Research on High-RAP Asphalt Mixtures with Rejuvenators and WMA Additives

This study is to evaluate the mechanical and chemical properties of the asphalt concrete (AC) mixture, fine aggregate matrix (FAM), and binder modified by three different rejuvenators and warm mix asphalt (WMA) additive. In this regard, for testing of AC mixtures, the dynamic modulus, dynamic creep, and semicircular bending (SCB) fracture tests were conducted. For testing of FAM mixtures, three types of strain-controlled torsional oscillatory shear tests (i.e., strain sweep, frequency sweep, and time sweep) and the static creep-recovery tests were employed for comparative purposes. For binders, the Fourier transform infrared (FTIR) spectroscopy, saturates-aromatics-resins-asphaltenes (SARA) analysis, dynamic shear rheometer (DSR), and atomic force microscopy (AFM) were used to characterize the physicochemical and mechanical aspects of the asphalt binders. Based on test and analysis results, the rejuvenators can soften the materials, increase the rutting potential and may mitigate moisture damage resistance, while improving cracking and fatigue resistance of the asphaltic mixtures. A comparison between AC mixtures and corresponding FAM mixtures revealed the interrelationships between the two length scales. From the binder tests, it appears that the rejuvenators decrease either carbonyl or sulfoxide or both indices. Addition of rejuvenators to the mixture of recycled asphalt binder and virgin binder led to a decrease in the amount of asphaltenes. Furthermore, rejuvenators improved colloidal instability index (CII), which implies that the aged binder has become more stable due to rejuvenation. The AFM phase images of binders indicated that the softening effect of rejuvenators corresponds to the mechanical test results from DSR.

• Record URL:
  https://digitalcommons.unl.edu/ndor/146
• 
• Record URL:
  https://rosap.ntl.bts.gov/view/dot/31604
• Corporate Authors:

  University of Nebraska, Lincoln

  Department of Civil Engineering
  Whittier Research Center
  Lincoln, NE  United States  68588

  Mid-America Transportation Center

  University of Nebraska-Lincoln
  2200 Vine Street, PO Box 830851
  Lincoln, NE  United States  68583-0851

  Nebraska Department of Roads

  Lincoln, NE  United States  68509-4759

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590

  Federal Transit Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Haghshenas, Hamzeh
  • Nabizadeh, Hesamaddin
  • Kim, Yong-Rak
  • Santosh, Kommidi
• Publication Date: 2016-9-27

Language

• English

Media Info

• Media Type: Digital/other
• Edition: Final Report
• Features: Figures; Photos; References; Tables;
• Pagination: 76p

Subject/Index Terms

• TRT Terms: Additives; Asphalt mixtures; Bituminous binders; Cracking; Fine aggregates; Laboratory tests; Mechanical tests; Mix design; Moisture damage; Pavement performance; Reclaimed asphalt pavements; Warm mix paving mixtures
• Subject Areas: Design; Highways; Materials; Pavements;

Filing Info

• Accession Number: 01619053
• Record Type: Publication
• Report/Paper Numbers: SPR-P1(15) M016, 26-1121-4021-001
• Files: NTL, TRIS, ATRI, USDOT, STATEDOT
• Created Date: Dec 21 2016 11:28AM