高寒高海拔地区TOR/胶粉改性沥青老化性能评价

Aging Performance Evaluation of TOR/Rubber Powder Modified Asphalt in High Altitude and Cold Regions Area

为更好地促进高寒高海拔地区橡胶粉改性沥青的工程化应用,使用胶粉、TOR/胶粉制备了胶粉改性沥青(CRMA)与TOR/胶粉改性沥青(TOR-CRMA),并与SK 90^(#)基质沥青(VGA)在短期老化条件下测试其软化点、胶粉降解率,在长期老化条件下(室外暴晒、模拟室外老化)测试其针入度(25℃)、软化点、延度、劲度模量、抗剪强度等指标;分析其稠度、黏度、延性、耐老化等路用性能。结果表明:TOR-CRMA的路用性能提升效果较为显著,且减少了老化过程中的胶粉降解;随老化时间的延长,三种沥青路用性能均下降,但于老化初期CRMA、TOR-CRMA的软化点均下降,后随老化时间而迅速上升;其与老化初期改性沥青体系微观上主要表现为交联结构的瓦解有关。

In order to promote the engineering application of rubber powder modified asphalt in cold and high altitude areas,rubber powder modified asphalt(CRMA)and TOR/rubber powder modified asphalt(TOR-CRMA)were prepared by rubber powder and TOR/rubber powder,and the softening point and degradation rate of rubber powder were tested together with SK 90^(#)matrix asphalt(VGA)under short-term aging condition.The needle penetration(25℃),softening point,elongation,stiffness modulus,shear strength and other indexes were tested under long-term aging conditions(outdoor exposure,simulated outdoor aging).The road performance such as consistency,viscosity,ductility and aging resistance were analyzed.The results showed that TOR-CRMA significantly improved the road performance and reduced the degradation of rubber powder during the aging process.With the extension of aging time,the pavement performance of three kinds of asphalt decreases,but the softening point of CRMA and TOR-CRMA decreases at the initial stage of aging,and then increases rapidly with aging time.It is related to the breakdown of the crosslinking structure in the microstructure of the modified asphalt system at the early stage of aging.