Variability of Fiber Reinforcement, Peel Strength, and Internal Shear Strength in Needle-Punched GCLs

The objective of this study was to evaluate variability in reinforcement fibers, peel strength, and internal shear strength of needle-punched reinforced geosynthetic clay liners (GCLs). A methodology was proposed to characterize the reinforcement fibers via the number of reinforcement fiber bundles per specimen length, number of monofilament fibers per fiber bundle, and fiber diameter. Variability in reinforcement fibers was evaluated for six GCLs using the proposed methodology. Peel strength and internal direct shear tests were performed on a single GCL to assess the effect of reinforcement fiber variability on shear strength. No pattern was observed in the spatial variability of peel strength along the machine or cross-machine directions. However, peak internal shear strength correlated with manufacturer reported peel strength, and this correlation improved when peel strength was computed from specimens located adjacent and in machine direction relative to direct shear specimens.