Evaluation of Interface Shear Strength between Geosynthetics Under Wet Condition

Laboratory Investigation of the Effects of Temperature and Moisture on Interface Shear Strength of Textured Geomembrane and Geosynthetic Clay Liner

“…Damage to the shearing material surfaces was considered the primary cause. Stark et al (1996) and Seo et al (2007) observed significant changes in NW GTs and T-GMs after shearing.…”

“…Daniel et al (1998) and Seo et al (2007) indicated the shear strength of bentonite decreased significantly from 0 to 50% moisture content, but the shear strength at a water content of 50% was approximately the same as that of fully hydrated bentonite.…”

“…Polishing of T-GM asperities (decrease in asperity height), especially under higher normal stresses, also contributed to post-peak strength loss (Stark et al 1996, Seo et al 2007). Limited data is available regarding investigation of the effects of temperature on structure of the shearing surfaces.…”

“…Investigation of internal shear strength of GCLs is not as critical, as the use of needle punched (NP) reinforced GCLs has resulted in internal shear strengths to be greater than interface shear strengths under the majority of investigated normal stresses (McCartney et al 2002, Zornberg and McCartney 2009, McCartney et al 2009a). Many researchers have investigated the shear resistance along geosynthetic interfaces, specifically between GCLs and geomembranes (e.g., Hewitt et al 1997, Triplett and Fox 2001, Seo et al 2007, Vukelic et al 2008, McCartney et al 2009a, Zornberg and McCartney 2009, and Chen et al 2010. The majority of GCL interface shear research reported uses a large scale direct shear device to determine the interface shear strengths between GCLs and geomembranes (Hewitt et al 1997, Triplett and Fox 2001, McCartney et al 2009a).…”

“…A 300 mm by 300 mm or larger specimen size has been commonly used with interface shear testing , Seo et al 2007, Chen et al 2010). Generally, the dimensions of one specimen are larger than the other so as one specimen displaces, the shearing area can remain equal throughout the test.…”