Implementation of Low Temperature Test for Asphalt Mixtures to Improve the Longevity of Road Surfaces
http://www.mountain-plains.org/research/projects/downloads/2012_mpc_391.pdf
Record Type: UTC

Asphalt concrete pavements make up over 90% of the transportation network’s surface. Recent demands for increased use of environmentally sustainable materials have resulted in mixtures with different additives, including Recycled Asphalt Pavement (RAP) and Recycled Asphalt Shingles (RAS). However, for these materials to be truly sustainable, they must provide some long-term benefit or, at the very least, not be detrimental to the performance of the asphalt mixture. To deal with this issue the Utah Department of Transportation (UDOT) has been implementing the use of mechanical tests such as the Hamburg Wheel Tracking Device (WTD) to screen asphalt mixtures that might not have adequate high-temperature performance due to either mixture instability or incompatibility between components. The implementation of the Hamburg WTD as a screening test has significantly benefited the high temperature performance of asphalt pavements. However, it has not addressed the low and intermediate temperature performance reflected as thermal and fatigue cracking. Premature pavement failures have been observed that can be directly linked to inadequate intermediate and low temperature properties resulting in millions of dollars in maintenance cost. This proposal seeks to address this problem by developing a set of performance tests and specification to address the intermediate and low temperature properties of asphalt mixtures. A significant effort was undertaken during the past years to measure low temperature properties of asphalt mixtures by using the Bending Beam Rheometer (BBR) to test small beams made out of asphalt concrete (http://www2.udot.utah.gov/main/uconowner.gf?n=4493029359845211). While the work showed how the device can successfully be used in a laboratory environment, analysis of field samples are needed to develop the required specification limits and establish a balance between the high and the low temperature properties of asphalt mixtures thus ensuring longer lasting, cost effective, sustainable pavements no matter what additives are used. Research Objectives: The objectives of this study are to gather field data to select specification limits for the low temperature properties of asphalt mixtures placed on Utah roads (and possibly the Mountain West region). Specifically, it proposes to accomplish the following objectives: (1) Characterize low temperature properties of asphalt concrete field materials used in Utah during the duration of the study.(2) Establish a relation between laboratory design and field properties of hot mix asphalt. (3) Study the effect of recycled materials (RAP or RAS) on the low temperature properties of these asphalt mixtures. (4) Develop a specification limit to balance the high and low temperature properties of the asphalt mixtures currently being placed on the roads.
Start date: 2012/7/1
End date: 2013/6/30
Status: Active
Contract/Grant Number: DTRT12-G-UTC08
Secondary Number: MPC-391
Total Dollars: 31515
Source Organization: Mountain-Plains Consortium (MPC)
Date Added: 05/09/2012
Index Terms: Asphalt pavements, Low temperature, Service life, Hamburg Wheel Tracking Device, Bending beam tests, Asphalt mixtures, Recycled asphalt pavements, Asphalt shingles, Utah, Testing,

Federal Highway Administration
http://www.fhwa.dot.gov/
1200 New Jersey Avenue, SE
Washington, DC 20590
USA
Phone: (202) 366-4000

Kline, Robin
Phone: (202) 366-2732
Email: robin.kline@dot.gov

University of Utah, Salt Lake City
College of Engineering, Department of Civil Engineering
Salt Lake City, UT 84112-0561
USA

Romero, Pedro
Phone: (801) 587-7725
Fax: (801) 585-5477
Email: romero@civil.utah.edu