# Preparation and Properties of SBS/REOB-Modified Rejuvenated Asphalt
## 3 Test Method  
### SBS/REOB-Modified Rejuvenated Asphalt Sample Preparation  
Simulated Aging Test of Base Asphalt  
In this paper, the aging method of heating in a laboratory oven was adopted [9], which proceeded as follows: A certain amount of base asphalt was spread on a porcelain plate, and the shallow porcelain plate containing the base asphalt was put into an oven at 160 \({}^{\circ}\)C. The asphalt in the porcelain plate was heated for 48 h in the oven, and the base asphalt was stirred every two hours to prevent the asphalt surface from curing and forming layers, which affects the aging degree of the base asphalt.  
Preparation of SBS/REOB-Modified Rejuvenated Asphalt  
1. REOB rejuvenated asphalt. 1. We heated and melted the aging matrix asphalt in an oven at 150 \({}^{\circ}\)C \(\pm\) 2 \({}^{\circ}\)C until it was in a flowing state. The REOB was placed in the oven at 60 \({}^{\circ}\)C for 20 min (to avoid the influence of the instantaneous large temperature difference when pouring asphalt). 2. According to the test plan, the REOB of the corresponding proportion in the test design was added to the hot aging asphalt, and the glass rod was continuously stirred for 5 min during the process to ensure the material was fully mixed with the asphalt. 3. We stirred at a temperature of 150 \({}^{\circ}\)C and a speed of 2500 r/min for 15 min. 4. Then, we stirred at 4000 r/min for 40 min and at 1000 r/min for 10 min at low speed to remove bubbles. 2. SBS-modified asphalt. 1. The aging matrix asphalt was heated in an oven at 150 \({}^{\circ}\)C \(\pm\) 2 \({}^{\circ}\)C until flowing. 2. We adjusted the speed of the shear machine to 3000 r/min and added SBS or SBS and the stabilizer, successively, within 5 min. Due to the heat release in the process of adding SBS and since the temperature in the process of adding modifier is not easy to control, the next step was to control the shear temperature at 190 \({}^{\circ}\)C. 3. We sheared at a speed of 4500 r/min for 50 min and stirred at a speed of 1000 r/min for 10 min to remove bubbles. 4. Then, we left it to swell and develop at 160 \({}^{\circ}\)C for 1 h. 3. SBS/REOB-modified rejuvenated asphalt.  
The preparation process for composite modified asphalt changed the shear time and shear rate in (c) of (2) SBS-modified asphalt, according to the test plan, and added the following three steps between a and b of (2) SBS-modified asphalt (Figure 2):  
1. EOB was placed in an oven at 60 \({}^{\circ}\)C for 20 min. 2. REOB was first added into the hot aging asphalt, and the glass rod was continuously stirred for 5 min during the process to ensure the material was fully mixed with the asphalt.  
\begin{table}
\begin{tabular}{c c c} \hline
**Project** & **Test Results** & **Normative** \\ \hline Sulfur content (\%) & 99.98 & \(\geq\)99.5 \\ Ash (\%) & 0.0086 & \(\leq\)0.03 \\ Acidity (H\({}_{2}\)SO\({}_{d}\)) (\%) & 0.0024 & \(\leq\)0.003 \\ Organic matter (\%) & 0.0068 & \(\leq\)0.03 \\ Arsenic (AS) content (\%) & 0.0001 & \(\leq\)0.0001 \\ Moisture (\%) & 0.02 & \(\leq\)0.1 \\ Sieve residue (particle size 75 \(\mu\)m\(\sim\)150 \(\mu\)m) (\%) & 0.01 & \(\leq\)0.5 \\ \hline \end{tabular}
\end{table}
Table 4: Technical specifications of sulfur stabilizer.