LLDPE yield point
October 1st, 2023
Q: Can you tell me why my linear low-density polyethylene (LLDPE) is currently showing a yield point? In years past, we have not seen this happen. A: The yield point of HDPE is the first observation of zero slope measured on a stress-strain response curve. In most cases, this occurs between 12% and 19% […]
How to attach and terminate geomembranes on a concrete structure
June 15th, 2023
HDPE and LLDPE geomembranes are commonly utilized as barriers and covers in various containment facilities, including solid waste landfills, liquid containment areas, mining ponds, agriculture, and aquaculture ponds. The connection of geomembranes to concrete walls and ancillary structures, such as pipe penetrations or outlet structures under hydraulic pressure, plays a crucial role in ensuring proper […]
Aboveground storage tank liners for energy applications
June 1st, 2022
FIGURE 1 Wooden oil tank near Odessa, Texas. Photograph courtesy of the author Over the past 20 years, hydraulic fracking rules and regulations have become increasingly stringent, and oil and gas (O&G) producers have become progressively more concerned with environmental stewardship. Quality, factory-fabricated geomembrane liners for the aboveground storage tank (AST) market have become a […]
Methane gas geomembrane permeability
April 1st, 2022
Q: What is the least permeable geomembrane to methane gas? Regarding the permeability of geomembranes to methane gas, could you send me some technical guidelines? A: High-density polyethylene (HDPE) geomembranes are denser (more crystalline) than linear low-density polyethylene (LLDPE) geomembranes and less permeable. The water vapor, solvent and methane transmission (diffusion) of an HDPE barrier […]
Geosynthetics for Alaska landfill closure
February 23rd, 2022
Solmax provides a combination of geosynthetics for Alaska landfill closure project with multiple geotechnical challenges. Installation of geosynthetics at the Homer Solid Waste Facility landfill in Alaska. Photograph courtesy of Solmax Kenai Peninsula Borough in southern Alaska needed to complete phase two of a landfill-closure project at its Homer (Alaska) Solid Waste Facility. This involved […]
How to create a natural-looking pond with a geomembrane liner
September 27th, 2021
Constructing water pond with a geomembrane in Sweden. Photograph courtesy of BTL Liners Not all lining material is created equal. Although preshaped rigid liners exist, they are not normally what you would choose for your fish-stocking pond. No matter how small or large the pond you have in mind, your best option today is flexible […]
The GMA Techline
February 1st, 2021
Moderated by George R. Koerner BIOLOGICAL DEGRADATION OF PE AND PP Q: Can you please enlighten me on the biological degradation of polyolefin polyethylene (PE) and polypropylene (PP)? A: Within the various plant forms of biological life, i.e., bacteria, actinomycetes, fungi and algae, polymer degradation is essentially nonexistent due to high molecular weight of the common […]
The GMA Techline
April 1st, 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 […]
Panorama
April 1st, 2019
GMA honors U.S. senator as ‘leader of the year’ The Geosynthetic Materials Association (GMA) honored Sen. Sheldon Whitehouse, D–R.I., with the GMA Leader of the Year Award during the fall Lobby Day in Washington, D.C., on Nov. 14, 2018. “I’m honored to be recognized in this way by the Geosynthetic Materials Association,” Sen. Whitehouse said, […]
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 […]