Geotechnical characterization of igneous saprolite using the Seismic Cone Penetration Test (SCPTu) from a jungle site in South America

This paper summarizes and discusses the results from Seismic Cone Penetration Tests (SCPTu) on a 40 m thick, igneous, saprolite horizon at a jungle site in South America. These results are compared against the results from conventional geotechnical drilling with in-situ tests (e.g., Standard Penetration Tests (SPT) and down-hole Vane Shear Tests (VST), and laboratory testing results. Saprolite is formed in situ by chemical weathering of the parent rock, resulting in soils with significant microstructure. This is evaluated under the framework of the Soil Behaviour Type (SBT) and the Modified Normalized Small-strain Rigidity Index, K*G. A discussion of the main limitations of conventional SCPTu classification and empirical correlation methods, when applied to saprolite, is presented in this paper along with a framework for interpretation and classification of this material, using information from the drilling and laboratory testing programs.

Sanchez-Marrou, J., H. Barriga-Gallarday and I. Berru-García. 2019. “Geotechnical characterization of igneous saprolite using the Seismic Cone Penetration Test (SCPTu) from a jungle site in South America,” in Proceedings of GeoStJohns, Under Land & Sea: 72nd Canadian Geotechnical Conference, St. John’s, Newfoundland, September 29 – October 2, 2019. St. John’s, NL: Canadian Geotechnical Society.