Geosynthetic materials in reflective crack prevention.

Reflective cracking due to shrinkage and brittleness in asphalt pavements can seriously degrade an asphalt overlay before it is near the end of its design life. Geosynthetics have been used to impede the reflection of existing transverse cracking to the new overlay. The geosynthetics are intended to minimize the tension transferred to the overlay from the existing pavement. The Oregon Department of Transportation (ODOT) installed a test section consisting of 98 transverse cracks treated with five different geosynthetic types, 22 transverse cracks treated with crack filling only and a control section of 20 untreated transverse cracks. The test and control sections were monitored from 1999 to 2007. Each of the 140 test sites were revisited once each year to determine if the cracks had reflected, and if they had, measure their length and width. At the end of the study comparisons were made to determine if the geosynthetic materials were effective at controlling (by preventing or lessening the return of) reflective cracking.