SASW evaluation of asphaltic and cement concrete pavements using different heights of fall for a spherical mass

Abstract

A number of spectral analysis of surface wave tests were performed on asphaltic and cement concrete pavements by dropping freely a 6.5 kg spherical mass, having a radius of 5.82 cm, from a height (h) of 0.5–1.5 m. The maximum wavelength (λ_max), up to which the shear wave velocity profile can be detected with the usage of surface wave measurements, increases continuously with an increase in h. As compared to the asphaltic pavement, the values of λ_max and λ_min become greater for the chosen cement concrete pavement, where λ_min refers to the minimum wavelength. With h = 0.5 m, a good assessment of the top layers of both the present chosen asphaltic and the cement concrete pavements, including soil subgrade, can be made. For a given h, as compared to the selected asphaltic pavement, the first receiver in case of the chosen cement concrete pavement needs to be placed at a greater distance from the source. Inverse analysis has also been performed to characterise the shear wave velocity profile of different layers of the pavements.

Keywords:

• flexible pavements
• non-destructive testing
• rigid pavements
• spectral analysis of surface wave
• wave propagation

Acknowledgements

The financial support provided by Ministry of Shipping, Road Transport and Highways, New Delhi, India, under the research scheme ‘Testing of pavements using seismic waves’ is gratefully acknowledged.