温拌—再生改性沥青SMA混合料性能研究

Properties of Warm Mix-Recycled Modified Asphalt SMA Mixture

目的研究温拌—再生改性沥青SMA混合料的路用性能和疲劳性能,为温拌—再生技术在工程中的应用提供有价值的数据和理论依据.方法采用马歇尔配合比设计方法进行设计.对旧路沥青混合料和既添加再生剂又添加温拌剂的温拌—再生沥青混合料的各项性能指标进行对比研究.结果确定了温拌—再生改性沥青SMA混合料的最佳拌合温度为140℃.温拌—再生改性沥青SMA混合料的动稳定度为7 450次/mm,残留稳定度为87.3%,冻融劈裂强度比为84.7%,都高于规范要求.在4种应力比下温拌—再生改性沥青SMA混合料的疲劳寿命都高于旧沥青混合料.结论在降低拌合温度的情况下,温拌—再生沥青混合料的力学性能和路用性能可以满足规范要求.抗水损害和抗疲劳性能都得到了提高,冬季现场热再生施工期得到了延长.改性沥青SMA混合料的温拌—再生技术具有很广阔的应用前景.

The purpose of this paper is to find out the valuable data and theoretical basis for the application of warm mix-recycled technology on engineering according to the study of the pavement performance and fatigue property of warm mix-recycled modified asphalt SMA mixture. Marshall Test Design methods of asphalt mixtures are used to design the warm mix-recycled asphalt mixture. This paper offers a comparative study on each performance index of old pavement asphalt mixture and warm mix-recycled asphalt mixture both add regenerant and warm mix agent. As the result of that we determined the best mixing temperature of warm mix-recycled modified asphalt SMA mixture is 140 . The dynamic stability is 7 450 times/mm, the residual stability is 87.3 % and the intensity ratio of frozen and melted is 84.7 %. Both of these indexes are all higher than standard requirements. The fatigue life of warm mix-recycled modified asphalt SMA mixture is higher than old asphalt mixture under four different stress ratios. The conclusion is that under the circum- stance of reducing the mixing temperature, the mechanical properties and performance of warm mix-recycled asphalt mixture can meet the standard requirements. Both the anti-water damage property and anti-fatigue performance of warm mix-recycled asphalt mixture can be improved and the hot in-place recycling construction period in winter can be extended. The technology of warm mix-recycled modified asphalt SMA mixture has wide foreground.