Seismic soil classification for tropical residual soils using non-destructive geophysical methods and SPT blow count correlations (#2149)

Authors

Pinzon-Atencio, Wenddy

Mogoruza, Rogelio

Velasquez, Yarisel

Agudo, Naicolette

Harris, Jose

Mojica, Alexis

Grajales-Saavedra, Francisco

Abstract

Earthquakes are responsible for a significant amount of money losses and death tolls. For this reason, their force is considered in civil engineering designs. The first method that implemented earthquake effects was descriptive structural design, later it was developed a performance-based seismic structural design methodology. The latter considers the dynamic properties of the soil. An important factor for appropriate implementation of this methodology is the seismic site classification. The site classification can be estimated with the help of destructive geotechnical tests, such as SPT, CPT, PMT; together with statistical correlations. However, it can also be determined by using non-destructive testing (i.e. geophysical testing). These estimations can be done obtaining the average shear-wave velocity in the upper 30m and the fundamental frequency of the soil. In this study a comparison between the results obtained from refraction microtremor (ReMi) and Horizontal-to Vertical Spectral Ratio (HVSR) geophysical tests against existing engineering correlations based on SPT tests was developed. The soils tested correspond to tropical residual soils, from Panama City. Results show that the ReMi and HVSR tests in combination accurately represent the properties of the soil. Also, this study identifies which correlations are best suited to be used in residual soils similar to the studied site.