Document Type : Research Article
Abstract
The current study investigates the effects of recycled low-density polyethylene (R-LDPE) polymer and waste-paper fiber (w-PF) on the performance of the binder and stone matrix asphalt (SMA) mixtures. The effect of R-LDPE and W-PF was investigated individually and collectively on both the volumetric (bulk density, air voids, voids in mineral aggregate, and voids filled with asphalt) and mechanical properties (Marshall stability, flow and Marshall modulus). W-PF fibers were added to SMA mixtures in different ratios of 0.3 %, 0.5 %, and 0.7 %, while 3% of R-LDPE was added to improve asphalt mixture performance. The results showed that incorporating both R-LDPE and w-PF in asphalt binder has a positive effect on mixture performance, but with various levels. Collective modifiers have increased air voids, voids in mineral aggregate, Marshall stability and marshal modulus up to 15 %, 3%, 42% and 70%, respectively, at 3.3% MC (mix collective additives) in comparison to control SMA. The results also show a reduction in bulk density, voids filled with asphalt and flow to the level of 0.6%, 4% and 49%, respectively. This indicates that the use of waste and recycled materials, especially in the combined form offers a sustainable approach to stabilizing asphalt binder for SMA mixtures.