Quantification of Pavement Rut Depth Using Stereovision Technology

Abstract

An attempt to investigate the potential capabilities and accuracy of the PC-based stereovision system in quantification of pavement rut depth was performed. This process was demonstrated using three rutted sections of flexible pavement. Selected highway pavement sections were chosen, using representative criteria that assured randomness in the studied parameters, for semiautomatic rut depth quantification. Surface measurements were represented by two-dimensional and three-dimensional plots, as well as contour maps for the rutted areas. Results obtained by this technique were compared with those obtained by the manual conventional method using a straightedge to check accuracy. Comparison with the manual (conventional) method showed that stereovision using dual charged-coupled device cameras mounted on a stand on a moving vehicle has a consistent potential accuracy of about one pixel (i.e., about 1.5 cm) on average in measuring the rut depth for the three sections. This result was compatible with the human operator's ability to point to the conjugate image points, which has a potential accuracy of about one to two pixels. Advantages of using the stereovision technique to quantify rut depth include remoteness, safety, and real-time potential due to the use of digital images.