Influence of Addition Process on Rheological and Road Performance of High-Content SBS Modified Asphalt

CHAI Chongchong; HUNAG Weidong; WANG Qiang; CAI Ming; CAO Yadong

doi:10.3969/j.issn.1007-9629.2025.11.009

Abstract：The material addition process has a crucial effect on the performance of modified asphalt.A series of high content SBS modified asphalt(HCBMA)was prepared by using four addition process,including the oil-filled premixing,granulating premixing,simultaneous addition and subsequent addition,and a multi-angle evaluation method was adopted for the research.The results show that the addition process can significantly affect the performance of HCBMA.The absorption of rubber oil by high content SBS and base asphalt has a competitive relationship.HCBMA prepared by oil-filled premixing has the best high temperature rheological properties,the simultaneous addition process shows the best fatigue resistance,but the fatigue performance of the granulation premixing process(two-screw extrusion granulation)is the weakest.High temperature performance of the subsequent addition process is the lowest,while the low temperature performance indicators are the best.Compared with the oil-filled premixing/simultaneous premixing/subsequent addition process,HCBMA prepared by the granulation premixing process shows the smallest molecular weight,polydispersity index and aging index,which means the degradation degree of SBS is relatively deep during the preparation process.Asphalt mixture is prepared by the oil-filled premixing process has the high temperature rutting and low temperature cracking resistance,while the simultaneous addition process shows the opposite phenomenon.Considering the performance of asphalt and mixtures,it is recommended to adopt the oil-filled premixing process.It is also necessary to combine rheological properties and asphalt mixture performance due to the conventional performance evaluation method of HCBMA is insufficient.