## 1 Introduction  
In recent years, SBS-modified asphalt has attracted significant attention as an important road material [1, 2]. Its unique properties enable roads to maintain excellent elasticity and durability under different climate and load conditions [3, 4]. However, the preparation process of SBS-modified asphalt plays a crucial role in achieving these advantages [5, 6, 7]. Inprevious studies, scholars have extensively explored various preparation factors to ensure optimal performance, as shown in Table 1[8; 9; 10; 11; 12]. Optimization of process parameters is one of the key factors in enhancing the performance of SBS-modified asphalt [14; 15]. Variations in SBS dosage, addition time, and mixing speed directly impact the performance of SBS-modified asphalt [16; 17; 18; 19]. By optimizing the SBS dosage, it is possible to increase the material's elastic modulus without affecting the fundamental properties of the asphalt, thus improving the road's resistance to deformation and extending its lifespan [20]. Precise adjustment of the modifier addition time and mixing speed parameters ensures the even dispersion of SBS in the asphalt, thereby enhancing the asphalt's crack resistance, elasticity, and deformation capabilities [21]. Furthermore, control over the mixing temperature is also crucial for the success of the modification process [22; 23]. During preparation, an appropriate mixing temperature can facilitate a thorough blending of SBS and asphalt, ensuring the effectiveness of their interaction [24]. Too low a temperature can result in incomplete dispersion of the SBS polymer in the asphalt, impacting material performance [25]. Conversely, excessively high temperatures can lead to polymer degradation, thereby reducing the modification's effectiveness [26]. Therefore, researchers must accurately control the mixing temperature during the process to ensure optimal modification effects. The optimization of polymer dispersion in the preparation process directly influences the overall performance of SBS-modified asphalt [27; 28]. Therefore, polymer dispersion is a critically important consideration. By using suitable dispersing agents and mixing processes, it is possible to minimize the formation of polymer aggregates, thus enhancing the material's uniformity. Similarly, optimizing the dispersion process ensures the even distribution of SBS polymers within the asphalt matrix, significantly boosting the material's stability and performance. By selecting appropriate dispersing agents and optimizing the mixing process, it is possible to effectively reduce the formation of polymer aggregates, greatly enhancing the material's uniformity [29; 30]. In conclusion, the performance advantages of SBS-modified asphalt largely depend on the optimization of its preparation process. Adjustments to process parameters, polymer dispersion, and the control of mixing temperatures all play crucial roles in ensuring the exceptional performance of the final product. In-depth research into these key factors can support the continuous optimization of SBS-modified asphalt materials, providing more durable and reliable materials for road construction. Building upon the extensive work of previous researchers, this paper proposes the pre-shredding of the SBS modifier as a replacement for the high-speed shearing step, focusing on the pre-shredded particle size and mixing time parameters of the SBS. In order to compare the microstructural and rheological properties of pre-shredded SBS-modified asphalt with those of asphalt prepared using conventional methods and to optimize the pre-shredded particle size and mixing time parameters, laser confocal microscopy experiments