On the floor of the jobsite, the workhorse delivery system is a telescopic belt conveyor. Putzmeister, working in tandem with Marco SAB, has provided a dozen 38-m-long, five-section model TB130 telescopic belt conveyors. The units were selected due to their size, capacity and ease of use, says Marc Aguilar, vice president of Latin American and Caribbean sales for Putzmeister America Inc., Sturtevant, Wis.

Yet the sheer size of the locks prompted the company to develop an ever larger machine, dubbed the TB200. "We took the technology from our larger units and created a new unit that is almost twice as big," says Aguilar. Already, the company has received orders for the unit at jobs in Australia and Brazil.

Placing It

Putzmeister began shipping TB200s to the site this summer. They boast a four-section boom with a reach of 60 meters. The Putzmeister unit is similar to a so-called "Creter Crane" mobile conveyer unit, which is already in use on the expansion, made by Rotec Industries of Hampshire, Ill., canal experts say.

The most hard-to-reach portions of the job require truck-mounted concrete boom pumps that include Schwing's 54-m units and Putzmeister's 58-m units—the largest in operation in Latin America. While effective, the telescopic belt conveyors and concrete pumps also create a substantial logistical headache due to the jobsite's limited space.

As a result, both lock sites have been fitted out with four large tower-crane-mounted conveyors, supplied by Rotec. The relatively compact layout of the site meant Rotec had to customize "baby" tower cranes for the project. The 54-m-tall Terex units are roughly a third of the size of those Rotec typically supplies for large projects, says Rotec CEO Robert F. Oury.

"There really weren't any surprises here," Oury notes. "It was a relatively easy adaptation of our equipment well within our experience and knowledge."

Each tower conveyor boasts an 80-m reach that can be directed around the project without resetting the tower, with a maximum placement rate of about 100 cu m per hour. Trucks deliver the concrete to the conveyers at locations on the side of the excavation away from the main work area, relieving logjams inside the congested jobsite.