7.05
1.09 2.04 2.77 3.35 3.99 4.52 5.55 6.57
0.65 1.16 1.68 2.18 2.61 2.99 4.06 4.90
0.24 0.48 0.70 0.95 1.17 1.36 1.73 2.11
0.24 0.52 0.85 1.13 1.56 1.67 2.06 2.54
0.57 0.90 1.17 1.36 1.61 1.85 2.12 2.59
0.13 0.31 0.56 0.77 1.00 1.23 1.63 2.09
Depth of damage (mm) 12 0.26 0.50 24 0.87 0.93 36 1.20 1.36 48 1.68 1.79 60 2.10 2.22 72 2.46 2.55 96 3.40 3.48 120 3.96 4.25
1.13 2.31 3.48 4.59 5.30 6.16 7.73 9.21
1.48 2.71 3.72 4.46 5.23 5.84 7.18 8.48
1.08 1.89 3.05 4.07 4.76 5.15 6.59 7.92
0.28 0.65 0.94 1.30 1.65 1.86 2.29 2.89
0.38 0.78 1.14 1.53 1.92 2.22 2.73 3.27
1.00 1.45 1.88 2.08 2.42 2.91 3.17 3.61
0.15 0.37 0.71 0.95 1.25 1.55 2.01 2.71
Mass loss (%) 12 0.19 24 0.50 36 0.87 48 1.27 60 1.67 72 1.94 96 2.42 120 3.09
Fig. 1. The results of abrasive resistance examinations with underwater method and B¨ohme’s disc.
5.1. Difference between underwater method and abrasion test on B¨ohme disc depth of the abrasion–erosion are measured at 12-h intervals for 72 h. The test duration was increased to 120 h in some cases to investigate the need of prolonging the testing time to better differentiate between various levels of wear damage of HSC. Three cylindrical samples measuring 100 mm in height and 300 mm in diameter were cast and used to evaluate the underwater abrasion resistance for each concrete. The samples were demoulded after 1 day and stored in water at 20 ± 3 ◦ C. After 28 days, the abrasion resistance was tested for the topfinished surfaces. Several 150 mm in diameter and 300 mm in height concrete cylinders were sampled for compressive strength and modulus of elasticity. They were demoulded 1 day after casting and cured in water for 28 days. The mechanical abrasion resistance of concrete was evaluated according to B¨ohme disc.
Fig. 1 shows the comparison of the abrasion resistance test results of nine HSC using two methods: underwater method (120 h period) and the B¨ohme’s disc. The second one provided the grindability of 1.5–1.8 mm—similar for all the concrete mixes, and therefore, it was useless for the abrasion resistance evaluation. The underwater method (ASTM C 1138) simulates the natural conditions of abrasive concrete wear and can be used in case of HSC for comparative analysis of abrasive resistance of standard and high-strength concrete. However, in case of HSC, it requires longer examination period – up to 96 h – to show mass decrement that allows presentation of distinct differences between the samples. The examination period issue and the mass decrement estimation in underwater method are presented in paragraph 5.5. 5.2. The influence of fiber on the abrasive resistance of HSC
5. Test results and discussion Table 2 summarizes the results of underwater abrasion test. The reported strength and depth of wear damage results are mean values of three tests. Table 3 presents the results of mechanical abrasion test on B¨ohme disc for the nine tested mixtures with the results of compressive strength and modulus of elasticity after 28 days.
Figs. 2 and 3 show the results of the examinations of abrasive wear of three HSC made of blast-furnace cement (W/CM = 0.26). The C3 concrete was made without the fiber, the C4 and C5 concrete contains 70 kg/m3 steel fiber ME 30/50 and ME 50/1.00. The underwater method was used for the abrasive resistance examinations and it shows the percentage mass decrement (Fig. 2) and mean depth of wear (Fig. 3).
Table 3 Mean depth of mechanical wear by B¨ohme disc and mechanical properties of hardened concrete Type of concrete
C1
C2
C3
C4
C5
C6
C7
C8
C9
Abrasive wear by B¨ohme disc (mm) Compressive strength fc (MPa) Modulus of elasticity E (GPa)
1.6 95.83 56.12
1.6 89.75 56.70
1.5 74.18 47.60
1.5 76.40 53.98
1.5 91.59 56.80
1.6 91.81 57.92
1.6 115.82 73.20
1.8 91.44 63.36
1.6 98.23 59.00
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Fig. 2. Mass decrement of the samples in the underwater method.
Fig. 5. Mass loss for HSC made with different fibers.
19 mm Fibermesch fiber had the highest abrasive resistance. This fiber is added to eliminate the autogenic contraction and to increase the tensile and bending strength. The latex emulsion admix used to increase the chemical resistance of concrete had practically no influence on the abrasive resistance. During the initial stage of abrasion, the abrasive wear of concrete with latex is even higher than for the concrete without any additives. It happens because of the layer of the latex without of the aggregate is generated on their surface—this layer has much lower strength than the samples’ core. The latex admix alone causes lower 28-day compression strength.
