MPC Research Reports |
Title: | Variability of the IDEAL-CT Test for Pavement Cracking to Achieve a Balanced Asphalt Mix Design |
Authors: | Pedro Romero |
University: | University of Utah |
Publication Date: | Feb 2023 |
Report #: | MPC-23-492 |
Project #: | MPC-589 |
TRID #: | 01875825 |
Keywords: | asphalt mixtures, laboratory tests, pavement cracking, tension tests, test procedures |
This report describes the research efforts aimed at determining the repeatability of the IDEAL-CT test for use as part of the balanced asphalt mix design process. Three mixes in common production in northern Utah were investigated by three different labs experienced in performance testing. Within-lab and between-lab variability were studied as well as a number of factors likely to cause variability. Recommendations were developed for specimen preparation, minimum number of replicates, and how to discard outliers. Using properly trimmed results, it was found that the test could be repeated within a laboratory with a coefficient of variation (CV) of 15% and between laboratories within a CV value of 20%. Four replicates are recommended with the result farthest from the mean discarded. No correlation between a higher CT index and greater durability was identified in this study.
Romero, Pedro. Variability of the IDEAL-CT Test for Pavement Cracking to Achieve a Balanced Asphalt Mix Design, MPC-23-492. North Dakota State University - Upper Great Plains Transportation Institute, Fargo: Mountain-Plains Consortium, 2023.