Volume 38, Issue 6 (November 2010)
Coefficients of Thermal Expansion of Concrete with Different Coarse Aggregates–Texas Data
The first section of this paper summarizes the efforts of Texas Department of Transportation (TxDOT) to evaluate the coefficients of thermal expansion (COTEs) of a total of 93 concrete mixtures, of which the only difference is the coarse aggregate incorporated. The mean COTE value of siliceous gravel concrete is about 30 % higher than that of limestone concrete. The data in Texas shows that the upper 50 % COTE values of limestone concrete overlaps the lower 20 % COTE values of siliceous gravel concrete. The results strongly suggest that pre-qualification of coarse aggregate for typical paving concrete in aspect to COTE should be considered. A model by Emanuel and Hulsey is used to back calculate COTE of coarse aggregate. The second section of this article compares the COTE data set on existing pavement measured by Federal Highway Administration with those obtained at TxDOT concrete laboratory.