Heap Leach Dump ― Granular Material and Geomembrane Interface Characterization

摘要

In order to evaluate the stability of a 110-meter high heap leach dump, built on a slope with a 5% mean steepness, which will be subjected to a secondary leaching process, it was necessary to determine the mechanical properties of the interfaces constituted by the foundation, a geomembrane and the dumped materials. A test program was developed aimed to evaluate the shear strength of interfaces constituted by granular materials with smooth and rough PVC, LLDPE, VFPE, VLDP, and HDPE geomembranes of different thickness, in addition to geomembrane/geotextile composites. Large scale direct shear tests were performed using 0.3x0.3m~2, 0.45x0.45m~2, and 0.6x0.6m~2 test specimens with interfaces that reproduced the type of materials, density, and level of stresses found on site. The material deposited is a crushed sandy gravel, with maximum grain size of 50.8 mm (2 inch).