Ruggedness Study on the AASHTO T 336 Coefficient of Thermal Expansion of Concrete Test Method

A ruggedness study on the AASHTO T 336 coefficient of thermal expansion of concrete test method was performed to evaluate the factors most likely to affect the test results. Seven factors were evaluated: time at temperature extremes, water level, position of the linear variable differential transformer, number of segments, saturation criterion, specimen length, and temperature of the first segment. Two concrete mixtures were used in this study, four laboratories participated, and five commercially made coefficient of thermal expansion devices from two manufacturers were used. On the basis of the results obtained, saturation criterion was found to be the most significant factor. The other factors were found not to have a significant impact on the test results, have already been addressed in the most current version of the test method, or, in the authors’ opinion, do not warrant being addressed.