Permeability of compacted colliery spoil—a parametric study

摘要

Parametric studies were undertaken into the keyfactors affecting the hydraulic conductivity of a South Walescolliery spoil i.e.moulding moisture content, material properties,comparative effort, and confining stress. The studies were carriedout in the context of the construction of a colliery spoil landfillliner. The mounding moisture content of the compacted collieryspoil was found to give the lowest permeability at approximately1% wetter than optimum, a trend similar to that reported forcompacted clays, while increased comparative effort led toreduced permeability. The particle size distribution fromweathered samples of the spoil was typically found to be close tothe idealised Fuller's curve, with sufficient fines to generate anadequately low permeability; adjusting the maximum particle size(up to 50 mm) was not found to produce large variations inpermeability. Finally, confining stress was found to have asignificant impact on permeability particularly at low stress levels.