Relationship Between Shear Wave Velocity and Piezocone Penetration Tests on the Brazilian Continental Margin

Abstract

A detailed characterization of the shear wave velocity profile is an essential tool in the resolution of a variety of seismological and geotechnical engineering problems. The main objective of this study is to present equations capable of providing reliable shear wave velocity profile estimations based on CPTu parameters. The results of a series of pioneering in-situ seismic piezocone penetration tests on the Brazilian continental margin are presented in this paper. A complete geological and geotechnical characterization of multiple sites was performed. Multiparameter and single parameter correlations were proposed between the measured shear wave velocity and the piezocone penetration test parameters. The suitability of the proposed correlations was evaluated by means of a statistical analysis and compared to the performance of previously published correlations using the test data parameters as input. The results show that the study was successful in presenting equations with superior performance for local soil conditions. Furthermore, this study yielded new reliable correlations that will benefit future projects in similar offshore environments.

Numerical modelling of the seismic response of gentle slopes in Southeastern Brazil

“…The static and dynamic geotechnical properties of the soil profiles that constitute the submarine slopes studied were characterized for the parametric numerical analysis. This was achieved using the undrained shear strength and shear wave velocity profiles obtained from previous studies on the continental slope of the Campos Basin (Borges et al, 2016;Borges et al, 2020b). Three soil profile thicknesses were defined in the parametric analyses: 20 m, 50 m, and 100 m to cover shallow and deep slope profiles (Fig.…”

“…The shear wave velocity profiles were obtained from a correlation based on CPTu parameters (Borges et al, 2020b). The equation used in this study was developed from in-situ seismic piezocone penetration tests on the Brazilian continental margin reaching up to 150 m depth and is expressed in terms of the effective vertical stress:…”

“…This paper presents the results of numerical simulations of the seismic behavior of gentle slopes in soft clays, representative of conditions of the offshore Campos Basin, in Southeastern Brazil. For the numerical models, the geotechnical characterization of the undrained shear strength and shear wave velocity profiles were defined based on previous studies aimed at evaluating the static stability of slopes on the continental slope of the Campos Basin (Borges et al, 2016;Borges et al, 2020b). The numerical analyses considered gentle slope geometries defined from interpretations of a digital elevation model of the Campos Basin.…”