Evaluating Pavements and Selecting Solutions

Evaluating the existing pavement condition is an important part of the pavement preservation and rehabilitation process. A comprehensive evaluation provides valuable information about the pavement's condition, performance capabilities, and limitations including the following:

• Identification of all in-situ pavement layers

• Characteristics and behavior of in-place pavement materials

• Presence, type, and extent of distress

• Structural condition and load-carrying capacity

• Functional characteristics of the pavement, such as grades, roughness, friction, and noise

Several activities can be performed as a part of the pavement evaluation process (see Hall et al. 2001; Hoerner et al. 2001; NCHRP 2007). Specifics will vary from project to project, depending on the project type and relative significance. For the purpose of determining whether or not a concrete overlay is a good candidate for an overlay, the process can be divided into the following mandatory and optional steps. The steps for pavement evaluation are shown in Figures 7 and 8 on the following pages. Appendix A also provides evaluation tables based on existing pavement type and condition.

Mandatory evaluation activities include the following:

• Historical data collection, records review, and future projections (desk review)

• Visual examination (on-site review)

• Core analysis

• Pavement evaluation report

Optional evaluation activities include the following:

• Additional tests (including FWD, analyses of material-related distresses, drainage, roughness, and surface friction) if the cause of distress is unknown or if additional information is needed to determine the extent of distress

• Condition assessment profile

The evaluation concludes with a profile of the overall pavement condition assessment. See Figure 8.