Testing wind-resistant geosynthetics
October 1st, 2020
By George R. Koerner As you can see by Figure 1, we are experiencing a new age of geosynthetics. Over the past 15 years, we have seen a propensity of polymeric materials left exposed to rather than covered from the environment. This is in large part due to the strides geosynthetic manufacturers and polymer formulators […]
Methods to estimate pressures and strains in pond geomembrane bubbles
August 1st, 2020
By Richard Thiel, Hesham Eldesouky and Richard Brachman FIGURE 1 Bubbles in pond with 60-mil (1.5-mm) HDPE geomembrane on verge of bursting This article provides an update, validation and improved approach for predicting the shape, pressure and strains that can occur in an exposed geomembrane bubble (aka “whale”) created by gas trapped below the geomembrane […]
The GMA Techline
August 1st, 2020
Seaming dissimilar geomembranes Q: I kindly request your technical support in the questions below: A nonpolyethylene geomembrane was used in phase 1 of the tailings dam waterproofing system of a gold mine. For the expansion (phase 2), the use of a high-density polyethylene (HDPE) geomembrane is being evaluated. How can the HDPE geomembrane join the bituminous […]
Assessment of condition of an uncovered geosynthetic landfill bottom liner system
June 1st, 2020
By James L. Hanson and Nazlı Yeşiller Composite liner systems consisting of geomembranes (GMs) placed over geosynthetic clay liners (GCLs) commonly are used for containment applications. Such systems are used in base liners for ponds, reservoirs, basins and canals, and bottom and cover liner systems for landfill facilities. Even though the use of GCL-GM composites […]
Test method for determining leakage through imperfections in GMs of a composite liner system
June 1st, 2020
George R. Koerner This article describes a large-scale test method intended to determine the leakage through imperfections in a geomembrane (GM) under a given head. It can be used as a performance test to simulate field conditions where the GM is physically breached. The test method places a GM test specimen of 2 feet (0.6 […]
Geomembrane wrinkles: Your challenges and solutions
May 11th, 2020
Wrinkles are all too common when installing a new geomembrane. Small wrinkles can turn into cracks under pressure. That, in turn, can compromise the integrity of an entire geomembrane installation and cause a costly amount of damage. In this article, we take a closer look at why geomembrane wrinkles form and how you can avoid […]
IGS North America to host webinar on electrical leak location
April 28th, 2020
The Geosynthetic Institute (GSI) will sponsor a webinar, “IGS Electrical Leak Location Seminar Series Ep. 4,” on May 14, from 12:00 p.m. to 1 p.m. CDT. The webinar will explain ASTM D8265: The new standard practice for covered geomembrane testing. The aim of the newly published standard practice for covered geomembrane electrical leak location testing […]
GSI to host webinar on wave management with geomembranes
April 6th, 2020
The Geosynthetic Institute (GSI) will sponsor a webinar, “Wave (or Wrinkle) Management for Proper Deployment of Geomembranes,” on April 15, from 11:30 a.m. to 1 p.m. EST. Geosynthetic Materials Association (GMA) member companies and their employees receive discounted rates on all GSI webinar and short course registrations. An intrinsic property of all exposed geomembranes is […]
How does your geosynthetic react to changes in temperature?
April 1st, 2020
An essential aspect of geosynthetics is that they function well over a large range of temperatures in either buried or exposed environments. There has been much work in this area; see Giroud and Morel (1992), Koerner and Koerner (1995 and 2006), Lord, Soong and Koerner (1995), and Tsuboi, Imaizumi and Miyaji (1998). Most of the […]
The GMA Techline
April 1st, 2020
Moderated by George R. Koerner and Y. “Grace” Hsuan Welding Rod Q: This question is in regard to the welding rod intended for welding of geomembranes (both high-density polyethylene [HDPE] and linear low-density polyethylene [LLDPE]). Are there any GRI GM13- or GM17-based requirements for welding rods or are there any white papers or specifications? I […]