Mechanical Response of Lightly Cemented Sands under Different Orientations of the Principal Stress Axes

Abstract

This paper presents the results of an experimental program aiming to explore the mechanical response of lightly cemented sands under different orientations of the principal stress axes using the hollow cylinder torsional apparatus. Two compositions of lightly cemented sands featuring the same porosity/volumetric cement content index, η/Civ, but characterized by different cement content and sand density have been subjected to linear probing stress paths with orientations of the principal stress, ασ, varying from 0° to 90° from the vertical specimen axis. All the tests have been carried out under drained conditions. It will be shown that despite the same value of η/Civ, different soil strengths were recorded for the two cemented soil compositions. This may suggest that the relative contribution of the cementation and soil density may be affected by the orientation of principal stress axis during loading. The suitability of multiaxial strength criteria proposed for sand materials to reproduce the peak deviatoric strength of the lightly cemented sands is also investigated.