橡维联/纳米膨润土复合改性沥青混合料的路用性能研究

Study on road performance of rubber dimensional/nano-bentonite composite modified asphalt mixture

为了分析纳米有机膨润土复合改性沥青混合料的路用性能,采用改性剂橡维联和纳米有机膨润土对沥青进行复合改性,分别对沥青混合料的高温稳定性、低温抗裂性、水稳定性及耐疲劳性能进行研究,并通过灰色关联度评价不同掺量的橡维联对沥青混合料路用性能的影响。研究结果表明:复合改性能提高混合料的动稳定度,其高温稳定性相较于只添加膨润土的沥青混合料提高20%左右;复合改性能提高混合料的极限弯拉应变,其低温稳定性相较于只添加膨润土的沥青混合料至少提高23%;复合改性对水稳定性和耐疲劳性都有改善;且通过研究不同掺量的橡维联的沥青混合料和各项路用性能的灰色关联度表明:橡维联/纳米膨润土对沥青影响程度大小依次为:低温抗裂性>高温稳定性>耐疲劳性>水稳定性。当纳米膨润土掺量4%,橡维联掺量为1‰时,沥青混合料的路用性能最佳。

In order to analyze the road performance of nano-organic bentonite composite modified asphalt mixture,the modified rubber dimensional and nano-organic bentonite were used to modify the asphalt,and study the high temperature stability,low temperature crack resistance,water stability and fatigue resistance of the asphalt mixture separately.The grey correlation evaluation method was used to evaluate the effect of different content of rubber dimensional on the road performance of asphalt mixture.The results show that the composite modification can improve the dynamic stability of the mixture,and its high temperature stability is about 20%higher than that of the asphalt mixture with only bentonite.The composite modification can improve the ultimate bending strain of the mixture and its low temperature stability.Com⁃pared with asphalt mixture only with bentonite,it increases by at least 23%;The composite modification has improved water stability and fatigue resistance.By studying the asphalt mixture of different dosages of rubber and the grey correla⁃tion of various road performance,it shows that the influence degree of the rubber dimensional/nano bentonite on the as⁃phalt is low temperature crack resistance>high temperature stability>fatigue resistance>water stability.When the amount of nano-bentonite is 4%and the amount of rubber dimensional mixture is 0.1%,the asphalt pavement has the best road performance.