*Refer to the following footnotes for strength designations. See the AASHTO guide referenced below for further details. †Marshall stability number. ‡Texas triaxial values. §Compressive strength, lb/in2 (1 lb/in2 6.895 10
3 MPa) Source: Interim Guide for Design of Pavement Structures, American Association of State Highway and Transportation Officials, Washington, D.C., 1972 (rev. 1981), with permission.