## 1 Introduction  
Adding various modifiers with excellent performance and moderate price in asphalt is an effective method to enhance asphalt performance. The modifiers refer to the natural, synthetic organic, or inorganic materials added to asphalt binder, including fibers, resin, high-molecular polymer, natural asphalt, ground rubber powder, or other materials, which can be melted and dispersed in asphalt binder to improve the performance of asphalt mixture pavement [1; 2; 3; 4; 5; 6]. At present, modified asphalt has made great progress, and products with excellent properties such as styrene-butadienestyrene (SBS) and styrene butadiene rubber (SBR) polymer modifier are widely used. With the progress of materials science and the improvement of experimental conditions, new materials were used as modifiers to prepare new modified asphalt binders. In terms of physical modification methods, nano-CaCO\({}_{3}\), CaCO\({}_{3}\) whiskers, and aramid fibers are the representatives of these emerging modified materials. The three materials have different shapes and belong to nanometers, micrometers, and millimeters, respectively. In this study, these three different scale materials were used to prepare modified asphalt in order to explore the effects of different reinforcements on the performance of modified asphalt from the perspective of composite materials. With the rapid development of nanomaterials, nano-CaCO\({}_{3}\) has been used as a stable and inexpensive material to prepare modified asphalt. [PERSON] et al. added nano-CaCO\({}_{3}\) to asphalt mixture and the test showed that nano-CaCO\({}_{3}\) modified asphalt can improve the high-temperature resistance of rutting and water stability of asphalt mixture, and it is suitable for highway construction in hot and humid areas [7]. [PERSON] et al. found that nano-CaCO\({}_{3}\) can be uniformly dispersed in SBS-modified asphalt, which can improve the toughness, strength, and thermal stability of modified asphalt [8]. [PERSON] et al. found that nano-CaCO\({}_{3}\) increased the wettability of asphalt binder to aggregate [9]. Nano-CaCO\({}_{3}\) was used by [PERSON] et al. to improve the dynamic stability and high-temperature performance of asphalt concrete AC-13 [10]. [PERSON] et al. used 2% and 4% nano-clay in asphalt binder, and the complex shear modulus of modified asphalt increased by 66% and 125%, respectively [11]. The above studies showed that nano-CaCO\({}_{3}\) as a reinforcement can improve the high-temperature performance of asphalt mixtures. Whiskers are high-purity fibrous single crystals and they have excellent mechanical and physical properties due to its nearly complete crystal structure. Whiskers have been widely used in environmentally friendly coatings, building materials, and other fields [12; 13; 14; 15; 16; 17]. [PERSON] et al. found that CaCO\({}_{3}\) whiskers can improve the high-temperature stability in high-modulus asphalt mixture [18]. [PERSON] et al. studied hybrid fibers containing polyester fibers and CaCO\({}_{3}\) whiskers to improve the toughness and mechanical properties of cement slurries [19]. [PERSON] et al. applied various mixed CaCO\({}_{3}\) whiskers added to cement concrete and found that CaCO\({}_{3}\) whiskers had crack resistance in cement concrete [20; 21]. [PERSON] et al. incorporated polyvinyl alcohol (PVA) fibers and CaCO\({}_{3}\) whiskers into multi-scale engineered cementitious composite (MS-ECC). The results showed that the ductility of MS-ECC could be improved by the appropriate addition of CaCO\({}_{3}\) whiskers [22]. [PERSON] et al. found that CaCO\({}_{3}\) whiskers could improve the high-temperature performance of asphalt [23]. [PERSON] et al. showed that CaCO\({}_{3}\) whiskers could effectively improve the strength of oil well cement [24]. Compared with other organic fibers, aramid fibers have advantages in tensile strength and high temperature resistance, but there are limited studies on modified asphalt with chopped aramid fibers. [PERSON] et al.