The GMA Techline
August 1st, 2019
Moderated by Robert M. Koerner, George R. Koerner and Y. “Grace” Hsuan A geotextile for unpaved driveway/road? Q: Is there any point in using a 150 g/m2 (4.4 oz/yd2) nonwoven geotextile in building an unpaved gravel driveway or gravel road? If so, what should be the most important characteristics of the fabric and what are […]
The GMA Techline
June 1st, 2019
Who is doing the testing? Q: This question relates to the number of rolls to be selected as the lot sample for specification conformance testing and refers to ASTM D4354. When I look at this standard, it appears the values in Table 1 of GRI’s White Paper #10 refer to the number of units to […]
The GMA Techline
April 1st, 2019
Vegetation causing gases under geomembrane? Q: I have a site where we are installing a high-density polyethylene (HDPE) liner in an existing pond. Because of some residual heavy metals in the top layer of soil, I would like to strip off the top 3–6 inches (7.6–15.2 cm) of soil and vegetation. Alternatively, we could mow and […]
The GMA Techline
February 1st, 2019
Geomembranes for canal lining Q: Our company is an international member of the Industrial Fabrics Association International (IFAI). Our government is planning to line their water canals with a geomembrane to prevent water seepage into the soil. We have been approached by many to suggest the most suitable material with specifications to guide them in […]
The GMA Techline
October 1st, 2018
Toxicity of nonwovens? Q: Are there any comprehensive tests (or a general synopsis) of the environmental toxicity of leachate from nonwoven polypropylene fabrics when aged in a freshwater or saltwater solution? Regulatory and municipal bodies in Europe and New Zealand are requesting more info about products that are used in riparian and coastal environments. A: […]
The GMA Techline answers all
August 1st, 2018
UV Weathering of Geotextiles Q: My firm is providing construction quality assurance services for a landfill cell expansion. We are having an issue with our contractor and are going to be in a position of having 8 ounces/square yard (271 g/m2) of nonwoven geotextile exposed for a period of time, which exceeds the seven-day limit […]