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Repurposing bridge beams
Oklahoma City recycling program saves county bridges.

Recycled steel beams are stored at 20 county-government-sponsored staging areas across Oklahoma while they await incorporation into as many as 350 bridges.

At the intersection of three major interstates in Oklahoma City lies a four-mile stretch of highway known as the Crosstown. The Crosstown was built in 1966 and is the convergence point for I-35, I-44, and I-40. It was designed to carry as many as 76,000 vehicles daily in three lanes each direction, partially supported on an 8,800-foot-long bridge. By 2005, the highway was carrying 125,000 vehicles daily. The added stress on the bridge was costing $1 million in emergency repairs each year.

The problems began in 1989 when a crack was discovered in one of the pier beams. The deteriorating Crosstown was immediately closed for emergency repairs, which created significant transportation problems on one of the few interstates that stretch from coast to coast. Not only is I-40 a major thoroughfare for residents of Oklahoma City, but for all of America. This event attracted national attention and set in motion an effort to replace the facility that would span more than 20 years.

The Oklahoma Department of Transportation (ODOT) embarked on one of the largest projects since the interstate system was completed in the 1970s – taking down the Crosstown and rebuilding it one mile south. The new $670 million I-40 Crosstown would be designed to carry 173,000 vehicles daily on five lanes in each direction. As the deconstruction of the bridge was planned, ODOT realized that about 1,800 of the steel longitudinal beams were not deficient and had 50 to 70 years of good use left. Armed with this knowledge, the officials began to work with Oklahoma Governor Mary Fallin and the state legislature to develop and fund an effort to recycle the beams for use in county bridges.

Oklahoma ranks second in the nation for structurally deficient bridges. Much like the state highway system, most of Oklahoma's county road system was built in the early 20th century as a farm-to-market and general transportation network. Today, the roads are not capable of handling heavier trucks at increased operating speeds. With its 84,767 miles and 14,301 bridges, the proper care and maintenance of this massive system is often beyond the fiscal reach of most county governments. By today's standards, more than 4,000 of Oklahoma's county bridges rate as structurally deficient.

Steel beams are removed from the old interstate bridge for reuse in county bridges throughout Oklahoma.

After careful research, ODOT, Governor Fallin, and the legislature crafted and presented a plan in October 2011 that called for recycling the beams to fix the county bridges. ODOT and county officials completed a logistics plan to move and store the beams. This plan started with mandating the careful removal of the bridge deck from the beams during the deconstruction project. The beams would then be readied for removal and lowered from the piers where they are initially inspected, serialized, and prepared for shipping. The beams would then immediately be loaded onto trucks and shipped to one of 20 county government-sponsored beam staging areas across the state. Upon arrival, the beams would be unloaded by county forces and stored while they await incorporation into a subsequent bridge replacement project. The initial assessment indicated that the beams could be re-tasked in as many as 350 bridges.

This forward-thinking initiative was not without its challenges. The logistics of removing, transporting, and storing 1,800 beams was daunting. The I-40 bridge is in a busy section of downtown Oklahoma City. Just securing the beams would take a major mobilization effort. But the major issue was how to fund this initiative.

With the collective support of the governor and the legislative leadership, it was determined that additional long-term funding for county road improvements could be facilitated by enhancing the existing County Improvements for Roads and Bridges (CIRB) fund. The funding necessary to construct the recycled beam bridges would be generated by increasing the CIRB fund from the current 15 percent share of the Motor Vehicle Excise Taxes, Licenses, and Fees to 20 percent.

The additional 5-percent commitment to the CIRB fund will be phased in over a three-year period, and the initial proceeds are reserved to assist in implementation of the direct beam recycling plan. The direct beam recycling effort is anticipated to be fully funded by year four of the program. For the long term, the additional funding will enhance the CIRB Five Year Construction Work Plan and be invested in critically needed county projects selected, developed, and implemented by the counties under the direct oversight and supervision of the department.

The deconstruction project is progressing rapidly and is ahead of schedule, with more than 1,100 beams successfully removed, inspected, serialized, and readied for shipping. More than 700 of those beams have been shipped to the county staging areas. The delivery of the beams is expected to be completed before the end of 2012. The additional deposits to the CIRB fund begin in January 2013 and will fully mature in 2015. These deposits will generate an estimated $45 million for recycled beam bridge construction during that time period. It is anticipated that all of the targeted beam direct recycling projects will be competitively bid and awarded to contract by the end of State Fiscal Year 2015.

The initiative is a shining example of state and local elected officials and governmental entities working together with innovation and creativity to reduce the cost and increase the efficiency of transportation infrastructure investments. This initiative represents the single-largest non-highway bridge infrastructure investment in Oklahoma's transportation history, and is quite possibly the only direct recycling effort of its kind in the nation.

Crews carefully remove deck from the 8,800-foot-long Crosstown interstate bridge during deconstruction to recycle about 1,800 steel beams.
Photo: Greater Oklahoma City Chamber/Oklahoma
Department of Transportation

This article was provided by the Greater Oklahoma City Chamber (www.okcchamber.com) with contributions from the Oklahoma Department of Transportation (www.okladot.state.ok.us).

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