BACKGROUND: Imaging systems are commonly used for conducting pavement evaluations.  AASHTO Standard Practice for Collecting Images of Pavement Surfaces for Distress Detection (AASHTO Designation: PP 68) addresses the collection of images.  However, there are no widely accepted methods for measuring the characteristics of pavement surface images (such as 2-dimensional optical images and 3-dimensional surface elevation images).  There are also no widely accepted AASHTO standard practices for the calibration, certification, and verification of such images.  Research was needed to identify the characteristics of surface images that are essential for pavement evaluation and develop methods for measuring these characteristics, and also to develop recommended standard practices for implementing these methods.  This information will help highway agencies better evaluate image data collection systems and improve the process of pavement condition evaluation.

OBJECTIVES: The objectives of this research were to (1) identify and develop methods for measuring the characteristics of surface images used for pavement evaluation and analysis; and (2) develop recommended standard practices for the calibration, certification, and verification of such images, for consideration and adoption by AASHTO.

STATUS:  Research is complete.  The final report is under review and will be published as NCHRP Research Report 1106: Measuring the Characteristics of Pavement Surface Images.