Seasonal and Hourly Variation of Pavement Deflections Measured With The Falling Weight Deflectometer (FWD)

摘要

The objective of this research project was to evaluate and quantify the effect of seasonal variation in material properties on the deflections measured with the Falling Weght Deflectometer (PWD). The study was initiated to quantify the effects of moisture content of subgrade soil and pavement temperature on the structural response (FWD measured deflections) of the pavement.nSites were selected based on pavement type, subgrade soil type, average number of frost free days, and average annual precipitation. Seven sites were selected in the central half of the state, four in the northeast and three in southwest Kansas. The data collected from October 1993 to September 1994 at each site included deflections using a Dynatest 8000 FWD, pavement surface and air temp¬eratures while conducting FWD tests, monthly precipitation and average air temperature for five days preceding the FWD tests and moisture content in the subgrade using principles of time domain reflectometry (TDR).