Minnesota Pollution Control Agency updates geosynthetic liner guidelines for stormwater management

August 30, 2018

The Minnesota Pollution Control Agency (Minnesota PCA) revised and released new geosynthetic liner guidelines for stormwater management in August. The guidelines specify where liners are required and where liners are recommended, liner specifications (e.g., HDPE, GCL, PVC), and how to select an appropriate liner. “Liners are designed to limit infiltration of water from a stormwater …

IGS releases new edition of the ‘Guide to the Specification of Geosynthetics’

August 9, 2018

The International Geosynthetics Society (IGS) has released the fifth edition of the “Guide to the Specification of Geosynthetics.” The objective of this document is to be a generic guide and aid to those writing geosynthetic specifications. The guide will provide information that is useful to those who use specifications, buyers of geosynthetics and installers. The …

New ASTM International standard will help in construction with GCLs

August 2, 2018

A newly released ASTM International standard will help those who construct and install geosynthetic clay liners (GCLs), which are used to help with containment for: landfills coal combustion residual storage cells mining operations remediation and environmental protection projects The new standard (D8204) focuses on evaluating both best practices as well as possible negative impacts of …

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Part 2: Field evaluation of the performance of unpaved roads incorporating geosynthetics—Planning

April 1, 2016

Introduction Scope and terminology The mechanisms that govern unpaved road performance are complex. Therefore, it is legitimate to try to get quantitative data from laboratory and field tests, but test interpretation can be correct only if there is a good understanding of the mechanisms (which was the purpose of the Part 1 article), rigorous planning …

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Part 1 Durability of geosynthetics: The basics

August 1, 2015

By John H. Greenwood Author’s note This article is based on a training presentation delivered on Sept. 24, 2014, at the 10th International Conference on Geosynthetics in Berlin, Germany. That talk was itself based on courses given at ERA Technology, Leatherhead, U.K., with Alan Friday, and later at SKZ in Würzburg, Germany, with the participation …

ASTM announces new geogrid standard

July 21, 2015

A new geogrid test method from the standards organization, ASTM International, has been issued, according to a July 20 ASTM press release. The release said that the test described in the standard—D7864/D7864M, Test Method for Determining the Aperture Stability Modulus of Geogrids—will help ensure that geogrids meet product specific calibrated and validated levels of aperture …

Gaining a better understanding of the porometer test (ASTM D6767)

June 1, 2015

By Bruce Lacina and Melissa Medlin 1. Introduction The ASTM international standard test method for pore size characteristics of geotextiles by capillary flow test provides a wealth of information about the physical makeup of the structure and pore spaces in a geotextile sample. This test is often referred to as the pore size distribution (PSD) …

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Recognizing the benefits of GRS bridge-building technology

August 1, 2012

Take the leap of faith By Jessica Bies Introduction More than seven years after the Federal Highway Administration (FHWA) and local officials in Defiance County, Ohio, built their first geosynthetic-reinforced soil (GRS) integrated bridge, county engineers throughout the U.S. are starting to recognize the benefits of using GRS bridge technology. Still promoting widespread application of …

The need for erosion control material specifications

February 1, 2012

By Bob & George Koerner The authors feel that a reasonable case can be made that generic specifications have significantly aided both geotextile materials (e.g., via AASHTO specs) and geomembrane materials (e.g., via GRI specs). Such specifications address most common situations and also provide a platform from which unusual or atypical site-specific conditions can be …

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HDPE & LLDPE rates

June 1, 2011

From the GMA Techline RE: HDPE & LLDPE rates I have always been under the impression that in using field tensiometers on jobsites that the rates for HDPE and LLDPE are different —HDPE at 2in./min. and LLDPE at 20in./min. However, I don’t have any documentation to back this up. Can you provide me with any …