## 1 Introduction
(2018) added BF to asphalt mortar and conducted softening point, cone penetration, viscosity, force extension, DSR (Dynamic Shear Rheometer), and BBR (Bending Beam Rheometer) tests. The results showed that the incorporation of BF improved the high-temperature and low-temperature performance of the asphalt mastic. Through analyzing the mixture's microstructure and morphology by scanning electron microscopy technique, [PERSON] et al. [PERSON] et al. (2018) studied the effect of BF length and content on the performance of asphalt mortar. The microstructure and morphology of the mixture were analyzed by scanning electron microscopy. The results showed that the BF formed a three-dimensional network of dispersed stress in the asphalt mortar, which inhibited the crack development of the asphalt mortar, thereby improving the crack resistance. [PERSON] et al. [PERSON] et al. (2018) analyzed the impact of basalt fibers on the toughness of AC-13 and SMA-13 asphalt mixtures. Through indirect tensile and scanning electron microscope tests, the effect of fiber on the toughness of the mixture and the toughening mechanism were analyzed. According to the research status of the low-temperature stability of BF, it could be found that the improvement mechanisms of BF on the asphalt mixture was that it formed a three-dimensional spatial grid structure, strengthened the toughness, and inhibited the propagation of cracks. [PERSON] et al. [PERSON] et al. (2018) found that the fatigue failure of the asphalt mixture was mainly caused by the damage to the asphalt mortar, and that the addition of BF in asphalt mortar could effectively extend its fatigue life. [PERSON] et al. (2018) studied the road performance and low-temperature characteristics of BF SMA-13 through low-temperature splitting, trabecular bending, and stress relaxation tests. The results showed that BF improved the low-temperature performance of the asphalt mixture. [PERSON] et al. [PERSON] et al. (2018) studied the effects of BF on the asphalt binder and cement through fatigue tests. The BF released the stress concentration in the interface area of the two fillers, alleviated the fatigue damage caused by the cyclic load, and enhanced the antifatigue performance. [PERSON] et al. [PERSON] et al. (2018) tested the performance of the BF asphalt mixture through DSR and repeated creep tests. The results showed that the BF-modified asphalt mastic had a high rutting factor and strong resistance to deformation at high temperatures. [PERSON] et al. (2018) studied the performance of the BF-modified asphalt mixture through a low-temperature split test, and the toughness index showed that the low-temperature crack resistance of BF-modified asphalt mixture was significantly improved. Based on the three-dimensional model and numerical analysis, [PERSON] et al. [26; 27] studied the rheological and viscoelastic properties of basalt-fiber-reinforced asphalt mastic and mortar. The numerical analysis showed that the BF caused the stress redistribution of the asphalt mortar and reduced the stress of the asphalt mortar. Compared with conventional regression model approach, the response ratio optimized by the response surface method is more accurate and is becoming increasingly popular in the construction industry [28]. The response surface method is a collection of statistical methods used for designing experiments, developing models, assessing the effects of the experimental factors, and optimizing the process [29; 30]. [PERSON] et al. [31] used the response surface methodology to study the effects of basalt fiber content, length, asphalt-aggregate ratio, and other factors on the volume and strength properties of SBS-modified asphalt mixture. [PERSON] et al. [32] applied the response surface method to evaluate the aging responses of asphalt binder. [PERSON] et al. [33] introduced the response surface method into the mix design for an asphalt mixture.