Strength Mobilisation in Karlsruhe Fine Sand

The strength mobilisation framework was adopted for the first time to describe the stress–strain responses for three different types of sands, including a total of 30 published drained triaxial tests—25 for Karlsruhe Fine Sand, 2 for Ottawa sands and 3 for Fontainebleau sand, under confining pressures ranging from 50 to 400 kPa. The peak shear strength τpeak obtained from drained triaxial shearing of these sands was used to normalise shear stress. Shear strains normalised at peak strength γpeak and at half peak of shear strength γM=2 were taken as the normalised reference strains, and the results were compared. Power–law functions were then derived when the mobilised strength was between 0.2τpeak and 0.8τpeak. Exponents of the power–law functions of these sands were found to be lower than in the published undrained shearing data of clays. Using γM=2 as the reference strain shows a slightly better power–law correlation than using γpeak. Linear relationships between the reference strains and variables, such as relative density, relative dilatancy index, and dilatancy, are identified.