Evaluation of Asphalt Mixtures Resistance to Cement-Treated Base Reflective Cracking in the Laboratory

Cement-treated base (CTB) is a mixture of aggregates and/or granular soils combined with a defined amount of Portland cement and water that hardens after compaction and curing to form a durable paving material. CTB is widely used as a pavement base for highways, parking lots, and airports, before paving the wearing (surface) course of asphalt or Portland cement concrete mixture to complete the pavement structure. The use of the correct quantity of Portland cement, adequate water, thorough mixing, and proper curing are all important factors to permit maximum compaction and prevent any cracking. If a CTB layer has cracks, they will most probably propagate as reflective cracking to the upper layer (i.e., asphalt mixture layer). Asphalt mixtures produced to be constructed over a CTB or a cracked base should be evaluated against reflective cracking for better performance during the pavement service life. There are varieties of laboratory tests that are used to simulate the propagation mechanism of reflective cracking in pavements – and each with limitations. In this project, the available laboratory tests will be evaluated, and a laboratory test setup will be considered and used to test an asphalt mixture layer on top of a simulated CTB layer at low and room temperatures. The considered test setup should properly simulate the propagation mechanism of reflective cracking in pavements. The aim is to examine if adding the CTB layer to the existing test will still give valid data and reasonable findings. The accomplishment of the project objective require the following tasks: (1) conducting an in-depth literature review, (2) a laboratory test setup will be selected and assessed to evaluate the effect of CTB reflective cracking on asphalt mixture layers on top of it, (3) preparation of Hot-Mix Asphalt (HMA) mixtures for testing, and (4) evaluation of reflective cracking resistance for lab-produced HMA mixtures on top of a CTB layer using the considered laboratory test setup at room temperature and low temperature.

Language

  • English

Project

  • Status: Active
  • Funding: $120000
  • Contract Numbers:

    19BLSU02

  • Sponsor Organizations:

    Office of the Assistant Secretary for Research and Technology

    University Transportation Centers Program
    Department of Transportation
    Washington, DC  United States  20590
  • Managing Organizations:

    Transportation Consortium of South-Central States

    Louisiana State University
    Baton Rouge, LA  United States  70803
  • Project Managers:

    Melson, Christopher

  • Performing Organizations:

    Louisiana State University and A&M College

    202 Himes Hall
    Baton Rouge, LA  United States  70803
  • Principal Investigators:

    Sadek, Husam

    Hassan, Marwa

    Berryman, Charles

  • Start Date: 20190815
  • Expected Completion Date: 20210215
  • Actual Completion Date: 0
  • USDOT Program: University Transportation Centers Program

Subject/Index Terms

Filing Info

  • Accession Number: 01713223
  • Record Type: Research project
  • Source Agency: Transportation Consortium of South-Central States
  • Contract Numbers: 19BLSU02
  • Files: UTC, RiP
  • Created Date: Aug 5 2019 4:20PM