Benefit/cost analysis as it relates to service life of geosynthetics

August 1, 2020

On the surface, performing a benefit/cost (B/C) analysis is a straightforward process. However, ensuring that such an analysis is accurate and thorough is a much more nuanced task. In 2008, Bob Koerner laid out the procedure for geomembranes in Geosynthetic Research Institute (GRI) White Paper #12 “GS Selection Based on B/C Ratio.” This article expands …

GSI to host webinar on stabilization with nailed or anchored geosynthetics the Wednesday

June 22, 2020

The Geosynthetic Institute (GSI) will sponsor a webinar, “In-Situ Stabilization of Soil Slopes Using Nailed or Anchored Geosynthetics,” on June 24, from 11:30 a.m. to 1 p.m. EDT. Geosynthetic Materials Association (GMA) member companies and their employees receive discounted rates on all GSI webinar and short course registrations. The sliding of soil slopes in the …

Test method for determining leakage through imperfections in GMs of a composite liner system

June 1, 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 …

GSI issues request-for-proposals for graduate student fellowships

May 18, 2020

The Geosynthetic Institute (GSI) announces a worldwide request-for-proposals (RFP) focusing on innovative geosynthetics research and development projects. There will be several awards given, each for $5,000. Emphasis will be placed on relevant topics of interest and/or concern to the geosynthetics community. The proposals must be submitted in the following four-page format: Page 1 – Letter …

How does your geosynthetic react to changes in temperature?

April 1, 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 is 15 years old

February 1, 2020

By Robert M. Koerner The GMA Techline was initiated on Sept. 1, 2004, as a free worldwide answer center for questions involving any, or all, aspects of geosynthetics. There were no constraints put on the questioners, or on the answers that were provided by the Geosynthetic Institute (GSI). To date, 3,500 Q and As have …

A forty-year anniversary for the first hardbound book on geosynthetics

October 1, 2019

By Robert M. Koerner In the late 1970s, I regularly invited speakers to make presentations to my geotechnical engineering classes at Drexel University. Two of them were very memorable: Bill Ragen of Mirafi and Bill Witherow of Carlisle. Their respective topics were “filter fabrics” and “pond liners,” and in truth I didn’t associate them with …

Commentary on flood abatement using geosynthetics

August 1, 2019

By Robert M. and George R. Koerner On Sept. 8, 1900, a Category 4 hurricane struck Galveston, Texas, which is situated on the Gulf of Mexico about 8 feet (2.4 m) above sea level. The storm created a 15-foot (4.6-m) storm surge, killing 8,000 to 12,000 people and causing massive destruction. Subsequently, four actions were …

Reflections on sustainability with respect to geosynthetic materials

June 1, 2019

By Robert M. and George R. Koerner Listening to and reading the news, there seems to be regular criticism of all plastics insofar as concerns as to their post-use disposal in light of their exceedingly long lifetimes. Rarely, if ever, is the distinction made as to which plastics are really necessary to society and which …

MSE wall failures can be mitigated through the use of geotextile filters

April 1, 2019

For the past 17 years, the Geosynthetic Institute (GSI) has been accumulating data on failures of geosynthetic reinforced mechanically stabilized earth (MSE) retaining walls. We presently have 320 cases, of which 201 (63%) have been caused in whole or part by water within, or adjacent to, the reinforced soil zone. We sincerely hope that our …