Materials-related distress (MRD) is a concern in the State of Michigan, affecting all concrete transportation structures including pavements, bridges, retaining walls, barriers, and abutments. MRDs are a direct result of a component breakdown within the concrete matrix as a result of the interaction between the concrete and the environment in which it serves. This is in contrast to distress (for example fatigue cracking or transverse cracks) that is primarily a result of traffic or poor construction practices, although it is noted that once a MRD related distress has manifested, it is possible that traffic may exacerbate the rate of deterioration of that distress. For example, "D" cracking occurs at joints due to the break down of the aggregate structure under influence of freeze-thaw cycles and can be attributed to poor aggregates, may develop spalls under repetitive traffic loading resulting in functional failure and poor ride quality. Because of this interaction between materials, traffic, and construction, it is difficult at times to attribute failures to one cause or another without a thorough examination of the mechanisms at work. This has resulted in an ongoing debate within the State regarding the role of MRD versus load-related distress in pavement failure. As such, the material characteristics of the portland cement concrete (PCC) must be directly considered when determining the relative contribution of MRD to the observed pavement distress.

The specific MRD mechanism and extent varies with location due to differences in local environmental factors, concrete constituent materials, construction practices, deicer applications, and traffic. MRD can occur even in properly constructed PCC pavement having adequate structural capacity, resulting in costly, premature concrete deterioration and failure. Thus it is essential to gain a better understanding of the extent of the problem within the State. If, as suspected, the majority of surface distress results from inherent material deficiencies, appropriate action should be taken to eliminate the cause or reduce it’s occurrence to a minimal level.

The general focus of this proposed research project is to (i) establish the extent of MRD affecting the total state network of concrete pavements (ii) identify projects (through the PMS database and field visits) that are subjected to MRD, (iii) analyze and diagnose the various MRDs common to Michigan, and (iv) provide recommendations to prevent future occurrences of MRD and suggested repairs or treatments, if feasible for existing pavements with MRD.