Introducing a new pavement structural index based on measurements of falling weight deflectometer

Falling Weight Deflectometer (FWD) is the standard equipment for structural evaluation of pavements. FWD measures the maximum deflection for different time histories of loading at several radial distances from the load center. As a result, the FWD deflection basin is obtained. There have been efforts to describe the structural condition of the pavements based on the structural indices obtained from the deflection basin. As FWD measures deflections at discrete points, the traditional structural indices have considered the deflection basin as a linear spline, instead of realistically considering it as a continuous curve. In this study, different synthetic pavement structures are analyzed, and a Gaussian function is fitted to each deflection basin. A new structural index (called DSP) is introduced based on the peak of the first derivative of the fitted function. FWD field measurements showed that the DSP has a good consistency with two traditional structural indices in ranking the stiffness of different pavement sections. A relationship between the DSP and the characteristics of the pavement structure was then obtained and verified using field measurements.

کلیدواژه ها:

Deflection basin ، Falling Weight Deflectometer ، Structural evaluation ، Pavement management systems