An Introduction to Evaluating Pavement Distress for Professional Engineers

The detrimental effects of traffic loading and environmental factors degrade all pavements. The deterioration manifests in a variety of ways (such as cracking, rutting, raveling, spalling), that reduce the structural integrity and functional quality of the pavement. Loss of structural integrity translates into a loss of load-carrying capacity. Loss of functional quality (increased roughness, decreased friction and surface drainage, foreign object damage (FOD) potential) compromises safety and reduces comfort of operation. Although the manner and speed with which pavements deteriorate differs, the overall trend is one in which the pavement condition changes from good to poor and the pavement surface condition progresses from smooth to rough, as illustrated in Figure 2-1. Factors governing changes in pavement condition include (ARRA, 2015): - Pavement type - Quality of project design - Quality of original construction, including mixes and materials - Type, thickness, and properties (strength, stiffness, durability, etc.) of individual pavement layers - Subgrade soil type, bearing properties, and moisture content - Traffic composition and loading characteristics - Environmental conditions - Types, levels, and effectiveness of maintenance activities