Measuring pavement surface deflections using a falling weight deflectometer(FWD)is a common technique to assess structural conditions and guide pavement maintenance decisions.However,FWD deflections in flexible paveme...Measuring pavement surface deflections using a falling weight deflectometer(FWD)is a common technique to assess structural conditions and guide pavement maintenance decisions.However,FWD deflections in flexible pavements are highly sensitive to temperature variations due to the viscoelastic nature of asphalt.An accurate analysis of these deflections requires adequate correction to a reference temperature,typically using the method outlined in the AASHTO 1993 design guide.Despite its widespread use,the specific input asphalt temperature for this correction is not well-defined.In this study,temperature sensors were installed at various depths in three full-depth asphalt pavement sections in Indiana(USA),allowing for the measurement of temperature gradients during FWD tests conducted at different times throughout the day.The study evaluated the accuracy of deflection corrections when using different temperature correction factors,calculated using measured temperatures at various depths following the AASHTO 1993 guidelines.The results demonstrate that using the pavement temperature at 100 mm depth provided more accurate deflection corrections than using surface or mid-depth temperatures in full-depth asphalt pavements.展开更多
Pavement surface deflections collected from falling weight deflectometer(FWD)tests are widely used to estimate in-service pavement structural conditions and aid in pavement management systems.However,asphalt pavement ...Pavement surface deflections collected from falling weight deflectometer(FWD)tests are widely used to estimate in-service pavement structural conditions and aid in pavement management systems.However,asphalt pavement deflections are affected by variations in temperature due to the viscoelastic nature of asphalt.This study evaluated the temperature effects on field FWD deflections performed at two different temperatures on the same day on three Indiana full-depth asphalt pavement sections.A parametric study was performed using a finite element(FE)model validated by field FWD data.Three different subgrade conditions and seven temperature gradients were simulated using the FE model.Field-and model-based FWD deflections were used to evaluate the accuracy of the AASTHO 1993 temperature correction method.It was found that the AASHTO 1993 method may be insufficient to fully consider the temperature effects on FWD deflections.In addition to temperature changes,the deflection level was found to be a major parameter in the variation of FWD deflections.Higher deflection levels showed higher deflection variation and lower AASHTO 1993 correction method accuracy.展开更多
基金supported in part by the Joint Transportation Research Program administered by the Indiana Department of Transportation and Purdue University.
文摘Measuring pavement surface deflections using a falling weight deflectometer(FWD)is a common technique to assess structural conditions and guide pavement maintenance decisions.However,FWD deflections in flexible pavements are highly sensitive to temperature variations due to the viscoelastic nature of asphalt.An accurate analysis of these deflections requires adequate correction to a reference temperature,typically using the method outlined in the AASHTO 1993 design guide.Despite its widespread use,the specific input asphalt temperature for this correction is not well-defined.In this study,temperature sensors were installed at various depths in three full-depth asphalt pavement sections in Indiana(USA),allowing for the measurement of temperature gradients during FWD tests conducted at different times throughout the day.The study evaluated the accuracy of deflection corrections when using different temperature correction factors,calculated using measured temperatures at various depths following the AASHTO 1993 guidelines.The results demonstrate that using the pavement temperature at 100 mm depth provided more accurate deflection corrections than using surface or mid-depth temperatures in full-depth asphalt pavements.
文摘Pavement surface deflections collected from falling weight deflectometer(FWD)tests are widely used to estimate in-service pavement structural conditions and aid in pavement management systems.However,asphalt pavement deflections are affected by variations in temperature due to the viscoelastic nature of asphalt.This study evaluated the temperature effects on field FWD deflections performed at two different temperatures on the same day on three Indiana full-depth asphalt pavement sections.A parametric study was performed using a finite element(FE)model validated by field FWD data.Three different subgrade conditions and seven temperature gradients were simulated using the FE model.Field-and model-based FWD deflections were used to evaluate the accuracy of the AASTHO 1993 temperature correction method.It was found that the AASHTO 1993 method may be insufficient to fully consider the temperature effects on FWD deflections.In addition to temperature changes,the deflection level was found to be a major parameter in the variation of FWD deflections.Higher deflection levels showed higher deflection variation and lower AASHTO 1993 correction method accuracy.
