The GMA Techline

April 1, 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 …

Members Only  

Construction water flow dynamics of the leak detection layer

By Abigail Gilson-Beck and Larry Shilling The double-lined containment facility featuring a leak detection system (LDS) is the most accurate way of assessing leakage through a primary geomembrane (Bonaparte and Gross 1992). This type of system also represents the gold standard for environmental protection, since leakage through the primary liner is collected and removed so …

Members Only  

CSPE performance and history in long-term potable water storage applications

By Brian Fraser, Steven Roades, Mike Neal and Alex Gersch Chlorosulfonated polyethylene (CSPE) is a synthetic rubber-based material manufactured by a calendaring process into multiple layers and combines with a polyester reinforcement fabric for additional strength. Hypalon is a DuPont trademark for CSPE synthetic rubber (CSM) noted for its resistance to chemicals, temperature extremes and …

International Achievement Awards

Recognizing design excellence in geosynthetics The International Achievement Awards, sponsored by the Industrial Fabrics Association International (IFAI), recognize innovation, technical skill and design excellence in geosynthetic applications.  The awards are an annual competition promoting awareness of the specialty fabrics used in thousands of products and applications ranging in size and shape. For more than 70 …

The GMA Techline

February 1, 2020

Moderated by George R. Koerner and Y. “Grace” Hsuan DARCIAN PERMEABILITY Q: I am aware of the section in your book regarding geomembrane “permeability” and get from it that it aims to calculate an equivalent Darcian permeability using vapor diffusion via Fick’s law. Can one use the derived permeability then when calculating flow using Darcy’s …

U.S. Bank Stadium geosynthetic reinforced stress relief wall

Design, construction and fire damage mitigation By Nathan M. Lichty, Stephan M. Gale and Timothy P. Bendell Demolition of the Hubert H. Humphrey Metrodome stadium in Minneapolis, Minn., occurred in 2014 and subsequent construction of U.S. Bank Stadium (Figure 1), the home of the Minnesota Vikings and host of the 2018 Super Bowl, occurred between …

Erosion control using concrete-enhanced synthetic turf

By Bradford H. Cooley and Bryan Scholl Concrete-enhanced synthetic turf (CEST) is a hardened revetment system best described as a fiber-reinforced, flexible concrete liner. It consists of a high-friction, impermeable geomembrane layer overlain by an engineered synthetic turf, which is infilled with a 5,000 psi (3.45 × 107 Pa) high-strength cementitious mix. The turf fibers …

Premier Product Preview offers first look at new products and services

Here’s your first look at some of the new products and services that will be on the show floor at the Geosynthetics Conference 2020: CASE STUDIES in North Charleston, S.C., March 8–10. The 2020 show floor will bring together exhibitors covering the gamut of geosynthetic products and services, from geomembranes to electrical leak location testing, …

Overcoming expansive soils with Tensar’s TriAx Geogrid

November 13, 2019

Expansion: it’s a win for communities when roads reach out and connect people to business, resources and formerly rural areas. But another form of expansion—soil that expands when water is added and shrinks when it dries out—can thwart this progress by making it hard to economically build and maintain long-lasting roads. “Expansive soil” is in …

Reinforcing dunes and bluffs with geosynthetics

October 1, 2019

By Brian Maggi, Christopher D. P. Baxter, Aaron Bradshaw, Annette Grilli and Naser Al Naser The devastating effects of recent hurricanes and nor’easters highlight the need to improve the resilience of coastal communities. There is a trend toward implementing “soft” engineering solutions such as dunes reinforced with geotextile sand containers (GSCs) or coastal bluffs stabilized …