Article Article
Inversion of Air-Coupled Surface Wave Pavement Testing Data Based on Individual Receiver Spacing Approach

Air-coupled SASW (spectral analysis of surface wave) testing is a seismic technique for in situ evaluation of elastic moduli and layer thickness of layered systems, such as pavements and soils. It is an improvement over the conventional SASW testing with ground-coupled sensors in a way that leaky surface waves are detected by noncontact (i.e. air-coupled or microphones) sensors. Commonly, the average of the dispersion curves for different receiver spacings is used in the inversion process. However, there may be significant differences in the dispersion curves for a different spacing due to the interference of a number of body and surface waves radiated from the surface, and even direct acoustic waves. This study presents an inversion procedure for the air-coupled SASW testing on asphalt concrete (AC) pavements based on an individual receiver spacing approach. The inversion process itself is done using artificial neural networks (ANNs). The ANNs were trained by using several hundred synthetic dispersion curves for different receiver spacings developed from the numerical simulation of air-coupled SASW test. The inversion results of the recently developed ANNs models were compared with the models developed based on the average dispersion curves. The results point to significant improvements in the pavement modulus profile prediction.



  • Zhu, J., and Popovics, J., 2002, "Non-contact detection of surface waves in concrete using an air-coupled sensor", In Quantitative Nondestructive Evaluation (Vol. 615, No. 1, pp. 1261-1268). AIP Publishing.
  • Ryden, N., Lowe, M. J. S., and Cawley, P., 2009, "Non-contact surface wave testing of pavements using a rolling microphone array", Proceedings of the NDTCE, Nantes, France, 30.
  • Nazarian, S., and Stokoe, K. H., 1986, "In situ determination of elastic moduli of pavement systems by spectral analysis of surface waves method" (theoretical aspects).
  • Gucunski, N. (1994). "Detection of multi-course surface pavement layers by the SASW method", Nondestructive Testing of Pavements and Backcalculation of Moduli: Second Volume. ASTM International.
  • Joh, S. H. (1996). "Advances in the data interpretation technique for spectral-analysis-of-surface-wave (SASW) measurements" (Doctoral dissertation).
  • Hadidi, R., and Gucunski, N. (2003). "Inversion of SASW dispersion curve using numerical simulation", Symposium on the application of Geophysics to Engineering and Environmental Problems (pp. SUR-01). San Antonio, Texas: SAGEEP.
  • Orozco, M. C. (2004). "Inversion method for spectral analysis of surface waves (SASW)", Ph.D. Dissertation, Georgia Institute of Technology
  • Tarantola, A. (2005). "Inverse problem theory and methods for model parameter estimation". (Elsevier, New York, 1987).
  • Sheu, J.C., K.H. Stokoe, and J.M. Roesset. (1988)." Effect of Reflected Waves in SASW Testing of Pavements", Transportation Research Record 1196, TRB, National Research Council, Washington, D.C., pp. 51-61.
  • Lu, Y., Cao, Y., McDaniel, J. G., and Wang, M. L.(2015), " Fast Inversion of Air-Coupled Spectral Analysis of Surface Wave (SASW) Using in situ Particle Displacement", ISPRS International Journal of Geo-Information, 4(4), 2619-2637.
  • Hughes, T. J. (1987). "Finite element method- linear static and dynamic finite element analysis". Englewood Cliffs, NJ, USA.
  • Kim J.H., H.G. Kwak (2008)." Nondestructive evaluation of elastic properties of concrete using simulation of surface waves", Computer-aided Civil and Infrastructure Engineering, 23(8), 611-24.
  • Nazarian, S. (1984). "In situ determination of elastic moduli of soil deposits and pavement systems by spectral-analysis-of-surface-waves method", Ph.D. dissertation, University of Texas at Austin.
  • Nazarian, S., M.R. Baker, and K. Crain. (1993). "Development and Testing of a Seismic Pavement Analyzer". Report SHRP-H-375. Strategic Highway Research Program, National Research Council, Washington, D.C.
  • Karim, H.H. and H.A.N. Al-dami, (2012) "Non-destructive testing of concrete structures using GPR technique with an intermediate antennas frequency", Eng. & Tech. Journal, UOT, Vol.30, No. 14, pp 2678-2693, 2012.
  • Williams, T.P., and N. Gucunski. 1995,"Neural networks for backcalculation of moduli from SASW test", Journal of computing in civil engineering, 9(1), 1-8.



Usage Shares
Total Views
67 Page Views
Total Shares
0 Tweets
0 PDF Downloads
0 Facebook Shares
Total Usage