Technical Summary
Durable Recycled Superpave
Mixes in Kansas
Report Number: K-TRAN: KSU-14-6 ▪ Publication Date: April 2018
Ye Gao
Shuvo Islam
Mustaque Hossain, Ph.D., P.E.
Kansas State University Transportation Center
Introduction
The use of economical and environment-friendly recycled asphalt materials
has become increasingly popular for asphalt pavement construction. In
general, reclaimed asphalt pavement (RAP) and recycled asphalt shingles
(RAS) are used in hot-mix asphalt (HMA). However, as higher amounts
of RAP/RAS material are being promoted, the potential for premature
pavement distresses, especially cracking, is increasing.
Setups for Indirect Tensile Strength
Test (left) and Semicircular
Bending Test (right)
Project Description
In this research, four recycled Superpave mixtures (SR) obtained from Kansas Department of
Transportation (KDOT) projects with varying RAP and RAS contents have been evaluated. Two
of these mixtures contained 10% RAP and 5% RAS, while the other two contained 25% RAP but
no RAS. Illinois semicircular bending (IL-SCB) and Florida indirect tensile strength (FL-IDT)
tests were performed to assess mixture cracking and fracture properties.
Project Results
These test results showed that mixtures containing 10% RAP and 5% RAS have relatively low
fracture energy (FE) and flexibility index (FI) but higher resilient modulus. However, creep
compliance and energy ratio (ER) of these mixtures are lower. These results indicate that mixtures
containing 10% RAP and 5% RAS are stiffer, more prone to cracking, and tend to absorb less
fracture energy. Mixtures with 25% RAP and no RAS showed the opposite behavior.
Project Information
For information on this report, please contact Mustaque Hossain, Ph.D., P.E.; Kansas State
University, 2124 Fiedler Hall, Manhattan, KS 66506; (785) 532-1576 phone;
[email protected].
Directions for Downloading
the Full Report
1
To download the full report, visit http://kdotapp.
ksdot.org/kdotlib/kdotlib2.aspx and do the
following:
1. Enter K-TRAN: KSU-14-6 in the search box.
. Click the Search button to the right of the
search box.
3. You may have to scroll to find the specific
report.
4. To download the report, click on the title of
the report to open the PDF file and save it
to your hard drive.
If you have any questions, please email us at KDOT#
[email protected].
KDOT reSearch
Page
Shuvo Islam