Resistance to UV rays and to chemical agents are among the main requirements
The waterproofing of reservoirs, artificial lakes and channels requires an accurate choice of geomembranes according to varying conditions and requirements. Subject to movement and vibration, they can suffer from deterioration by UV rays by exposure to weather and chemical attack.
“Geomembranes are used to prevent the migration of fluids from one location to another and guarantee water-tightness over the years, even under adverse conditions, such as harsh environments and exposure to bad weather”, says Paulo Rocha, civil engineer and technical coordinator at Maccaferri Latin America in an interview with AECweb. He adds that geomembranes, also known as geosynthetic membranes, must be produced with high-density polyethylene (HDPE) with a carbon black additive, increasing resistance to chemical agents and sun rays.
According to Maccaferri’s technical coordinator, when lakes are used for wastewater storage it is imperative that the sealing elements are abrasion-resistant. He emphasizes the importance of UV resistance, since edges and joins tend to get exposed to the sun. “Even under adverse conditions, over the years, geomembranes should ensure water-tightness to prevent the risk of contamination,” he adds.
To preserve the performance of the geomembrane great care is required during installation. Maccaferri’s technical coordinator warns that tests and trials are needed in the field, during and after the application of geomembranes. In addition, the time of day that the geomembrane is installed should be considered so that the effects of thermal expansion can be evaluated and any effects mitigated.
To assist during installation, Paulo Rocha recommends reading the NBR 16.199/2013: Thermoplastic Geomembranes — Installation in Geotechnical and Environmental Sanitation Works. Published by the ABNT (the Brazilian Association for Technical Standards), he recommended the publication to anyone interested in projects, construction, management, and supervision of works involving the use of geomembranes.
Clients expect reliability in these installations to reduce the risks of contamination caused by a leak in the containment structure. Such solutions can be delivered by a skilled solution provider, quality products and a well managed installation.