Fig. 3. Mean depth of wear of the samples in the underwater method.
5.3. Correlations between the depth of wear damage and compressive strength
In both cases, the C5 concrete (with the fiber ME 50/1.00) shows the highest abrasive resistance. It is 30% higher than the resistance of the non-reinforced concrete. It can be explained by the fact that the 28-day compression strength of the C5 concrete is 25% higher than the strength of the other two concretes. In case of C4, concrete the differences in abrasive resistance were minimal compared to the non-reinforced concrete C3. The comparison of abrasive resistance of HSC reinforced with fiber and with latex additive is shown in Figs. 4 and 5. All the samples were made with cement CEM I 52.5 R of W/CM ratio of 0.27. The results were compared to the results of C1 (non-reinforced) concrete. The concrete reinforced with
Fig. 6 shows the relations between the depth of wear damage caused by abrasion (HSC examined after 48, 72 and 128 h) and 28-day compressive strength. Presented samples showed 28-day compression strength of over 70 MPa. All the dependencies are for abrasive resistance of the top surface of that samples examined with underwater method. The following equation is produced from these dependencies:
Fig. 4. Depth of underwater abrasion damage for HSC made with different fibers.
Fig. 6. Relationship between 28-day compressive strength and depth of wear of top surface at 48, 72 and 120 h, underwater method.
DOW = b1 + b2 fc + b3 fc2
(1)
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Fig. 8. The abrasive wear of standard concrete (B30) made of natural aggregate of various grain-size distribution (4 ÷ 16 mm). W, wear; VW , velocity of wear; t, time.
Fig. 7. Abrasive wear of the examined HSC.
where DOW is the depth of wear (mm) and fc is the compressive strength (MPa). The coefficient R2 for the dependency of depth of abrasive wear for all abrasion periods was 0.96. All the above values were determined for n = 3 samples. In the abrasion resistance range over 90 MPa, all the graphs of the depth of wear DOW are parallel—it means that the velocity of wear was constant in time. The correlation obtained here allows to shorten the examination period to 48 h even with lowering the coefficient R2 for higher number of samples n for the specified strength fc and to estimate the mass of loss of the samples after 120 h of abrasion. The obtained dependency has the same pattern as the one obtained by Sonebi [11] for HSC examined with mechanical method ASTM C 779.
6. The analysis of velocity of HSC wear under the abrasive erosion Fig. 7 shows the results of the examinations for C1–C9 concrete. The concrete wear W caused by the abrasive erosion is presented as the changes of the loss of mass of the concrete in time: W = m = f(t). The velocity of wear VW (g/h) is presented as the relation of the loss of mass of the sample to the time in which this loss had occurred. The curves of velocity of the loss of mass are shown on Fig. 7. After analyzing these runs of wear of HSC, we can confirm their difference from the runs for standard concrete. The abrasive wear for the standard concrete (B30) made of natural aggregate of various grain-size distribution is shown in Fig. 8. The analysis of wear of standard concrete under the abrasive erosion allows us to determine three basic periods: the accumulation period (fast wear increase in a short time, around 2 h), fading period (the wear increase is very small) and the stabilization period (the velocity of wear VW is constant). In
case of the abrasive wear, there is no visible incubation period that is very characteristic for the cavitation wear. In case of standard concrete, the abrasive wear stabilized after 48 h of the test. The results of this test and the description of the model of the kinetics of abrasive wear of standard concrete are presented in references [12] and [13]. As for the HSC, the course of the velocity of wear has a different characteristic (Fig. 7). The accumulation period lasted 12–24 h and was much longer than for the standard concrete (2 h). Analyzing the course of abrasive wear of concrete, we can describe two phases: phase I, the wear of the surface (made mainly of cement paste and fine aggregate) and phase II, with constant velocity of wear (because of highest homogeneity of the samples’ core). In case of concrete construction with or without the reinforcement, we cannot clearly isolate the destruction phase. In real environment, there are other corrosion actions besides the abrasive erosion that can mutually amplify itself. The destruction phase is individually defined based on its maximal bearing capacity and individual environmental conditions. Assuming in our general model of abrasive wear of non-reinforced concrete that the environmental conditions are constant and we only take into consideration the concrete wear from abrasion, we can describe the main differences in the course of phase I and phase II for the standard and high-strength concrete. For the standard concrete, the course of wear (Fig. 8) is presented by the following equation: α m λ W(t) = (2) = 1− m0 λ+t where m is the mass decrement after time t, m0 is the initial mass of the sample, α and λ are the material constants determined in experiment and t is the time of abrasion. Reference [12] presents the procedure of determining the α and λ. The time of phase I according to the course of velocity
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Table 4 Relations between underwater abrasion resistance of HSC Concrete
Correlation W = b1 tb2
C1 C2 C3* C4 C5 C6 C7 C8 C9 ∗
W = bt
b1
b2
R2
0.0105 0.0487 0.0720 0.1710 0.0722 0.0236 0.0198 0.1143 0.0068
1.2116 0.9314 0.9772 0.7667 0.8783 0.9461 1.0327 0.6466 1.2105
0.989 0.999 0.991 0.997 0.999 0.999 0.990 0.998 0.997
b
R2
0.259 0.036 0.062 0.062 0.042 0.018 0.023 0.024 0.017
0.991 0.997 0.984 0.984 0.991 0.994 0.986 0.906 0.994
Max R2 = 0.999 for correlation W = b1 + b2 t + b3 t2 .
