Puncture Protection of Geomembranes Part II: Experimental

Abstract

Geomembrane protection materials should be considered in design if geomembranes are to properly serve the role of barrier materials. The type, thickness and properties of the required protection material are in significant need of a rational design method. This series of three papers provides a design method for the inclusion of geomembrane protection materials, geotextiles in particular. Part I focuses on theory, this paper, Part II, focuses on experiments, and Part III focuses on design examples. In this paper, truncated cone and stone puncture test results for both short and long term durations are presented. A 1.5 mm thick high density polyethylene (HDPE) geomembrane, and various nonwoven needle punched geotextiles with varying masses per unit area made from virgin polyester and polypropylene continuous and staple fibers were tested. Using the results of this testing program, a design methodology was developed for calculating the required mass per unit area of a puncture protection material for a given factor of safety. Conversely, the design can be used to determine the unknown factor of safety for a given type of protection material.

Stab resistance of shear thickening fluid (STF)-treated fabrics

“…Leslie et al [12] present some simple measurements of needle puncture resistance of various protective medical glove fabrics. Koerner et al [13], Narejo et al [14], and Wilson-Fahmy et al [15] provide a series of papers on the measurement and analysis of the puncture of geotextiles, which was further addressed by Ghosh [16]. The geotextile testing methods employ a variety of probe geometries, to simulate various gravel and bed conditions, as well as combined puncture and hydrostatic loading, to simulate conditions for textiles that are submerged or in contact with saturated soils.…”

Ten year creep puncture study of HDPE geomembranes protected by needle-punched nonwoven geotextiles

“…While many theses and technical papers have been written using this experimental setup, a series of three papers captures the entire program Narejo et al, 1996;Koerner et al, 1996). The resulting design formula uses a conventional factor of safety as follows:…”

Deformations of a geosynthetic clay liner beneath a geomembrane wrinkle and coarse gravel

“…In Tests 3-5, 17-18 and 24 this layer consisted of a 1200 g/m 2 nonwoven needle-punched geotextile placed above the geomembrane. According to the puncture equation developed by Narejo et al (1996), a geotextile with mass per unit area of 1200 g/m 2 would be sufficient to protect the geomembrane against short-term puncture at 250 kPa. In Test 6, a 2000 g/m 2 nonwoven needle-punched geotextile was used.…”