废胶粉/SBS复合改性沥青及沥青混合料的性能研究

Properties of Waste Rubber Powder/SBS Composite Modified Asphalt and Asphalt Mixtures

采用共混改性制备了废胶粉/SBS复合材料,并对其改性沥青及改性沥青混合料的性能进行了研究。确定了改性沥青中废胶粉/SBS复合材料最佳掺量和最佳工艺参数。试验结果表明在205℃的剪切温度、60 min的剪切时间、7 h的发育时间以及7 000 rmp的搅拌速率下制备改性沥青具有较好的综合性能。随着胶粉在复合材料中的质量比逐渐增加,改性沥青的软化点上升而针入度与延度下降,相对于基质沥青软化点提高了84.8%,而针入度与延度分别降低了16.9%和44.7%。废胶粉/SBS复合材料改性沥青会增大改性沥青的高温稳定性以及低温变形能力,当掺量从1%增加到7%时,稳定度和低温弯曲应变分别增加了77.5%和24.2%,但是会降低改性沥青的水稳定性。

The waste rubber powder/SBS composite material was prepared by blending and modification to study the properties of its modified asphalt and asphalt mixtures,and its optimal content and process parameters were determined.The results showed that the modified asphalt prepared under the conditions of the shear temperature of 205℃,shear time of 60 minutes,developing time of 7 hours,and mixing rate of 7000 rmp had a better comprehensive performance.As the mass ratio of the rubber powder increased within the composite material,the modified asphalt's softening point increased and the penetration and ductility decreased.Compared with matrix asphalt,the softening point increased by 84.8%and the penetration and ductility decreased by 16.9%and 44.7%,respectively.The composite material would increase the modified asphalt's high-temperature stability and low-temperature deformation capacity but decrease its water stability,and the high-temperature stability and low-temperature bending strain increased by 77.5%and 24.2%when the content was increased from 1%to 7%,respectively.