热拌沥青混合料低温施工机理

Mechanism on Hot Mix Asphalt Construction under Low Temperature Condition

选用不同含量的添加剂ADZ、ADW、ADS分别加入SBS改性沥青和基质沥青中,测试其在110℃、120℃、135℃下的粘度和软化点。测定粘度,是为了探索低温施工的机理,不同含量添加剂的加入使沥青的粘度降低,从而实现沥青混凝土在较低温度下的施工。测定软化点,主要是评估添加剂的加入在实现降低摊铺或碾压温度的情况下是否会影响其路用高温性能。试验结果表明:3种添加剂均能在一定程度上降低基质沥青和SBS改性沥青的粘度。其中,在温度较低(120℃和110℃)时,ADW和ADS对SBS改性沥青、基质沥青的降粘效果较ADZ明显。基质沥青的软化点随着3种添加剂掺量的增加而增加。3种添加剂含量较低时,SBS改性沥青的软化点反而减小。

In order to explore the mechanism of low temperature construction and influence of additives on the high temperature performance of the asphalt concrete pavement, the viscosity at 110 ℃, 120 ℃ and 135 ℃ and softening point were measured for SBS modified asphalt and base asphalt with different additive content of ADZ, ADW or ADS, respectively. The additives can reduce viscosity of asphalt and realize construction of asphalt concrete in low temperature. The experimental results showed that： To some extent, three kinds of additives can reduce the viscosity of base asphalt or SBS modified bitumen. In contrast, at lower temperature （120℃ or 110 ℃）, the viscosity of SBS modified asphalt and base asphalt with ADW or ADS were obvious smaller than that of ADZ. With the increase of the three types of additive content, the softening points of base asphalt also increased. However, the softening points of SBS modified asphalt with lower additive content of ADZ, ADW or ADS were smaller than those without ADZ, ADW or ADS.