ABSTRACT
A frequency temperature correction model for Falling Weight Deflectometer (FWD) back-calculated modulus was developed with the consideration of FWD loading and pavement temperature effect. Indirect tensile dynamic modulus and FWD testing were conducted to determine laboratory and field dynamic modulus, respectively. Frequencies of 33 and 16 Hz were evaluated as suggested by other researchers as the FWD representative frequency. It was found that the reduced frequency at the specific depth represents the FWD frequency based on the back-calculated and laboratory measured modulus. In addition, mid depth temperatures were found to be the most suitable pavement temperature in representing FWD back-calculated modulus. A regression equation of frequency and temperature was developed as a function of shift factor, slope of master curve and frequency. The correction model was verified using several frequencies and temperatures. It was found that temperatures and frequencies that are closer to field condition give lesser modulus prediction error. The frequency temperature correction model was validated and compared with other correction models; it was found that the developed regression equation gives the least prediction error of 8.2%.
