Resilient modulus and Youngs modulus are parameters increasingly used to fundamentally characterize the behavior of pavement materials both in the laboratory and in the field. The paper documents the small-strain modulus response of unbound aggregate base course materials to various moisture environments. It is shown that modulus is not constant, even when held at constant moisture, and that significant changes in modulus will occur with drying and wetting of the material. The response to drying and wetting cycles appears to be repeatable, and suggests that the underlying mechanism that controls the response is reversible. The behavior documented herein can have significant impact on use of modulus for pavement design and quality acceptance.
Abstract