Mechanistic Design Concepts for Full-Depth Asphalt Concrete Pavements

摘要

A mechanistic design procedure for Full-Depth asphalt concrete AC pavements for highways is proposed and validated. The procedure is based on ILLI-PAVE, a stress dependent finite element computer program, coupled with appropriate transfer functions. Two material design criteria are considered: AC flexural fatigue cracking and subgrade rutting. Fatigue cracking is controlled by limiting the tensile strain at the bottom of the AC layer. Subgrade rutting is controlled by limiting the stress-ratio at the AC-subgrade interface. Algorithms were developed relating pavement response parameters (stresses, strains, deflections) to AC thickness, AC moduli, and subgrade moduli. The proposed mechanistic design procedure requires AC thicknesses less than those required by IDOT, The Asphalt Institute, and the Shell procedures. The thickness discrepancies vary depending on traffic and subgrade support.