Adaptation of the AASHO pavement design guides to Oklahoma highways

Abstract

Data are reported on physical properties of roadbed structural materials from in-place samples of most of the flexible state highways built in Oklahoma over an 11-year period. Associated traffic volumes, load history and climatic conditions, making a total of seven variables, are reported. These variables are compared to two sets of surface roughness, or serviceability measurements obtained by use of the CHLOE profilometer. It is shown that little significant correlation exists between changes in serviceability index as measured by the CHLOE, and the physical properties and traffic. Similar conclusions have been reached in other states. Of the parameters observed, it appears that road surface roughness is more sensitive to rainfall, traffic volume and road surface thickness than to quality or thickness of basement layers.