From a joint project risk-management program to extremely large drilled shafts using an oscillator, the $134-million replacement of the Henry G. Gilmerton Bridge in Chesapeake, Va., features many innovations, including erecting components of a new 1,908-ft-long vertical-lift bridge beneath and above a 75-year-old twin bascule bridge.
The Gilmerton Bridge carries an average of 35,000 vehicles daily and lifts its bascule 7,500 times a year. Now in phase three, the project to replace the old bridge over the Elizabeth River began in 2009 and is scheduled for completion in 2014. The new design increases vertical clearance by 24 ft to allow ships to pass with fewer bridge openings. The new bridge's 85-ft width will carry four lanes with room for two more when needed.