## Materials and Methods
### ASTM C1138 Test Method  
The ASTM C1138 (1997) \"Standard Test Method for Abrasion Resistance of Concrete (Underwater Method)\" test method is intended to qualitatively simulate the behavior of swirling water containing suspended and transported solid objects that produce abrasion of concrete and cause  
\begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline
**Materials** & **SiO\({}_{2}\)** & **Al\({}_{2}\)O\({}_{3}\)** & **CaO** & **Fe\({}_{2}\)O\({}_{3}\)** & **Na\({}_{2}\)O** & **K\({}_{2}\)O** & **SO\({}_{3}\)** & **MgO** \\ \hline Cement & 20.9 & 5.6 & 63.9 & 3.1 & – & – & 2.5 & 2.9 \\ GGBFS & 33.7 & 13.7 & 42.1 & 1.2 & 0.29 & 0.3 & 1.87 & 6.53 \\ Silica fume & 93.2 & 0.1 & 0.9 & 0.04 & 0.6 & 2.0 & 0.005 & 0.5 \\ \hline \hline \end{tabular}
\end{table}
Table 1: Chemical compositions of cement, GGBFS, silica fume (%).  
\begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline
**Fiber Shape** & **Coating** & **Diameter, mm** & **Length, mm** & **Tensile Strength, MPa** & **Specific Gravity** \\ \hline End-hooks & Brass & 0.75 mm & 30 & 1050 & 7.8 \\ \hline \hline \end{tabular}
\end{table}
Table 2: Properties of steel fibers.  
\begin{table}
\begin{tabular}{c c c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Batch**} & \multirow{2}{*}{**w/cm**} & \multicolumn{8}{c}{**Quantities, kg/m\({}^{3}\)**} & \multirow{2}{*}{**Slump, cm**} & \multirow{2}{*}{**Compressive Strength, MPa**} \\ \cline{3-3} \cline{5-12}  & & & **Water** & **Cement** & **GGBFS** & **SF** & **Steel Fiber** & **Sand** & **Gravel** & **SP** & **Slump, cm** & **Compressive Strength, MPa** \\ \hline C28 & 0.28 & 160 & 457 & 114 & 0 & 0 & 730 & 925 & 12.5 & 24 & 90.8 \\ C36 & 0.36 & 160 & 356 & 89 & 0 & 0 & 780 & 985 & 10.9 & 22 & 50.3 \\ C50 & 0.50 & 160 & 288 & 32 & 0 & 0 & 840 & 1055 & 0.5 & 21 & 30.4 \\ SC36 & 0.36 & 160 & 285 & 71 & 89 & 78 & 755 & 945 & 15 & 18 & 51.0 \\ \hline \hline \end{tabular}
\end{table}
Table 3: Concrete mixture proportions and results of compressive strength.  
produces and related effects. The wearing action caused by rolling steel balls simulates the friction action of waterborne particles on concrete surfaces, but not the impact action [14].  
The apparatus components are outlined as follows: a drill press; an agitation paddle; a cylindrical steel container, measuring \(305\pm 6\) mm (inside diameter) \(\times\)\(450\pm 25\) mm (height), housing a disk-shaped concrete specimen; and 70 steel grinding balls of various size (ten 25-mm-diameter balls, thirty-five 19-mm-diameter balls, and twenty-five 13-mm-diameter balls). The water in the container is circulated by the immersed agitation paddle powered by the drill press rotating at a speed of \(1200\pm 100\) rpm. The circulating water, in turn, moves the steel grinding balls on the concrete surface, producing the desired abrasion effects.  
The underwater friction abrasion test involved six 12 h periods for a total of 72 h. At the end of every 12 h of operation, the specimen was removed from the test container, the abraded material was flushed off, and the surface was dried. This study determined and recorded the specimen mass in air to the nearest 10 g. The abrasion loss (percent by mass), friction abrasion rate (FAR, in g/h), and average FAR was determined from the specimen mass loss versus mass before test, mass loss versus test period, and total mass loss versus test time, respectively. A minimum of three specimens were used to establish the FAR. The range among the test results for the three specimens should be no greater than 46% of their average.