Good gravel road maintenance or rehabilitation depends on two basic principles: proper use of a motorgrader (or other grading device) and use of good surface gravel. The use of the grader to properly shape the road is obvious to almost everyone, but the quality, volume, and size distribution of gravel needed is not as well understood. It seems that most gravel maintenance or rehabilitation problems are blamed on the grader operator when the actual problem is often material related. This is particularly true when dealing with the problem of corrugation or “washboarding” as it is often called in the field. This problem is often perceived as being caused by the grader, but it is primarily caused by the material itself. This manual provides information on what makes a good gravel road surface.
Copyright 2000; revised 2015