旧料特性对热再生沥青混合料压实性能的影响研究

为了研究热再生沥青混合料的压实特性,采用旋转压实试验,通过对2种类型再生料的密实曲线计算所得的斜率K1和K2、压实能量指数CEI、交通密实指数TDI1和TDI2分析各旧料在不同加热温度和掺量下对再生料压实特性的影响。结果表明:1)旧料加热温度升高能提升旧沥青与新沥青的融合,可增加再生料中沥青的粘度,但并非旧料加热温度越高再生料越容易压实,在100℃、120℃和140℃三种温度条件下,120℃掺加旧料的再生料更易压实;2)旧料掺量越大,再生料越难压实,但使用过程中其抗变形能力越好;3)AC-20普通沥青再生混合料更易压实,但抗变形能力明显不如AC-13改性沥青再生混合料。

Study on Influence of RAP Characteristics on the Compactability of Hot Recycled Asphalt Mixture

To study the compactability of hot recycled asphalt mixture,according to the compaction curve from gyration compaction test of two kinds of recycled asphalt mixture,the slop(K1 and K2),compaction energy index(CEI)and the traffic densification index(TDI1、TDI2)were calculated to analyze the influence of heating temperature and content of reclaimed asphalt pavement(RAP)on the compactability of recycled asphalt mixture.The results show that:1)The increase of RAP heating temperature promotes bending of aged bitumen and virgin bitumen,which can increase the bitumen viscosity of recycled mixture,but increasing the heating temperature of RAP cannot always improve the compactability of the recycled mixture.Under the three temperatures of 100℃,120℃and 140℃,the recycled hot mix asphalt concrete with 120℃RAP is easier to compact.2)Increasing RAP content will increase the difficulty in mixture compaction,but improve the anti-deformation ability.3)The AC-20 recycled mixtures with nonmodified bitumen is easier to compact than the AC-13 recycled mixtures with modified bitumen,but has worse anti-deformation ability.