Predicting Moisture Induced Damage To Asphaltic Concrete

Virginia is one of seven state and federal agencies participating in a field evaluation of a stripping test method developed under NCHRP Project 4-8 (3), "Predicting Moisture- Induced Damage to Asphaltic Concrete." The test method is being used to evaluate the efficacy of the method in predicting the degree of stripping that will occur on a 1,000 ft. (300 m) test section constructed with an asphaltic concrete believed to have a tendency to strip. The degree of stripping of the pavement will be evaluated by visual observation of cores taken periodically and by pavement surveys. In the test method resilient modulus and indirect tensile tests are being performed on preconditioned and non-preconditioned specimens in predicting the potential stripping. The strength or stiffness loss resulting from vacuum saturation preconditioning is being used to indicate potential immediate stripping, and the strength or stiffness loss under a more severe accelerated preconditioning indicates potential stripping after a long period of time. The tests have predicted that stripping will occur over a long period rather than a short period. Tests on cores taken 12 months after construction have shown a minor amount of stripping.