生物油再生剂对温拌再生沥青混合料性能影响

付光辉¹，徐钦升²，张铭剑¹，芮照诚^2*，郑世瑞¹，狄恩州²，金钊¹

1.齐河恒晟公路工程有限责任公司，山东 德州  251120；2.山东省交通科学研究院，山东 济南  250102

摘要：为提高废旧沥青混合料（reclaimed asphalt pavement，RAP）的再生利用水平，降低热再生过程中回收沥青的二次老化，保证再生沥青混合料的路用性能，在70#基质沥青中掺加回收沥青、生物油再生剂和温拌剂制备温拌再生沥青胶结料，回收沥青与基质沥青的质量比分别为0、20%、40%、60%、80%，生物油再生剂的质量为回收沥青质量的10%，温拌剂的质量为基质沥青与回收沥青总质量的2%。通过旋转黏度试验、多应力蠕变恢复试验和线性振幅扫描试验，测量温拌再生沥青胶结料高、低温下的流动特性、抗变形能力和抗疲劳性能；制备不同AC-20型温拌再生沥青混合料，通过车辙试验、低温小梁试验、冻融劈裂试验和四点弯曲疲劳试验等，测量AC-20型温拌再生沥青混合料的高温性能、低温性能、水稳定性和疲劳寿命。试验结果表明：随回收沥青与基质沥青质量比的增大，温拌再生沥青胶结料的旋转黏度增大，剪切应变减小，蠕变恢复率增大，不可恢复蠕变柔量减小，剪切应力随剪切应变的增大而先增大后减小，峰值应力增大，疲劳寿命减小，对应变的敏感性降低，高温抗变形能力比未加入生物油再生剂的沥青胶结料略降，疲劳性能得到有效改善；随回收沥青与基质沥青质量比的增大，AC-20型温拌再生沥青混合料的动稳定度增大，车辙深度减小，弯曲劲度模量增大，破坏弯拉应变减小，冻融前后劈裂强度减小，冻融强度劈裂比减小，疲劳寿命减小，高温抗变形能力比未加入生物油再生剂的沥青混合料降低，低温抗变形能力、抗冻能力和抗疲劳能力显著提高。在回收沥青与基质沥青质量比大于60%时，AC-20型温拌再生沥青混合料的路用性能仍可达到普通热拌沥青混合料水平。

关键词：道路工程；温拌再生沥青混合料；生物油再生剂；高温性能；低温性能；疲劳寿命

Influence of bio-oil regenerant on the performance of warm-mixed reclaimed asphalt mixture

FU Guanghui¹, XU Qinsheng², ZHANG Mingjian¹, RUI Zhaocheng^2*, ZHENG Shirui¹, DI Enzhou², JIN Zhao¹

1. Qihe Hengsheng Highway Engineering Co., Ltd., Dezhou 251120, China;

2. Shandong Transportation Institute, Jinan 250102, China

Abstract: To improve the recycling level of reclaimed asphalt pavement (RAP), reduce the secondary aging of recovered asphalt during the thermal regeneration process, and ensure the road performance of recycled asphalt mixtures, a warm mix recycled asphalt binder is prepared by adding reclaimed asphalt, bio-oil regenerant, and warm mix agent to 70# matrix asphalt. The quality ratios of reclaimed asphalt to matrix asphalt are 0, 20%, 40%, 60%, and 80%, with the mass of the bio-oil regenerant being 10% of the reclaimed asphalt mass and the mass of the warm mix agent being 2% of the total mass of matrix asphalt and reclaimed asphalt. The flow characteristics, deformation resistance, and fatigue performance of the warm mix recycled asphalt binder are measured through rotational viscosity tests, multi-stress creep recovery tests, and linear amplitude sweep tests at high temperatures. Different AC-20 type warm mix recycled asphalt mixtures are prepared, and their high-temperature performance, low-temperature performance, water stability, and fatigue life are measured through rutting tests, low-temperature beam tests, freeze-thaw splitting tests, and four-point bending fatigue tests. The test results indicate: 1) As the quality ratio of reclaimed asphalt to matrix asphalt increased, the rotational viscosity of the warm mix recycled asphalt binder increases, shear strain decreases, creep recovery rate increases, non-recoverable creep compliance decreases, shear stress initially increases and then decreases with increasing shear strain, peak stress increases, and fatigue life decreases, with reduced sensitivity to strain; The high-temperature deformation resistance slightly decreases compared to the binder without the bio-oil regenerant, while the fatigue performance is effectively improved. 2) As the quality ratio of reclaimed asphalt to matrix asphalt increases, the dynamic stability of the AC-20 type warm mix recycled asphalt mixture increases, rut depth decreases, bending stiffness modulus increases, failure tensile strain decreases, splitting strength before and after freeze-thaw decreases, freeze-thaw strength splitting ratio decreases, and fatigue life decreases. The high-temperature deformation resistance is reduced compared to the mixture without the bio-oil regenerant, while the low-temperature deformation resistance, freeze resistance, and fatigue resistance are significantly improved. When the quality ratio of reclaimed asphalt to matrix asphalt exceeds 60%, the road performance of the AC-20 type warm mix recycled asphalt mixture can still reach the level of ordinary hot mix asphalt mixture.

Keywords: road engineering; warm-mixed reclaimed asphalt mixture; bio-oil regenerant; high-temperature performance; low-temperature performance; fatigue life