text Washington, D.C National Academy of Sciences 1981 monographic iv, 44 p. : ill. ; 28 cm. Transportation Research Board, Commission on Sociotechnical Systems, National Research Council. Reports presented at the 60th annual meeting of the Transportation Research Board. 0 0 0 625_730000000000000_NAT MCE Pavements Soil mechanics 625.73 NAT 0309032695 (pbk.) :