Concrete dams | Concrete evidence
IWP&DC learns more about a waterproofing solution for concrete structures and the use of eco cement for concrete dams
Above: Fly ash concrete was used at the Hungry Horse Dam in Montana, US
CONSTRUCTED IN 1932, the Sheppard-Myers Dam in Pennsylvania, US is responsible for about 20% of the local water supply, and was in much need of rehabilitation as no significant work had taken place since the 1930s. Fortunately it was recently completed in May 2023 as, without it, the Pennsylvania Department of Environmental Protection could have mandated complete decommissioning of the facility. This US$10.84 million rehabilitation project comprised construction of a new, larger concrete labyrinth spillway with added capacity to accommodate current government standards for a maximum flood event, and rehabilitation of the downstream face of the dam, including the installation of a subsurface drainage system. Project engineers Gannett Fleming needed a permanent waterproofing solution for the new concrete structures, and encouraged by similar projects across the Mid-Atlantic region where Penetron Admix SB had been used, chose this as the waterproofing solution for the Sheppard-Myers Dam upgrade.
Reference
Getting to grips with eco cement by Libby Snow. 26 July 2022.
https://global.lockton.com/gb/ en/news-insights/getting-to- grips-with-eco-cement
Described as a crystalline concrete waterproofing admixture, Penetron Admix SB was used to treat concrete for the new auxiliary spillway and weir walls. Once added to concrete, the chemicals in the mixture create a catalytic reaction to generate a non-soluble crystalline formation throughout the pores and capillary tracts of concrete. These crystals permanently self-heal and seal micro-cracks, pores, and capillaries against the penetration of water (or liquids) from any direction – making the concrete impermeable. “The dam’s new concrete structures are now
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impermeable to water, even under the constant hydrostatic pressure typical of a water storage facility like the Sheppard-Myers Dam,” says Christopher Chen, Director of The Penetron Group. “The ability of Penetron Admix SB to permanently self-heal any future microcracks will also mitigate concrete deterioration over the service life of the concrete.” The product has also been used to help waterproof
concrete on a new weir that forms part of the Northeast Mississippi Regional Water Supply District’s recently completed US$1.2 million water supply expansion and upgrade project. The largest supplier of treated surface water in the
region, the district draws its water from the Tombigbee River basin, which drains northeastern Mississippi and parts of western Alabama. A major feature in the basin is the Tennessee-Tombigbee (Tenn-Tom) Waterway, which joins the Tennessee River and parts of the original Tombigbee River through dams and man- made canals, to serve as a navigation route between the Gulf of Mexico and the central United States. “The project included construction of a new weir for
the water treatment plant facility, as well as extensive repair and renovation work on the existing weir structures,” adds Christopher Chen, Director of The Penetron Group. B&B Concrete supplied the ready-mix concrete for the work, while structural engineers at Cook Coggin Engineers chose Penetron Admix SB as the waterproofing solution for the concrete walls of the new weir.
Other applications for the waterproofing admixture include protecting concrete structures from toxic
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