The Illinois Department of Transportation (IDOT) spends $2 million annually on reflective crack control treatments; however, the cost-effectiveness of these treatments had not been reliably determined. A recent study evaluated the cost-effectiveness of IDOT reflective crack control System A, which consists of a nonwoven polypropylene paving fabric, placed either in strips longitudinally over lane-widening joints or over the entire pavement (area treatment). The study was limited to projects constructed originally as rigid pavements and subsequently rehabilitated with one or more bituminous overlays. Performance of 52 projects across Illinois was assessed through crack mapping and from distress and serviceability data in IDOT’s condition rating survey database. Comparisons of measured reflective cracking in treated and control sections revealed that System A retarded longitudinal reflective widening crack development, but it did not significantly retard transverse reflective cracking, which agrees with earlier studies. However, both strip and area applications of these fabric treatments appeared to improve overall pavement serviceability, and they were estimated to increase rehabilitation life spans by 1.1 and 3.6 years, respectively. Reduction in life-cycle costs was estimated to be 4.4 and 6.2 percent when placed in medium and large quantities, respectively, and to be at a break-even level for small quantities. However, life-cycle benefits were found to be statistically insignificant. Limited permeability testing of field cores taken on severely distressed transverse joints suggested that waterproofing benefits could exist even after crack reflection. This was consistent with the observation that, although serviceability was generally improved with area treatment, crack reflection was not retarded relative to untreated areas.
Influence of Cracks on the Lifetime of Semi-Rigid Pavements