Abstract
A two-lane, dual-dual, 50mph, level, tangent roadway having a 1967 AADT of 68.000 vehicles with a high percentage of trucks was studied under uninterrupted flow conditions. A relationship between mixed volume and equivalent passenger car volume was determined for 20,40,60 and 80 percent truck groups. The passenger car equivalent of trucks was found to approach a value of two as the percent of trucks in the stream approached 180 percent. The relationship between cars and trucks was determined on the basis of equal speeds.