Using innovative project delivery methods, the Missouri Dept. of Transportation may complete upgrades of 800 bridges in four years—a year ahead of the planned five. But as Congress dithers on enabling long-term federal transportation funding this year, MoDOT may not be able to embark upon another major program any time soon.
The so-called Safe & Sound program made Missouri the featured state at this year's International Bridge Conference, held on June 11-13 in Pittsburgh. The highlight of the program is a design-build contract to replace 554 bridges, typically 147 ft long, 24 ft wide, 60 years old and in rural areas, said Harry Koenigs, area manager for KTU, a joint venture of Kiewit Infrastructure Group, Traylor Bros. and United Contractors, including HNTB and the LPA Group as designers.
After winning the $487-million contract in 2009, the team grouped the 554 bridges into regions. "We broke the job into manageable pieces—about 120 bridges per region," he said. "We standardized plans and limited the types of structures we would use."
Standardizing allowed the team to stockpile bridge beams of certain lengths. The eight bridge types include a lightweight hybrid fiber-reinforced concrete beam patented by HB Bridge Co. The KTU team used three of the beams under a $1-million Highways for Life grant. "We have a 110-ft-long hybrid composite beam, the longest of this type in the world," said Koenigs.
MoDOT presented other examples, including the use of an "alternate technical concept" for the new cable-stayed, 1,500-ft-long Mississippi River Bridge linking Interstate 70 to Illinois. Since that state does not have design-build legislation, "we used best construction practices within design-bid-build," says Jeff Smith, HNTB bridge section manager.
The prequalified bid winner could propose major changes to a baseline design by HNTB. The team of Massman Construction, Traylor Bros. and Alberici Constructors shaved $7 million by changing drilled-shaft designs, said Smith. The 405-ft-tall towers are almost complete.