The layered elastic and three-dimensional finite element methods as implemented in the FAARFIELD program allow a direct approach for overlay design. FAARFIELD calculates the thickness of overlay required to provide a 20-year life, which satisfies the layered elastic failure criteria for limiting stress or strain. The 20-year life thickness is defined as the design thickness. Report DOT-FAA-PM-87/19, Design of Overlays for Rigid Airport Pavements (see Appendix 4), describes the developed through an FAA-funded research effort design method for overlays of rigid pavement. Overlay pavements are grouped into four different types