Using Pavement Distress Data to Assess Impact of Construction on Pavement Performance

Most state highway agencies specify incentives, disincentives, or acceptance criteria based on one or more attributes that can be measured during or immediately after construction (smoothness, early completion of construction, and nuclear density). In many scenarios in which contractors were awarded incentives, the pavement showed premature distress after construction. Furthermore, the magnitude of the incentive or disincentive is typically determined on the basis of intuition and past practice, without assessing the effect of the incentive’s attribute on pavement performance. In a study sponsored by the Michigan Department of Transportation (MDOT) and conducted by the Pavement Research Center of Excellence at Michigan State University, the impact of segregation on pavement performance was assessed, and an expedient test to detect segregation was developed so that MDOT could establish incentives, disincentives, or acceptance criteria. The study included 17 segregated pavement projects and 2 nonsegregated projects. Two types of segregation-related distress were observed: raveling, which was observed on 11 projects, and cracking, which was observed on 7 projects. Three projects showed both raveling and cracking. For each project, the raveled areas and the length of the cracks were measured over time, and their rates of growth were assessed. On the basis of the results, the reductions in the pavement service life due to raveling and cracking were estimated. It is shown that areas with heavy and medium degrees of segregation experience on average 73 and 56 percent reduction in pavement service life, respectively, due to raveling and 46 percent due to segregation-related cracks.