Determination of Damage Development in Asphalt Concrete Using Small-Scale Accelerated Pavement Testing via Frequency Domain Analysis Approach

Abstract

To predict the pavement response correctly at any condition, the constitutive relation between stress and strain will require the use of a damaged modulus. Several asphalt concrete slabs constructed in the laboratory using vibratory roller compactor and instrumented with strain gauges and thermocouples were tested under the one-third scaled accelerated loading device called MMLS3. A frequency domain approach has been used to analyze the continuous strain data. The constitutive equation in time domain has been transformed to frequency domain using the Fourier transform technique, and the complex modulus values have been determined continuously during the loading. The results indicated that complex modulus is affected by the combined effect of loading and temperature. A general trend of reduction of complex modulus attributable to these factors has been observed in the study. The analysis results indicate that the frequency domain approach is an efficient and better way to handle large amount of data generated in long-term pavement studies and it can be used to determine the change in the complex modulus attributable to loading.