Safe & Sound Bridge Improvement ProgramMissouri
Innovative approach replaces 554 bridges with speed, efficiency
• Project is nation’s first design-build system-improvement project
• Bridge closures limited to 45 days on average
• Collaboration, efficiencies add speed, reduced costs
HNTB was part of a joint venture for the Safe & Sound Bridge Improvement program, helping the Missouri Department of Transportation replace 554 bridges in the nation’s first design-build system-improvement project.
HNTB designed 12 non-standard bridges, completing four especially quickly at MoDOT’s request. Lessons from the first dozen informed standards for the remaining bridges:
• Separate teams focused on completing one of three processes repeatedly: 1) constructability and design review, 2) type size and location design, and 3) final design. That cut design time in half, ensured contractors could fabricate site-specific materials ahead of time and reduced bid prices.
• Variable tables allowed construction plans to use non-dimensional details and gave contractors information required for each site.
• All firms involved worked from a single location to increase collaboration.
Rebuilding the bridges fast limited closures to 45 days, on average, minimized traffic disruption and reduced growing maintenance costs.