Internal stability of crushed sands: experimental study

The current paper documents an experimental study conducted to evaluate the internal stability of sands subjected to seepage at high stresses. A custom-made one-dimensional compression cell with fluid flow capabilities was used to load and flush saturated specimens composed of selected sands with heterogeneous mineral composition. The degree of internal stability (i.e. the extent to which a soil can retain its mobile particles) was quantified with both the size distribution curves and the relative amounts of fragments collected in the effluent. Results indicate that: (a) uniform internally stable sands become internally unstable at high stresses, albeit temporarily; and (b) internal instability features are dependent on mineral composition and the extent of particle breakage. Particle-level force analyses suggest that the internal stability of crushed sands is dependent on the hydrodynamic conditions imposed.