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Report Details

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.

How to Cite

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.

NDSU Dept 2880P.O. Box 6050Fargo, ND 58108-6050