Influence of bio-oil regenerant on the performance of warm-mixed reclaimed asphalt mixture
FU Guanghui
XU Qinsheng
ZHANG Mingjian
RUI Zhaocheng
ZHENG Shirui
DI Enzhou
JIN Zhao
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 engineeringwarm-mixed reclaimed asphalt mixturebio-oil regeneranthigh-temperature performancelow-temperature performancefatigue life
Publication Date：2025-07-30
Online Publishing Date：2026-05-22(First online date of this platform, not the publication date of the document)
Pages：7( 52-58 )