为研究橡胶粉和低密度聚乙烯(LDPE)掺量对沥青混合料综合路用性能的影响,变化4种橡胶粉和LDPE掺量,采用弹性恢复率、针入度、软化点、177℃旋转黏度4种改性沥青的常规性能试验,利用车辙、低温弯曲和四分点加载控制应变疲劳试验,研究了橡胶粉和LDPE掺量对复合改性沥青及其混合料性能的影响规律。结果表明:以软化点≥60℃,25℃针入度25~60(0.1 mm),177℃旋转黏度1.5~4.5 Pa·s,25℃弹性恢复率≥65%作为判别标准优选了4种LDPE与橡胶粉复配方案,经室内试验和试验路验证推荐最佳复配方案为6%LDPE+18%橡胶粉。橡胶粉与LDPE复合改性沥青混合料具有优良的高温稳定性和抗疲劳耐久性,工程实践证明LDPE与橡胶粉复合改性沥青混凝土延长了道路的使用寿命,经济、社会效益显著。
in order to study the influence of rubber powder and low density polyethylene (LDPE) content on the comprehensive road performance of asphalt mixture, Change the dosage of 4 kinds of rubber powder and LDPE with elastic recovery, penetration, softening point, 177℃ viscosity four kinds of conventional t modified asphalt performance test methods, using rutting, low temperature bending and quartile strain fatigue test load control, dosage of rubber powder and LDPE was studied on the properties of composite modified asphalt and its mixture are studied, results show that the softening point or 60 ℃ , 25℃ penetration (0. 1 mm) , 25 -60℃ 177 ℃ rotary viscosity 1.5 -4.5 Pa· s, 25℃elastic recovery rate is 65% or higher as the judging standard of optimizing the four kinds of LDPE with rubber powder compound solution, verified by laboratory test and test road recommend the best distribution scheme for 6% LDPE + 18% rubber powder. Rubber powder/LDPE composite modified asphalt mixture has good high temperature stability and fatigue durability, engineering practice proved that LDPE composite modi- fied asphalt and rubber powder concrete extend the service life of the road, economic and social benefit is remarkable.