Variability of site geophysical exploration results using surface wave methods
DOI:
https://doi.org/10.21703/0718-2813.2024.35.2796Keywords:
Surface Waves Methods, Variability, Soil dynamicsAbstract
After the 2010 Maule earthquake (Mw 8.8) major changes were made in seismic regulations at the national level. One of the most interesting aspects was the change in the methodology for the soil classification in the NCh433 design standard. In summary, there was a transition from the use of soil strength parameters to soil dynamic parameters, such as the harmonic average of the shear wave velocity in the first 30 m of the subsoil (Vs30) and the predominant period (Tg), whose incorporation is under review. In this study, results from 4 teams exploring the same 6 sites using various sensors, geometries, and procedures are compared, all of them using Surface Wave Methods (MOS, for its initials in Spanish). It is concluded that, in general, the estimation of Vs30 and Tg are quite robust, but important variations are observed in the shear wave velocity profiles obtained. For that reason, it is necessary the comparison of these results with the stratigraphy. These results point to the limitations and potential of MOS to estimate the dynamic properties of sites.
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