Subsurface Drainage and Premature Distresses in Concrete Pavement

Field and laboratory forensic investigations were used to identify the failure mechanism of a jointed plain concrete pavement with a subsurface drainage system in Virginia. Similar to many states' practice, this subsurface drainage system consists of open-graded drainage layer and edge drains to provide positive drainage for the pavement. The investigation included a review of construction practices and pavement performance records, a visual distress survey, nondestructive testing using a falling weight deflectometer, roughness measurements using a profiler, coring and boring for materials testing, observation wells, subgrade soil classification, mineralogy, determination of concrete compressive strength, edge drain camera inspection, and slab removal. On the basis of the investigation, it was concluded that lack of positive drainage along with heavily loaded truck traffic resulted in premature failure. The water entering the pavement because of poor joint sealing was trapped in the open-graded drainage layer; this led to severe faulting, midslab cracks, pumping, and eventual failure of the pavement.