The growing interest in mechanistic pavement design has spurred the development of test methods to determine the mechanical properties of pavement materials. Among others, the dynamic modulus of asphalt mixes is one of the primary parameters needed for pavement design. The Ministère des Transports du Québec (MTQ) has developed a test method for determining the dynamic modulus of asphalt mixes. The test method development is described, including a discussion of the choice of the direct tractioncompression test, the sample preparation methodology and the repeatability of the test. The dynamic modulus master curves of 15 asphalt mixes were determined in order to develop a database for the assessment of asphalt mixes and the design of pavements in Quebec. The asphalt mixes consist of combinations of three gradations of different maximum nominal sizes and the five binder types most widely used in Quebec. It is shown that the shape of the master curve depends on the binder type, while its intensity depends on the gradation and air void content of the sample. Generalized master curves, for which the prediction error represents the effect of gradation and air void content, were determined for the different binder types. These general models are consistent with data reported in the literature.
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