of wear is around 6 h. During the initial 2 h, a quick increase of velocity VW (accumulation period) was observed. Then comes a very fast decrease of velocity of wear (fading period) that lasts around 4 h. After about 6 h, the wear process stabilizes and then the phase II begins—stable wear of the material. For the examined HSC, the course of wear W(t) can be approximated with the power function, but when we assume the linear course of wear W(t), the obtained values of coefficient R2 are only minimally different (Table 4). Analyzing the run of velocity of wear VW (Fig. 9), we can observe that the velocity increase ends in 12–24 h. In case of concrete with compression strength over 80 MPa (C1, C2), there is no distinct decrease of velocity, only a small one, then the velocity of wear stabilizes. This linear course of wear W(t) starts after 24 h for B1 and B2 concrete and for all other ones between 36 and 60 h. After this period, phase II starts—stable wear of material. If we omit the initial stage of wear (phase I) and assume the linear wear W(t)—the velocity of wear VW will be constant (Fig. 10). All the modelling assumptions need to be verified experimentally. The proposed model of abrasive wear of HSC can be used for preliminary estimation of abrasive wear in hydrotechnic constructions.
Fig. 10. The model of HSC wear without the phase I: W, wear; VW , velocity of wear; t, time.
7. Conclusions From the test results, the following conclusions were formulated: 1. The ASTM C 1138 method is suitable for determination of the abrasion resistance of HSC with a 28-day compressive strength of 80–120 MPa. 2. The examination period of the underwater method for the HSC should be at least 72 h. 3. The assumption of linear dependency of HSC wear is correct, if we omit the initial stage of abrasion—12–24 h for the HSC is omited. The velocity of wear can be assumed constant. All the above assumptions are valid for nonreinforced HSC with compression strength over 80 MPa. 4. The latex additive does not improve the abrasion resistance of concrete. The HSC with added PVC fiber showed improvement in this area.
Acknowledgement The research has been supported by science project of the Minister of Scientific Research and Information Technology State No. 5 T07E 01924.
References
Fig. 9. Velocity of HSC wear. VW , velocity of wear; t, time.
[1] DIN 52108:202-07, Testing of inorganic non-metallic materials – Wear test using the grinding wheel according to B¨ohme – Grinding wheel method. [2] ASTM C 1138-97, Standard test method for abrasion resistance of concrete (underwater method), in: Annual Book of ASTM Standards, vol. 04.02, ASTM, West Conshohocken, 2002. [3] ASTM C 779/C 779M – 00, Standard test method for abrasion resistance of horizontal concrete surfaces, in: Annual Book of ASTM Standards, vol. 04.02, ASTM, West Conshohocken, 2002. [4] O.E. Gjø´ rv, Abrasion resistance of high-strength concrete pavements, ACI Mater. J. 6 (1990) 45–48. [5] T.C. Holland, Erosion resistance with silica-fume concrete, ACI Concr. Int. 3 (1987) 32–40.
El˙zbieta Horszczaruk / Wear 259 (2005) 62–69 [6] N. Ghafoori, B.M. Surandar, Abrasion resistance of concrete block pavements, ACI Mater. J. 1 (1995) 25–36. [7] T.R. Naik, Abrasion resistance of high-strength concrete made with class C fly ash, ACI Mater. J. 6 (1995) 649–659. [8] F. Saucier, Calcium aluminates cement based concretes for hydraulic structures: resistance to erosion, abrasion & cavitation, in: N. Banthia (Ed.), Proceedings of the Third International Conference on Concrete Under Severe Conditions, The University of British Columbia, Vancouver, 2001, pp. 1562–1569. [9] E. Horszczaruk, Abrasive wear of concrete in hydraulic structures, Tribologia 3 (2003) 19–36.
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[10] J.E. McDonald, Evaluation of materials for repair of erosion damage in hydraulic structures, in: Durability of Concrete, Fifth International conference, Barcelona, ACI, SP-192-54, 2000, pp. 887– 898. [11] M. Sonebi, K.H. Khayat, Testing abrasion resistance of high-strength concrete. cement, Concr. Aggregates 23 (2001) 34–43. [12] E. Horszczaruk, The model of abrasive wear of concrete in hydraulic structures, Wear 256 (2004) 787–796. [13] E. Horszczaruk, Wear kinetics of ordinary concrete submit to abrasive erosion, Ochrona przed Korozja 5s/A (2004) 119– 126.