ABSTRACT
Coupled physical and hydraulic experiments are conducted to quantify leakage through circular geomembrane holes with diameters of 10 mm, 20 mm, and 50 mm. Three different tailings, fine-grained tailings with fines content of 90 % and d 10 of 1 μm (denoted as T1), silty sand tailings with fines content of 30 % and d 10 of 20 μm (denoted as T2), silty sand tailings with fines content of 20 % and d 10 of 40 μm (denoted as T3), are examined. The effective stress and pore pressure in the tailings above geomembrane and remote from the hole are ~170 kPa and ~350 kPa, respectively. It is shown that leakage through geomembrane hole is proportional to the hole radius (and not the area) for each type of tailings, and highly dependent on the fines content of the tailings. For example, the leakage for T2 and T3 tailings are 1.8-fold and 65-fold greater than that for the T1 tailings, respectively, for a given hole size. The practical implications are discussed.
