Application of wavelet theory to find correlation between readings of two deflection measuring devices

Traffic speed deflectometer (TSD) and falling weight deflectometer (FWD) are two different devices of measuring the deflection of pavements. The deflection readings are then used to assess the pavement structural condition. In comparison to FWD, TSD is a new technology that measures effect of pavement deflection at traffic speed. Comparing and finding co-relations between deflection values of the two devices are critical in validating the deflection readings of TSD which measures velocity of deflection at traffic speed and calculates pavement deflection. This paper presents the findings of research that compared the deflection readings measured by, FWD and TSD devices, on Queenslandrs road network. Using wavelet theory, deflection readings given by two devices are represented as wavelets and these wavelets are compared to determine correlation. Experiments show that higher correlation values are obtained for the deflection values recorded by the two devices on the selected trial sites.