This case study of rutting in an asphaltic concrete pavement makes recourse to trenching full width and full depth to expose and observe the entire cross section of the structure. Rutting occurred in the vicinity of Station 59+00 on US 23, 1.5 miles north of Louisa, during August and September 1983 when traffic was diverted onto newly constructed northbound lanes (without final surface and shouldering) while excavation into the hillside was completed for the southbound lanes. Earth movers crossed the northbound lanes going to and from a waste area. Coal trucks (Figures 1 and 2) slowed, stopped, and crept where rutting was greatest. Some rutting had occurred throughout
