SBS/纳米SiO_(2)复合改性再生沥青混合料抗裂性能研究

Study on Crack Resistance of SBS/nano-SiO_(2)Compound Modified Recycled Asphalt Mixture

为解决再生沥青混合料抗裂性能不足的问题,选择纳米SiO_(2)和SBS为改性剂,分别制备纳米SiO_(2)改性再生沥青混合料、SBS改性再生沥青混合料、SBS/纳米SiO_(2)复合改性再生沥青混合料和普通再生沥青混合料,对几种混合料进行试验,包括圆盘拉伸试验(DCT)、小梁试验和疲劳试验,以确定不同沥青混合料的抗裂性能。结果表明,使用改性沥青对再生沥青混合料的低温性能和抗疲劳性能有促进作用,且SBS/纳米SiO_(2)复合改性再生沥青混合料的整体抗裂性能最优。为此,建议应用较高掺量旧沥青路面材料(RAP)时,采用SBS/纳米SiO_(2)复合改性沥青会显著改善整体混合料的抗裂性能。

In order to improve the crack resistance of recycled asphalt mixture,the nano-SiO_(2)and SBS are selected as the modifiers to respectively prepare the nano-SiO_(2)modified recycled asphalt mixture,SBS modified recycled asphalt mixture,SBS/nano-SiO_(2)compound modified recycled asphalt mixture and common recycled asphalt mixture.Several recycled mixtures are tested including the disk tensile test,small-beam test and fatigue test to determine the crack resistances of the different asphalt mixture.The results show that the low temperature performance and fatigue performance of recycled asphalt mixture are improved by using the modified asphalts.And the overall crack resistance of SBS/nano-SiO_(2)compound modified recycled asphalt mixture is the best.Therefore,it is proposed that when the high content of old asphalt pavement material is adopted,the use of SBS/nano-SiO_(2)compound modified asphalt will obviously improve the overall crack resistance of the concrete.