T.Y. Lin International (TYLI) is providing structural and mechanical construction engineering design, as well as detailing services related to the precast concrete operations and in-the-wet construction operations, for the Olmsted Locks and Dam project. The project is located between Illinois and Kentucky about 17 miles upstream of the confluence of the Ohio and Mississippi rivers.
TYLI’s work is under a task order type three-year contract authorized by the Water Resources Development Act of 1988 for the U.S. Army Corps of Engineers, Louisville District. The project replaces existing Ohio River Locks and Dams 52 & 53 with twin 110-foot by 1200-foot locks adjacent to the Illinois bank, and a new dam comprised of five tainter gates, 1400 feet of boat-operated wickets, and a fixed weir extending into the Kentucky bank.
This strategic reach of the Ohio River provides a connection between the Mississippi River, Tennessee River, and Cumberland River. More tonnage passes this point than any other place in America’s inland navigation system. Traffic at the Olmsted Locks and Dam location is projected to range between 113 million and 130 million tons by 2020.
- Along with overseeing structural engineering and detailing services for the precast concrete shell reinforcing placements and casting operations, TYLI is also providing structural/mechanical engineering services for the flat jack shell support systems that allow the precast segments to be positioned and aligned under several feet of fast-moving water.
- The work includes a review and checking of shop drawings and the development of a 3D model of the 116-foot by 125-foot shell segment. The model shows all rebar, embedded metals, pintles, baffle blocks, beams, tremie openings, drill collar anchorages, and air bleed holes.
- The vertical positioning system operates alongside of and integrated with the horizontal positioning system. It consists of a series of up to twenty four (24) 450-ton flat jacks, designed to allow final positioning of the shell in its proper vertical location. A complete set of redundant jacks, hydraulics and controls are included, in the event of master system failure.
- During tremie concrete operations, the ability to monitor stresses in the concrete shell, as well as uplift forces, is accomplished by using the lifting frame (provides stiffness to the system during transport) and the flat jacks as load cells. The jacks are controlled from water on the above-catamaran barge that transports the shells to their permanent location in the river.
- The lifting frame is also used to complete the tremie concrete placement through the top of the shell from above-water, once the shell is in position and the catamaran barge has moved away.
- Once the tremie concrete has been placed beneath the shells and cured, the jacking system is then transfused with epoxy, making it a permanent part of the overall monolith placement. The next segment is then moved into position.