含有高再生沥青路面与橡胶粉添加剂的沥青混合料混合物表征
As the price of petroleum and material costs escalate and pressures of maintaining the sustainability of our environment, owners must continually find methods to decrease material costs and maximize their benefits. This paper presents the findings of laboratory characterization of HMA mixtures containing high reclaimed asphalt pavement (RAP) content with crumb rubber (CR) additives. Five mixtures were examined in this study. The conventional mixture contained a styrene-butadiene-styrene, polymer-modified asphalt cement, Performance Grade (PG) 76-22M and no RAP. The second mixture utilized 15 percent RAP and PG 76-22M asphalt cement binder. The third mixture contains no RAP, 30 mesh CR additives blended (wet process) with a PG 64-22 binder. The fourth mixture contains 40 percent RAP, 30 mesh CR additives blended (dry process) with a PG 64-22 asphalt cement binder. The final mixture utilized 100 percent RAP with CR additives. Laboratory mixture characterization includes the Asphalt Mixture Performance Tests (Dynamic Modulus, E*, and Flow Number, FN), Semi-Circular Bend test, Dissipated Creep Strain Energy test, and the Modified Lottman test. In addition, Loaded Wheel Tracking, LWT, test was performed. Results indicate that the addition of CR additives as a dry feed to carry rejuvenating agents is promising. Mixtures containing high RAP content and CR additives exhibited similar performance as conventional mixture with PG 76-22M binder.