A comparative study on measured vs. Predicted pavement responses from falling weight deflectometer (FWD) measurements
- 312 Downloads
Falling weight deflectometer (FWD) drops were applied on the entire 24 test sections, and the resulting surface deflections were measured simultaneously using FWD geophones. The MODULUS 4.0 backcalculation program developed by the Texas Transportation Institute (TTI) was used to backcalculate the asphalt concrete layer moduli values of each test section. then the backcalculated moduli values were entered into a forward calculation program, WES-5, with known pavement layer thicknesses, assumed Poisson's ratio, and the magnitude and geometry of FWD loading to calculate the surface and depth deflections. The surface and depth deflections were used to calculate the average vertical strains of different layers at the centerline of loading. In the validation process, the comparisons between the measured and predicted pavement responses were made.
Keywordsbackcalculation falling weight deflectometer forward calculation pavement response validation
Unable to display preview. Download preview PDF.
- Hoffman, M.S. and Thompson, M.R. (1982). “A comparative study of selected nondestructive testing Devices.” TRR 852, Transportation Research Board, Washington D.C.Google Scholar
- Khosla, N.P. (1991).An evaluation of pavement instrumentation technology, Final Report, Research Project No. FHWA-EP-621-NC-01, Department of Civil Engineering, North Carolina State University.Google Scholar
- Khosla, N.P., Kim, Y.R., Satish, S., and Kim, N. (1992).A comparative study of performance of different designs for flexible pavements, Interim Report, Research Project No. 23241-87-1, Department of Civil Engineering, North Carolina State University.Google Scholar
- Kim, N. (1994).Development of performance prediction models for asphalt concrete layers, Ph.D. Dissertation, North Carolina State University.Google Scholar
- Ong, C.L., Newcomb, D.E., and Siddharthan, R. (1992).Comparison of dynamic and static backcalculation modulus for three layer pavements, Published in TRR, Transportation Research Board, Washington D.C.Google Scholar
- Stubstad, R.N., Khosla, N.P., and Wynn, W.W. (1989). “Construction of fully instrumented test pavements in north Carolina.” CRREL Symposium,Proc. on State of the Art of Pavement Response Monitoring Systems for Roads and Airfields, West Lebanon, N.H.Google Scholar
- Tholen, O., Sharma, J., and Terrel, R.L. (1985).Comparison of falling weight deflectometer with other deflection testing devices. TRR 1007, Transportation Research Board, Washington D.C.Google Scholar
- Ullidtz, P. (1987).Pavement Analysis. Elsvier, New York.Google Scholar
- Van Cauwelaert, F.J., Alexander, D.R., White, T.D., and Barker, W.R. (1989).Multilayer elastic program for backcalculating layer moduli in pavement evaluation. in nondestructive testing of pavements and backcalculation of moduli, Special Technical Publication 1026, American Society for Testing and Materials.Google Scholar