Volume 35, Issue 5 (September 2012)
Index Puncture Resistance of Geomembranes Using Various Protection Geosynthetics
The puncturing of geomembranes by stones is unfortunately not uncommon. In order to prevent its occurrence, various geosynthetics have been used as protection materials. Needle punched nonwoven geotextiles (of various unit weights), geonet drainage composites, and geosynthetic clay liners have been used, and all are evaluated in this laboratory puncture study. Results from three standardized puncture test methods (tapered, pin, and pyramid shaped end probes) are compared to one another. The results show that all geomembranes are susceptible to puncture, with increasing thickness providing some, but limited, improvement. Geotextiles clearly show improved puncture protection, and the improvement is in linear proportion to their increasing unit weights. Geonet drainage composites also show improvement essentially in proportion to the unit weights of the geotextiles affixed to the surfaces of the geonet core. Geosynthetic clay liners also provide protection, again in proportion to the unit weight of the associated geotextiles, particularly when the bentonite is hydrated.