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Amsterdam Schiphol Airport: Effective stormwater management

April 28, 2021

Changing climate conditions demanded a comprehensive project that protects Amsterdam’s airport from stormwater. The effects of climate change are noticeable on a global level. More extreme weather conditions require adaptations that issue a special challenge to high-risk construction and critical infrastructure components.  TenCate Geosynthetics joined forces with the Hydraulic Engineering Company, Syntraal and other local companies to develop and provide sophisticated climate-adaptive stormwater management solutions, called “Aquabase.” In the framework of a pilot project for …

Fabtech Australia replaces huge anaerobic lagoon geosynthetic cover

April 7, 2021

Goulburn Valley Water in Australia has undertaken upgrade work to the 266-million-gallon (50-megaliter) High Rate Anaerobic Lagoon (HRAL) located at their Daldy Road, Shepparton, Victoria, waste management facility. The lagoon has an area of 538,196 square feet (50,000 m2). The upgrade work includes removing the existing cover, which has reached the end of its service …

GMA Techline: Anchors, tie-rods and whalers

April 1, 2021

Q: We are having issues related to obstructions in the reinforced zone of our mechanically stabilized earth (MSE) retaining walls. In the first case, there is a rock outcrop that is limiting the length of the geogrid reinforcement. In the second case, we have a drop-down inlet structure to divert stormwater, which is in the …

GMA Techline: Geomembranes for reinforcement?

Q: We are using Robert Koerner’s Designing with Geosynthetics to calculate the required thickness of a geomembrane. See Figure 1 and Equation 1 from the book for details. Can you point us in the right direction with the mobilization distance, x? A: Yes, please see Figure 2 for high-density polyethylene (HDPE). It shows ASTM D6706 …

GMA Techline: Installing a geomembrane low to high gradient?

Q: We are a large liner installation firm that has been asked to install a geomembrane liner from low gradient to high gradient. Is this the new normal? A: This is not normal, and we suggest you strongly object to this recommendation. There are many stakeholders in regard to panel layout (i.e., installer, general contractor, …

Modular geosynthetics construction

By Edward J. Silva, T. D. Stark and Duff Simbeck Modular construction is a process in which a building or other item is constructed primarily off-site; under controlled factory conditions; and using the same design, materials, equipment, testing and construction quality control and assurance (CQC/CQA) techniques as a field-constructed facility—but usually in about one-half the …

GMA Techline: GRI-GM19 peel specification

Q: Our liner system is a double composite and along a western tie-in. We need to extrusion-weld the secondary 60-mil (1.5-mm) HDPE (new cell) to an existing secondary 40-mil (1-mm) HDPE (old cell), and the state is continuing to have issues with the fact that we are using the 40-mil (1-mm) GRI-GM19 peel specification as …

Development of a new design method for geosynthetic-reinforced RPEs

By Pietro Rimoldi and Nicola Brusa Rapid and extreme climate change is putting our planet under stress. As a consequence, in mountain and hilly regions, infrastructure and people are more often threatened by quick and unpredictable rockfall events. Falling boulders can have extremely high speeds, exceeding 11 mph (5 m/s) and up to 67 mph …

GMA Techline: Concrete interlayers

Q: We are interested in using a geotextile as an “unbonded concrete interlayer” over existing concrete pavement to float the new slab over deteriorated pavement, instead of a thin asphalt layer. Do you have any guidance for us in this regard? A: Over the past several years, 16-ounce-per-square-yard (542-g/m2) nonwoven needlepunched geotextiles have been used …

Comparative analysis of the flow and filtration capabilities of sediment retention devices—Part 2

By James E. Sprague and C. Joel Sprague Sediment retention devices (SRDs) include silt fences, wattles, filter logs, compost socks and various types of stormwater inlet protectors. They are a widely used best management practice (BMP) to provide sediment filtration from stormwater runoff while allowing water passage. However, SRD performance varies greatly in flow rate …