Evaluation of Membrane Interlayers for Prevention of Crack Reflection in Thin Overlays

摘要

This report is the final report resulting from case studies of pavement performance conducted by the U. S. Army Engineer Waterways Experiment Station as requested by the U. S. Army Forces Command, Fort McPherson, Ga. The purpose of this study was to determine if a layer consisting of an asphalt-rubber membrane or a nonwoven fabric placed under a thin asphaltic concrete overlay (2 in. or less) will stop reflection cracking from occurring in the overlay. Field tests of two asphalt-rubber membrane formulations and three nonwoven fabrics were placed on roads and airfield pavements at five Army installations in various areas of the United States. The initial report covered the actual construction and performance of the materials for a period of 6 months after construction. This report covers the performance of the materials after a period of from 3 to 4 years, during which annual inspections were made. The results of the field tests indicate that in a cold environment the use of these membranes does not prevent or retard reflection cracking from occurring. The asphalt-rubber material was not evaluated over a long enough period of time in a warm climate to determine if reflection cracking was sufficiently prevented or retarded to warrant use of this material. (Author)