Digital Imaging for Screening and Making Measurement of Features on Highway Rock Cuts


Highway rock cuts must be maintained for the safety of the motoring public. Since highways cover vast areas through differing geological terrains, it is not cost effective to remediate all rock cuts; remediation efforts have to be prioritized. Even doing traditional geological engineering evaluations on all the rock cuts is prohibitive.

Most jurisdictions now use a rock mass classification such as the Oregon Rock Hazard Rating System (RHRS) to streamline the process by quickly classifying rock cuts, rather than evaluating each in detail. The cuts that have the worst score in the classification can then be further evaluated in the traditional way.

This paper demonstrates how further efficiencies can be realized, by using computer scaled video images. Digital video image of entire highways can be acquired at highway speeds. Later using a computer, engineers can review the video, select areas that look like they may be problematic, and plan further investigations at those sites. Additionally, some of the parameters required in the classification systems, such as slope heights and slope angles can be measured directly on the digital images.

A low cost, state-of-the-art system developed to perform these tasks is described here. Typical measurement can be made with errors of less than 10%, which is more than adequate for the purposes of rock mass classification, and estimating rock quantities.

Meeting Name

Transportation Research Board, 82th Annual Meeting (2003: Jan. 12-16, Washington, DC)


Geosciences and Geological and Petroleum Engineering


University of Missouri Research Board

Keywords and Phrases

Computer Scaled Video Images; Digital Video Image; Highway Rock Cuts; Rock Mass Classification

Document Type

Article - Conference proceedings

Document Version


File Type





© 2003 Transportation Research Board, All rights reserved.

Publication Date

01 Jan 2003