Abstract
The flexible pavement design program used by the Texas Department of Transportation (TXDOT) for the past 20 years, FPS1 1 , uses the Stiffness Coefficient, based on Dynaflect deflections, to characterize pavement strength. The difficulty in calculating pavement stiffness coefficients in a multi-layer pavement structure is a major deficiency in that version of FPS. A new version of the flexible pavement design program, FPS19, converts FPS to a linear elastic system using elastic moduli for pavement layer characterization. The elastic moduli for the various layers are backcalculated from deflection measurements obtained with a nondestructive testing technique using the Falling Weight Deflectometer (FWD), This report describes an evaluation of FPS19 conducted to establish the reliability of the program. The evaluation consists of performing a sensitivity analysis of the program to various inputs, comparing results obtained with the program with results from other existing pavement design procedures, including FPS1 1 , Texas Flexible Pavement System (TFPS), American Association of State Highways and Transportation Officials (AASHTO), and Asphalt Institute (Al), and conducting case studies on two TXDOT projects,
Carmona, Gerardo M (1998). An evaluation of the flexible pavement design system FPS19. Master's thesis, Texas A&M University. Available electronically from
https : / /hdl .handle .net /1969 .1 /ETD -TAMU -1998 -THESIS -C37.