The Brayton Point Power Plant, New England's largest fossil-fueled generating facility, flushes 1.3 billion gallons of water a day into Mount Hope Bay. That’s the equivalent of 20 football field-sized swimming pools filled to a depth of 150 feet.
Environmental activists have warned for years that warming the waters of the bay has a negative effect on fish populations. The Brayton Point Cooling Towers are two natural draft cooling towers designed to reduce the amount of heated water that discharges into the bay by up to 95 percent. Each cooling tower will be 500 feet tall and will be about 360 feet wide at the bottom with concrete walls 20 inches thick.
The cooling tower’s varying shape required a flexible formwork system that could easily be configured to the changing diameters of the tower. The SK 175 self climbing cooling tower formwork system adjusts the dimensions of the hyperbolic concrete shape to meet this geometry. The system consists of adjustable steel formwork panels connected to a fully mechanized automatic climbing system that is anchored to the previously cast concrete ring of the tower. Each element is designed to be electromechanically lifted and then raise the formwork to the next vertical position on the tower, making the system completely independent of the crane. Wide walkway work platforms are integrated into each climbing frame unit around the entire circumference of the tower. It’s designed to safely cast an entire section of the tower ring in one day.
More than 80 containers of equipment was shipped from the Austrian Doka headquarters in Amstetten to Port Newark / Elizabeth Terminal in N.J., then by truck to the project site in Massachusetts. Approximately 26,000 square feet of formwork was supplied to the project, 13,000 square feet per tower and 228 SK175 climbing frame units. In total, the amount of formwork material supplied was equivalent to two football fields.
Workers needed to be on the working deck up to 10 hours a day so Doka designed platforms that included winter heating, portable bathrooms and clean areas for tool boxes. The construction involves two shifts and 450 people working at the site Monday through Saturday. When complete, four 4,900 pumps will drive 360,000 gallons of water per minute into each of the towers. The towers should be operational by May 2012.