Physical and hydraulic response of geomembrane wrinkles underlying saturated fine tailings

The effect of applied pressure on the deformation of a prescribed wrinkle, with and without a hole, in four different geomembranes (1 and 2 mm thick high density polyethylene (HDPE) and 1 and 2 mm thick linear low-density polyethylene (LLDPE)), placed on a compacted silty-sand underliner and backfilled with saturated fine tailings at 65% solids content, is investigated. For the 1 mm thick geomembranes without holes, the gap beneath the wrinkle was eliminated (but the geomembrane was excessively strained) at an applied total stress of 250 kPa, whereas for the 2 mm thick geomembranes the gap remained even under a total stress of 1000 kPa. The short-term performance was the same for both LLDPE and HDPE. For wrinkles with a hole, any gap that remained beneath the wrinkle was completely filled by tailings. The tailings migrated into the gap beneath the wrinkle partly as free-flowing slurry and partly under the applied hydraulic gradient. There was a difference in the shape of the final wrinkle depending on whe...