Study On Performances Of CaSO₄ Whiskers Modified Bitumen

The surface of bitumen pavement is always affected by climate factor and some kinds of load that lead to some road diseases such as crazing, relaxing, distortion and so on. Modified bitumen is the virtual way to resolve these road diseases. With the development of traffic constructing and application of different modified bitumen widely, the performance of surface of bitumen pavement is improved evidently. According to material character of CaSO₄ whiskers, it is possible of applying the CaSO₄ whiskers to bitumen.According to techniques of polymer modified bitumen, a principle of preparing technique for CaSO₄ whiskers modified bitumen is introduced on which the emulsion method and mechanical mixing method are used in this study. With respect to the performance of modified bitumen, emulsion method is more suitable to CaSO₄ whiskers than mechanical mixing method. But these two methods can all be applied to CaSO₄ whiskers modified bitumen because of the small performance difference of Modified Bitumen gotten in the two methods.From the relation between the amount of CaSO₄ whiskers and the performance of modified bitumen, it is concluded that the appropriate content of CaSO₄ whiskers in original bitumen is 5-9% above which CaSO₄ whiskers can not improve the performance of bitumen, in which the stability in high temperature and anti-split in low temperature can be increased, temperature response can be improved.Considering the results, modified mechanism is discussed from containing ability and relation of whiskers shape and performance of modified bitumen.The key factor of the CaSO₄ whiskers function is that the whiskers interlaced dispersing in bitumen forming structure of dimensional grille and the structure of CaSO₄ whiskers — stearic-acid — bitumen.The study will settle the foundation for the development of new type, environmental and cheaper mineral stuffing bitumen modified material.