# Evaluation of Anti-Skid Performance of Asphalt Mixture Based on Accelerated Loading Test
## 2 Methods
### Experimental Procedures  
The MLS11 accelerated loading test comprises a series of distinct steps, which include the formation of slab specimens for polishing, the processing of standard test pieces, the installation of said test pieces, the adjustment of equipment parameters, the actual loading test, and the subsequent collection of anti-skid data. The following sections delineate these steps in detail. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Test Number** & **Mixture Type** & **Gradation** & **Aggregate Type** & **Oil-Stone Ratio** \\ \hline S1 & AC-16 & Coarse & Diabase & 4.4 \\ \hline S2 & AC-16 & Coarse & Diabase & 4.9 \\ \hline S3 & AC-16 & Coarse & Diabase & 5.4 \\ \hline S4 & AC-16 & Coarse & Diabase & 4.9 \\ \hline S5 & AC-16 & Medium & Andesite & 4.9 \\ \hline S6 & AC-16 & Coarse & Limestone & 4.9 \\ \hline S7 & SMA-13 & Coarse & Diabase & 5.8 \\ \hline S8 & SMA-13 & Medium & Diabase & 6.0 \\ \hline S9 & SMA-13 & Medium & Diabase & 6.2 \\ \hline S10 & SMA-13 & Coarse & Diabase & 5.8 \\ \hline S11 & SMA-13 & Medium & Andesite & 5.8 \\ \hline S12 & SMA-10 & Medium & Diabase & 6.3 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Experiment plan. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Test Index** & **Andesite** & **Diabase** & **Limestone** \\ \hline Crush value/\% & 9.4 & 13 & 20.4 \\ \hline Abrasion value/\% & 10.6 & 14.3 & 23.7 \\ \hline Polishing value/\% & 46 & 44 & 38 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Coarse aggregate technical index test results. Figure 3: Asphalt mixture grading. 1. Preparation of the test sample In accordance with the T0703 test method specified in the \"Highway Engineering Asphalt and Asphalt Mixture Test Regulations\" (JTGE20-2011), the rut plate specimen for the asphalt mixture was prepared via the wheel rolling method, with dimensions of \(300\text{ mm}\times 300\text{ mm}\times 50\text{ mm}\). Subsequently, the rut plate was cut into test slabs of \(150\text{ mm}\times 150\text{ mm}\times 50\text{ mm}\) using a cutting machine. 2. Specim installation The standard test piece for asphalt mixture specified in the test plan should be installed in the test tank with utmost care. It should be noted that the height of the test piece may not be uniformly level during the installation process. To address this issue, the thickness of the steel plate beneath the test piece should be adjusted continuously until all three test pieces are aligned at the same level. Concurrently, the ends and nuts on both sides of the test mold must be tightened securely to prevent significant deviations of the test piece during the loading process. 3. Loading test 1 Load setting: In light of the most severe loading scenario, the maximum load of 2.7 kN is adopted for this test, and the wheel load calibrator is utilized to calibrate the load prior to testing. According to the stipulations, if the standard axle load is 100 kN for a single axle double wheelset and the load on a tire is 25 kN, the load for the accelerated loading test meets the requirements if it is reduced to 2.7 kN using a comparable constant of 1/9. 2 Tire pressure: The test tire inflation pressure is 700 kPa. 3 Loading speed: The loading speed of the test adopts a maximum speed of 2.5 m/s (9 km/h), the frequency of the motor is 48 Hz, and the number of loads per hour is 7200. 4 Test temperature: The test is conducted under ambient temperature conditions, with a range of 20-25 \({}^{\circ}\)C. To maintain a consistent temperature for each test, the laboratory air conditioning temperature is set to 25 \({}^{\circ}\)C. The selected temperature range is representative of typical ambient temperatures that are suitable for both dry and wet states. 5 Dry and wet states: In order to simulate the humid conditions that are typical of hot and humid regions, water is added to the test tank during the accelerated loading test. 6 Number of loading times: The number of loading times varies from 0 to 600,000 cycles.