An Algorithm to Estimate Rational Values of Phase Angles and Moduli of Asphalt Mixtures

Abubeker W. Ahmed ； Krishna Prapoorna Biligiri ； Hassan Hakim

《International Journal of Pavement Research and Technology》 6卷6期 (2013/10) Pp. 745-754

https://doi.org/10.6135/ijprt.org.tw/2013.6(6).745

並列摘要

The objective of this study was to develop and evaluate an algorithm based on Fast Fourier Transform (FFT) that can calculate rational values of phase angle (ø) and moduli of the variants of asphalt mixtures for the data obtained from the different frequency sweep tests. ø and moduli for ten different asphalt mixtures resulting in over 690 data points collected from both USA and Sweden were computed using FFT. Theoretical observations revealed that there were significant differences for ø between FFT and other methods to the order of 10-50%; however, there was no difference in moduli estimates for any mix and was independent of the test. Precisely, the FFT method produced rational ø for mixtures that deviate from conventional mixture properties. Furthermore, statistical comparisons corroborated the predicted ø estimates indicative of significant differences between the analysis techniques; but, the moduli were unaffected by the analysis methods. The study successfully illustrated the FFT technique, a user-friendly analytical procedure that can obviate the errors in the rational estimation of the acutely sensitive viscoelastic parameters.

並列關鍵字

Asphalt mix ； Fast Fourier Transform ； Frequency-sweep test ； Moduli ； Phase angle

參考文獻

Biligiri, K.P., Kaloush, K.E., and Uzan, J. (2010). Evaluation of asphalt mixtures' viscoelastic properties using phase angle relationships, International Journal of Pavement Engineering, 11(2), pp. 143-152.

Pellinen, T. and Crockford, B. (2003). Comparison of Analysis Techniques to Obtain Modulus and Phase Angle from Sinusoidal Test Data, 6th International RILEM Symposium on Mechanical Testing for Bituminous Materials, Zurich, Switzerland.

Gilbert, S. (2007). Computational Science and Engineering, Massachusetts Institute of Technology, Wellesley – Cambridge Press, Massachusetts, USA.

Kim, Y., Seo, Y., King, M., and Momen, M. (2004). Dynamic modulus testing of asphalt concrete in indirect tension mode, Transportation Research Record, No. 1891, pp. 163-173.

NCHRP (2004). Guide for Mechanistic – Empirical Design of New and Rehabilitated Pavement Structures, NCHRP 1-37A Final Report, NCHRP, Transportation Research Board, National Research Council, Washington, D.C., USA.