## 2 Experiments  
### Materials and Mixture Proportions  
Table 1 shows the density, specific surface area, and chemical compositions of the mineral additives used in this study. The specific surface areas of OPC, SF, GGBS, and CKD  
were 3350 cm\({}^{2}\)/g, 200,000 cm\({}^{2}\)/g, 4360 cm\({}^{2}\)/g, and 8200 cm\({}^{2}\)/g, respectively. The CKD used in this study also contained very low concentrations of alkali and SO\({}_{3}\) that deteriorate the microstructure. Figure 1 shows the cumulative volume percentages and particle size distribution obtained from the sieving test of the materials. Finally, 2 vol.% of ultra-high molecular PE fibers were incorporated into the mixes.  
Table 2 describes the mix proportions of the cementitious composites used in this study. Four types of reactive materials--Type 1 OPC, GGBS, SF, CKD--and two types of non-reactive materials--silica flour and silica sand--were used. One of the main aims of this study was to identify the influence of the properties of binders on the mechanical behavior of UHP-SHCCs. Thus, the amount of silica sand (fine aggregate) was kept at 30% of the reactive binder materials. Each mixture incorporated only one or two reactive mineral additives to individually examine their influence under the same fabrication and curing conditions. Table 3 summarizes the physical properties of the PE fiber.  
As suggested in Table 2, specimen A only included OPC as a binder, while the mixes D to I additionally contained one of the mineral additives GGBS, SF, and CKD, respectively. Mixes B and C also contained silica flour in a weight ratio of 0.15 and 0.3 to OPC, respectively. They were considered as test variables to clarify the effect of reactive and non-reactive mineral additives. The amount of water and superplasticizer (SP) was controlled not to impact the workability of the mixture. Although the silica flour does not react with water, it considerably decreases the workability. This can cause a severe problem when PE fibers are dispersed in the mixture. Therefore, the amount of water into the mixes B and C was set to 20% of the weight of the silica flour to obtain the proper workability.  
\begin{table}
\begin{tabular}{c c c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Type**} & **Density** & **Specific Surface** & \multicolumn{8}{c}{**Chemical Composition (\%)**} & \\ \cline{3-13}  & **(g/cm\({}^{3}\))** & **Area (cm\({}^{2}\)/g)** & **SiO\({}_{2}\)** & **Al\({}_{2}\)O\({}_{3}\)** & **Fe\({}_{2}\)O\({}_{3}\)** & **CaO** & **MgO** & **SO\({}_{3}\)** & **K\({}_{2}\)O** & **Na\({}_{2}\)O** & **Sum (\%)** \\ \hline OPC & 3.15 & 3350 & 21.01 & 6.40 & 3.12 & 61.33 & 3.02 & 2.30 & - & - & 97.18 \\ SF & 2.20 & 200,000 & 96.00 & 0.25 & 0.12 & 0.38 & 0.10 & - & - & - & 96.85 \\ GGBS & 2.90 & 4360 & 33.00 & 14.00 & 0.50 & 42.00 & 6.31 & 2.01 & - & - & 97.82 \\ CKD & 2.67 & 8200 & 9.65 & 3.70 & 1.54 & 43.60 & 1.40 & 0.77 & 0.35 & 0.06 & 61.07 \\ Silica Sand & 2.65 & - & 99.50 & 0.08 & 0.02 & 0.02 & 0.02 & - & - & - & 99.64 \\ Silica flour & 2.65 & - & 99.80 & 0.06 & 0.04 & 0.02 & 0.02 & - & - & 0.01 & 99.95 \\ \hline \hline \end{tabular}  
* OPC = ordinary Portland cement; SF = silica fume; GGBS = ground granulated blast furnace slag; and CKD = cement kilu dust.  
\end{table}
Table 1: Chemical compositions and physical properties of materials.  
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Type** & **W/B** & **Cement** & **Silica Flour** & **GGBS** & **SF** & **CKD** & **S/B** & **SP \({}^{*}\)** \\ \hline A & 0.22 & & - & - & - & - & 0.010 \\ B & 0.25 & & 0.15 & - & - & - & 0.012 \\ C & 0.28 & & 0.3 & - & - & - & 0.013 \\ D & 0.21 & & - & 0.5 & - & - & 0.016 \\ E & 0.21 & 1.0 & - & 1.0 & - & - & 0.3 & 0.021 \\ F & 0.22 & & - & - & 0.2 & - & 0.012 \\ G & 0.22 & & - & - & 0.3 & - & 0.014 \\ H & 0.22