Working through the floods and flows of the Mississippi River always poses challenges – but when new construction rises from the river bottom just 19 feet from the bridge it replaces, complexities multiply.
With a design-build contract intended to speed construction of the Champ Clark Bridge (part of the U.S. Route 54 corridor connecting Louisiana, Missouri, with Illinois), Prime Contractor Massman Construction Co. and their design partner HNTB, both from Kansas City, Missouri, developed plans and contingencies to work around the inevitable high waters.
Originally built in 1928 to accommodate Model A Fords – not the 4,000 cars and 18-wheelers that now cross the bridge every day – the existing bridge became functionally obsolete, so the Missouri Department of Transportation (MoDOT) and Illinois Department of Transportation (IDOT) partnered to fund a safer, low-maintenance bridge.
“In our Request for Proposals, we told teams we weren’t looking for anything fancy,” said Keith Killen, MoDOT’s Project Director. “We wanted a 100-year bridge to meet the needs of everyday commuters and freight that travel this route.”
The new design includes a durable overlay to extend the deck life, wider navigational spans, and two 12-foot lanes with 10-foot shoulders to replace the 10-foot lanes – with no shoulders – on the existing bridge. To keep the preferred alignment, the team placed the new bridge just 19 feet downstream from the existing structure.
When the new bridge opens in fall 2019, motorists will experience a reliable, safer Mississippi River crossing, Killen said. An elevated Illinois approach will also help eliminate future flood closures.
Thanks in part to a $10 million TIGER grant awarded by the U.S. Department of Transportation in October 2015, the Champ Clark Bridge is the first design-build project in MoDOT’s Northeast District.
“We decided that delivery method would be able to get us a project that met the grant’s obligation date of September 2017,” Killen said. “In design-build, you’ve obligated the money when you release the Request for Proposals.”
With MoDOT and IDOT splitting costs that remained after the TIGER grant, they released the project’s Request for Qualifications in January 2017 and the Request for Proposals to their shortened list in March 2017. Massman/HNTB was awarded the $60 million contract in June 2017.
In addition to the scheduling benefits, design-build delivery allowed for higher DBE participation goals, Killen said. “The goals of 12 percent for construction and 16 percent for design are a little more aggressive than we normally see on smaller projects in Pike County, but with design-build, we tried to help out the DBE folks as much as possible.”
The contract also specified a minority participation goal of 3.1 percent, based on the local Pike County population, and a female participation goal of 6.9 percent, based on Missouri’s statewide goal. In the project’s first year, Massman exceeded those goals and received IDOT’s Above and Beyond Award for DBE and Workforce Diversity Performance.
Navigating High Waters
With design-build, Massman was able to start construction shortly before final design completion in fall 2017, helping to overcome the project’s biggest challenge.
“Any time you work on the Mississippi River, the potential for flooding is always around,” Killen said. By late 2018, flooding already caused three delays or schedule revisions.
However, “Massman did a great job attacking the project early to make as much progress as possible before any flooding issues,” Killen said. “They completed the underwater work last April, so when the high flows came early last summer, they were able to work on the bridge superstructure and stay on schedule.”
The flooding did force Massman to reroute some deliveries. “Most of our deliveries came in from the Illinois side, which is lower,” Killen said. “We built a haul road into the river and a load-out dock on piers, then cranes off-loaded materials onto a barge.”
Once the river flooded, Massman needed to off-load deliveries from the higher-elevation Missouri side. However, “The existing bridge has a 40-ton weight limit,” Killen noted. “For some loads we got an overweight permit, but we had to be strategic when taking oversized loads across that bridge. All of our structural steel came in from the Illinois side, but we did have some reinforced concrete beams come across the bridge, and all our deck panels came in on the Missouri side.”
Precast Panels and Low-Maintenance Overlays
The bridge includes a traditional cast-in-place deck on the precast concrete beams, but on the structural steel girders that cross the river from the Missouri abutment to the Illinois bank, the design specified 181 precast panels.
“Each of those panels is 9 inches deep, 46 feet wide, 9 feet long, and weighs 48,000 pounds,” Killen explained. “After they place the panels on top of the girders, they do concrete closure pours in the one-foot joints between panels.”
The precast panels accommodated the construction schedule. “Massman knew deck pours would be needed during winter months,” Killen said. “The precast panels were cast off-site during the summer and fall in a more-controlled environment. Instead of trying to do major deck pours in the winter, they’re doing the smaller joint pours whenever they get good weather. That gave them more flexibility and speed of construction.”
The new bridge also includes a polyester polymer overlay on the cast-in-place and precast deck panels. “It’s a three-quarter-inch overlay that seals the entire deck and provides a durable wearing surface to reduce maintenance and prevent salt or chloride from eating at the concrete,” Killen said.
Cranes, Netting, and Increased Safety
Building next to the existing bridge required Massman to bring a large crane fleet consisting of a Manitowoc 999, 2250, 4000, 4100, and 7000. On the 7000 crane, one of only six in the world, they started with 200 feet of boom and added an additional 100 feet as needed.
The project’s proximity to the still-operational, 90-year-old bridge created a unique safety hazard. “Because the existing bridge is only 20 feet wide, trucks often clip their mirrors on the truss as they drive across,” Killen said. “To prevent those from falling and landing near workers below, we put netting on the existing bridge to catch any debris.”
Early in the project, Massman fixed another safety issue. “A lot of large trucks cross that bridge, then come to the intersection of U.S. 54 and Missouri Route 79 about 300 feet off the end of the old bridge,” Killen said. “That intersection wasn’t wide enough for large trucks to make their turns without getting out of their lane or waiting for other cars to clear.”
To solve the issue, Massman opened up the south leg of the intersection and moved the curbs back. They finished that work in fall 2017.
Construction of the new bridge deck began this winter and will continue through the spring, with roadway pavement put in place this summer. After the new bridge opens to traffic this fall, Massman will demolish the existing bridge by spring of 2020.
Illinois Department of Transportation; Jay Wavering, Project Engineer
Prime Contractor: Massman Construction Co., Kansas City, Missouri; T.J. Colombatto, Project Manager; Josh Hanrahan, Project Engineer
Design Services: HNTB, Kansas City, Missouri; Hans Hutton, Chief Engineer; Jeff Smith, Bridge Section Manager
“We don’t often get projects of this size in northeast Missouri,” Killen said. “We knew it was a high-profile project, so we wanted to leverage this opportunity to communicate the need for people going into engineering and the construction trades industry.”
To achieve that, MoDOT developed a STEM (science, technology, engineering, and math) outreach program. First, they worked with area high schools on a design challenge for an interpretive panel that reflects the history of the existing bridge.
“We also went into classrooms to talk about different bridge designs and bridge building,” Killen said. “We conducted a day-long STEM summer camp and had students get on a barge last fall to take a bridge tour. We tried to let students know there are a lot of opportunities to get involved in this industry.”
By the Numbers
The new Champ Clark Bridge includes:
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