# Investigation of the Performance of Basalt Fiber Reinforced Asphalt Mixture
## 2 Materials and Methods
### Sample Preparation  
The traditional AC-13 asphalt mixture is frequently used in the construction of asphalt pavement. In this study, the effect of basalt fiber on the performance of AC-13 was investigated. The gradation of the AC-13 asphalt mixture was given in Table 6 and Figure 2. The basalt fiber was added in the AC-13 asphalt mixture as an additive, and the proportions of basalt fiber in the AC-13 asphalt mixture were 0%, 0.2%, 0.3%, 0.4% and 0.5% by weight. The optimum content of polyester fiber and lignin  
\begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Indicators**} & **Unit** & **Test Results** & **Test Basis** \\ \hline Penetration (25 \({}^{\circ}\)C, 100 g, Ss) & 0.1 & 65 & ASTM D5-97 \\ Softening point & \({}^{\circ}\)C & 76 & ASTM D36-06 \\ Ductility (5 \({}^{\circ}\)C, 5 cm/min) & cm & 48 & ASTM D113-99 \\ Elastic recovery (25 \({}^{\circ}\)C) & \% & 98.5 & ASTM D3344-90 \\ Solubility (trichloroethylene, \%) & \% & 99.82 & ASTM D70-76 \\ Flash point & \({}^{\circ}\)C & 356 & ASTM D92-02 \\ \hline \multicolumn{3}{c}{RTFOT (163 \({}^{\circ}\)C, 75 min)} \\ \hline Mass loss & \% & 0.03 & ASTM D2872-04 \\ Penetration ratio (25 \({}^{\circ}\)C) & \% & 71 & ASTM D5-97 \\ \hline \hline \end{tabular}
\end{table}
Table 1: SBS-modified asphalt test results and technical indicators.  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Characteristics**} & **Unit** & **Technical Standard** & **Test Results** \\ \hline Apparent specific gravity & g/cm\({}^{3}\) & \(\geq\)2.50 & 2.731 \\ Sturdiness & \% & \(\leq\)12 & 2 \\ Angularity & \% & \(\geq\)30 & 34.9 \\ \hline \hline \end{tabular}
\end{table}
Table 4: Physical characteristics of mineral filler.  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Characteristics**} & **Unit** & **Technical Standard** & **Test Results** \\ \hline Apparent specific gravity & g/cm\({}^{3}\) & \(\geq\)2.50 & 2.731 \\ Sturdiness & \% & \(\leq\)12 & 2 \\ Angularity & \% & \(\geq\)30 & 34.9 \\ \hline \hline \end{tabular}
\end{table}
Table 3: Physical characteristics of fine aggregate.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Characteristics**} & **Unit** & **Technical Standard** & **Test Results** \\ \hline Apparent specific gravity & g/cm\({}^{3}\) & \(\geq\)2.50 & 2.730 \\ Hydrophilic coefficient & - & \(<\)1 & 0.9 \\ Plasticity index & \% & \(<\)4 & 2.3 \\ \hline \hline \end{tabular}
\end{table}
Table 5: Main characteristics of basalt fiber, polyester fiber and lignin fiber.  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Type**} & **Diameter** (\(\mu\)m)** & **Length** (mm) & **25 \({}^{\circ}\)C** & **Tensile** & **Melt** \\  & **(\(\mu\)m)** & **(mm)** & **Relative** & **Strength** (MPa)** & **Temperature** (\({}^{\circ}\)C)** \\ \hline Basalt fiber & 11–13 & 1.5 & 2.416 & \(>\)2000 & 1500–1600 \\ \hline Polyester fiber & 20 & 6 & 1.317 & 570 & 260 \\ \hline Lignin fiber & 45 & 1.1 & 0.830 & 110 & \(>\)1000 \\ \hline \hline \end{tabular}
\end{table}
Table 5: Stable characteristics of basalt fiber, polyester fiber and lignin fiber.  
fibers in asphalt mixtures were 0.2% and 0.3%, which was provided by the manufacturer. In order to make the fibers dispersed evenly, basalt fiber asphalt mixture was prepared by the dry-mix method. At first, the fiber mixed with the aggregate in a rotary mixer for 90s to reduce the clumping or balling of fibers. Then, the asphalt and mineral filler were added, and the mixture was blended at 75 rpm for 180 s. The prepared mixture was placed in molds by the compaction method. Each sample extruded from the mold prior to the test after curing for 24 h.