Geogrids, geonets and geomembranes

A typical uniaxial stress-strain behaviour of an HDPE geomembrane is also shown in Fig. 8.29. While maximum elongation is several hundred per cent, yield occurs at 10-15% strain. A safety factor of 1.5-2.5 is usually taken into account when employing geomembranes, which brings any allowable strain down to 5-6.5%. Geomembranes are viscoelastic materials and their stress-strain behaviour is time dependent, so over the long term, applied stresses could lead to their creep failure. 

29 (a)Textured geomembrane and (b) stress-strain behaviour of HOPE geomembrane. 

30 Creep characteristic of geomembranes (a) schematic behaviour of geomembrane under constant load at prolong periods, and (b) notched constant load test on HOPE geomembrane (immersed in solution of 10% IGPAU90% tap water). 

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Common name for all kinds of synthetic materials including geotextiles, geomembranes, geonets, geogrids, and so forth, used in geotechnical and civil engineering applications. 

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