Formwork System Helps Speed Plant Construction

Specialized concrete formwork panels were used to help keep construction on schedule during work on the Croton Filter Plant, a $1.4 billion underground water treatment plant to be located underneath the Mosholu Golf Course in Bronx, NY.

On a 12-acre site, the plant will treat 290 million gallons of water per day. The New York City Department of Environmental Protection contracted with Skanska USA Civil, headquartered in Whitestone, NY, to construct the facility, which will supply up to 10 percent of the island and areas of upstate New York with safe drinking water.

The project, which began in Fall 2006, is on a construction schedule of seven years.

As construction plans were developed, the project team identified several challenges facing timely completion of the underground facility. As a safety factor, the project team had to be cautious of the construction site located near the public, as well as key highway and mass transit facilities. The project called for extensive rock drilling, blasting and excavation, as well as the construction of two connecting water tunnels to the plant.

From a design perspective, the exterior walls are all one-faced and the interior walls are two-faced. The newer design of the facility required multi-levels stacked within a smal footprint. Additionally, mass concrete design mix and demand for faster pour rates were necessary to meet the project’s timeline and scope of work.

Skanska USA Civil relied on DOKA USA’s formwork system to resolve a number of these challenges.

“DOKA’s superior engineering allowed the contractor to move this unique project along in a secure environment,” said Cesar Hernadez, DOKA USA engineering project leader.

Working with Doka’s engineering department, Skanska used the company’s Framax Xlife framed formwork panels, ganged together, to tackle the construction of the facility’s 35-foot-high walls. The system was used for the interior and exterior walls, as well as support frames, consumable anchors and tie inner units. The full liquid head designed by DOKA engineering staff allowed the project team to achieve a rate of pour that was acceptable for the walls.

“The contractor was not only impressed by the Doka solution, but they also gained an added sense of security in knowing they would be able to keep the fast-track scheduling of placing concrete,” Hernadez said.

Doka provides wall and slab formwork systems for residential, industrial, commercial, transportation, infrastructure as well as stadium and sports arena projects. For more information about the company and it’s systems, visit www.dokausa.com.