【摘要】 本工作对泡沫沥青的设计优化和冻融循环后泡沫沥青混合料的路用性能进行了研究。采用自行设计的室内沥青发泡机,结合70#基质沥青最佳发泡条件的发泡温度为159℃,搅拌速率为1 156 r/min,研究了发泡用水量对发泡效果的影响,并采用硅烷偶联剂对沥青进行改性,制备了4种沥青混合料。结果表明,泡沫沥青的针入度随着发泡用水量的增加而增大,软化点、延度和粘度均随着用水量的增加而减小;冻融循环30次时,硅烷偶联剂改性泡沫沥青相对于改性前的泡沫沥青的高温稳定性提高了20.63%,低温抗裂性提高了28.51%,水稳定性提高了20.14%;改性泡沫沥青高温性能、低温抗裂性和水稳定性相对稳定;硅烷偶联剂改性泡沫沥青粘结力有所增强,改善了泡沫沥青内部由水导致的粘结力下降的问题。更多还原

【Abstract】 In this paper,the design optimization of foam asphalt and the road performance of foam asphalt mixture after freeze-thaw cycles were studied.Using the self-designed asphalt foaming machine,combined with the optimal foaming conditions,the foaming temperature was 159 ℃ and the stirring rate was 1 156 r/min,of 70# base asphalt,the influence of foaming water consumption on foaming effect was studied,and four kinds of asphalt mixtures were prepared by modifying asphalt with silane coupling agent. The results showed that the penetration degree of foam asphalt increased with the increase of foaming water consumption,and the softening point,ductility and viscosity decreased with the increase of water consumption. When the freeze-thaw cycle is 30 times,compared with the none modified mixture,the high-temperature stability,low-temperature crack resistance and water stability of the foam asphalt modified by silane coupling agent increased by 20.63%,28.51% and 20.14%. The modified asphalt foam had high temperature performance,low temperature crack resistance and the water stability is relatively stable. The adhesion strength of modified asphalt foams with silane coupling agent has been enhanced,and the problem of the decrease of cohesive force caused by water inside the foamed asphalt has been improved.更多还原