What is the Present Serviceability Index (PSI)?
The PSI is just a measure of the current overall rating of a section of highway based upon visual observation. The scale goes from 5 (perfect) to 0 (awful). It is similar to the 100 point rating scale used in our CAMP-RS program.
In pavement design, it is used to define the minimum acceptable level of quality. This terminal PSI allows an agency to define what is the anticipated PSI when a road is rebuilt or rehabilitated. New York State Department of Transportation uses a terminal PSI of 2 for lower volume state highways.
Present Serviceability Index