GSI Webinar Focuses on Lifetime Prediction of Geosynthetics

By Robert Koerner – The Geosynthetic Institute (GSI) will hold its first webinar of 2014 on Wednesday, January 8, from 11:30 am – 1:00 pm (EST). This monthly webinar series is held every second Wednesday of a month. GSI members enjoy discounted attendance. The January 8 topic focuses on the lifetime prediction of geosynthetics, including both exposed and non-exposed materials.

A FREQUENT QUESTION
A most frequently asked question regarding all types of geosynthetics is, “How long will they last?” This webinar addresses the question from both exposed and nonexposed perspectives. It utilizes for incubation purposes laboratory ultraviolet fluorescent tube weathering devices to simulate exposed conditions. Fifteen geosynthetics are evaluated; six geomembranes, two geogrids, four turf reinforcement materials and three geotextiles. Each have been incubated at 80°C, 70°C and 60°C until halflife of strength retained and elongation retained have occurred. The data is then extrapolated down to 20°C for laboratory halflife values. The calculations then progress to using site-specific radiation to obtain the equivalent field life. Arizona conditions are illustrated although the procedure is applicable worldwide.
The nonexposed conditions are evaluated based solely on a high density polyethylene (HDPE) geomembrane and uses landfill incubation cells at four elevated temperatures. Using full depletion of antioxidants, induction time, and halflife at 20°C, the total lifetime is obtained. The approximate lifetime for this geomembrane is 440 years! Since the incubation times took 12 years, other nonexposed geosynthetics were not evaluated with the conclusion that the buried (nonexposed) situation is a moot point for most geosynthetics and their respective applications.
LEARN MORE and REGISTER
“Lifetime Predictions of Exposed and Nonexposed Geosynthetics”
8 January 2014
11:30 am – 1:00 pm (EST)
Dr. Robert M. Koerner, P.E., is Director Emeritus of the Geosynthetic Institute, www.geosynthetic-institute.org.