Comparison Of The Falling Weight Deflectometer And The Dynaflect For Pavement Evaluation

A literature search was made for the purpose of comparing deflection measuring devices. The Dynaflect, Road Rater, and Falling Weight Deflectometer (FWD) ranked highest when compared, using the criteria of cost, operational characteristics, and suitability. Field testing proved the Dynaflect and FWD were nearly equal in overall ability except in operational speed. Here the Dynaflect was superior primarily due to the automated sensor placement. The correlation coefficients obtained showed good agreement between the deflections measured by the two devices on all pavements tested except overlaid CRCP. This study indicates that there may be pavements and conditions for which the Dynaflect does not provide useful information or where present methods of data interpretation do not appear to be adequate.