Stress Paths in Undrained Triaxial Tests with Anisotropic Consolidation on Marine Sediments of Southern Italy

Abstract

The present document is the first paper of a serial of studies ongoing in geotechnical laboratory testing and in situ testing of marine sediments in the southern Italy coastal area. For this first stage, Undrained triaxial compression tests with anisotropic consolidation (CK0U) have been performed on marine sediments collected in boreholes carried out in the seabed, in a depth of 8 m to 18 m below the seabed. The use of this compression test allows: (i) to consolidate the specimens, under the application of vertical load, limiting lateral strain and without reaching failure; (ii) the evaluate the entity of the maximum axial strain in the aforementioned conditions; (iii) to measure, during the entire cutting phase, the pore pressure values. The purpose of this paper is to highlight the first set of results from this particular triaxial compression test. The representation of the results by means of stress paths, allow to identify distinctly the breaking point of the specimens, defining with extreme precision the limit of the shear strength and cohesion of the soil without resorting to Mohr’s circles.

Keywords: Marine sediments, Undrained triaxial test, Anisotropic consolidation.