Download or read book Interpretation of Fwd Data when Pavement Layers are Not Intact written by Y. Richard Kim and published by . This book was released on 1999 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: When FWD tests are performed on broken or cracked pavements (of which information is crucial in making rehabilitation and overlay decisions), the multi-layered elastic theory-based backcalulation programs assume that the effect of these discontinuities in a cracked layer on deflection basins would be accounted for by the reduction of the elastic modulus for that layer. However, it has been concluded and confirmed by researchers and practitioners that the backcalculation algorithms based on the multi-layered elastic theory produce large variation in the algorithms based on the multi-layered elastic theory produce large variation in the 'effective' moduli of the cracked layers. Studies have also shown that significant errors in the backcalculated pavement moduli can accrue from performing a static analysis of what is inherently a dynamic test. Unfortunately, dynamic analysis usually involves complex calculations and requires significant computation time, thus making it impracticable for routine applications. This study presents a methology based on deflection basin parameters.