## 1 Introduction  
With the rapid growth of the car ownership in recent decades, a large number of waste rubber tires are produced every year, which seriously polluted the environment and occupied arable land. Therefore, it has been an urgent problem to recycle and reuse these waste tires, in which crushing waste tires into rubber powder or rubber particles and applying them to the highway construction industry has become one of the main development directions of waste tire treatment [1; 2]. [PERSON] et al. [3] evaluated the effect of crumb particles on rutting resistance and viscosity-temperature susceptibility base on temperature-frequency oscillation and multiple stress creep and recovery tests. The results showed that the finer the crumb rubber particles in the gradation, the better the rutting resistance and the lower the viscosity-temperature sensitivity. [PERSON] et al. [4] and [PERSON] et al. [5] pointed out that crumb rubber particle size had an important impact on the low-temperature performance of asphalt mixtures. [PERSON] et al. [6] and [PERSON] et al. [7] reported that crumb rubber could reduce the low-temperature creep stiffness and resilient modulus of crumb rubber modified asphalt. In addition, with the decrease of the particle size of rubber particles, crumb rubber modified asphalt had been proved to have better low-temperature properties, elasticity and adhesion [8; 9]. [PERSON] et al. studied the influence of styrene-butadiene-styrene (SBS) and rubber powder on the high and low temperature performance of asphalt by the dynamic shear rheometer (DSR) and the bending beam rheometer (BBR) [10; 11]. The results showed that SBS and rubber powder could improve the high temperature performance of asphalt mixture, and rubber powder can significantly reduce the stiffness of asphalt [10]. [PERSON] et al. [12] claimed the combination of crumb rubber particles and SBS copolymers had a synergistic effect on asphalt's rheological properties. [PERSON] et al. [13] pointed out that mechanical properties and anti-icing performance of the control asphalt mixture could be improved by crumb rubber and diatomic. It can be found that rubber particles alone in asphalt mixture may have adverse effects on the performance of asphalt mixture. By comparison, diatomic, as a good inorganic modifier, is often employed to enhance the road performance of mixtures [14]. [PERSON] et al. [15] claimed that adding diatomic in asphalt could reduce the equivalent brittle point of asphalt and reinforce the low-temperature properties of asphalt. [PERSON] et al. [16] pointed out that the moisture susceptibility and the high-temperature stability of asphalt mixtures could be improved by adding the diatomic into asphalt mixtures, but their crack and fatigue resistance could not be improved. [PERSON] et al. [17] reported that the resistance cracking at low temperature of diatomic reinforced asphalt mixtures was better than that of base asphalt mixtures. Some studies have also pointed out that the combined use of diatomic and other modifiers can further reinforce the road properties of asphalt mixtures [18; 19; 20]. Some recycled materials such as plastic waste and jet grouting waste could also be used to enhance the performance of asphalt or asphalt mastics [21; 22]. It can be seen from the above literatures that the current researches on rubber particle modified asphalt mixture are mainly focused on conventional road performance and deicing characteristics. Moreover, it is rare to analyze the effect of diatomic and rubber particle on the viscoelastic properties of asphalt mixtures, and the effect of gradation and asphalt types on the pavement performance and viscoelastic properties of rubber particles and diatomic compound modified asphalt mixtures have not been reported in the previous literature.