Spanning the News: Concrete Evidence

May 2, 2007

Chunks of concrete can come from bridges or from anyone crossing the street.

The Michigan Department of Transportation (MDOT) was trying to sort out legitimate claims from the false ones during the first month of spring. At press time, six incidents of falling concrete in the metro Detroit area had been investigated, and despite some conflicting evidence MDOT launched an aggressive inspection program of all suspected bridges.

Chunks of concrete can come from bridges or from anyone crossing the street.

The Michigan Department of Transportation (MDOT) was trying to sort out legitimate claims from the false ones during the first month of spring. At press time, six incidents of falling concrete in the metro Detroit area had been investigated, and despite some conflicting evidence MDOT launched an aggressive inspection program of all suspected bridges.

“We are getting some reports where somebody said concrete hit their car and then we went out and looked at it and nowhere on the bridge can you see evidence of falling concrete,” MDOT spokesman Bill Shreck told Roads & Bridges. “The concrete also doesn’t match what would be in the bridge. Now if we have a report of a bridge hit we contact the police and have them go out and look at it to make sure it all matches up.”

Shreck, however, admitted there were aging bridges—360 to be exact—in Wayne, Oakland and Macomb counties that deserved some extra attention from bridge maintenance crews. Those spans were constructed in the 1960s and ’70s using a lightweight slag aggregate in the concrete. Premature failure forced MDOT to stop using the aggregate altogether over 30 years ago. Since then, 240 bridges have been reconstructed, leaving 462 in the metro area with roots to the ’60s and ’70s, when funding was tight at MDOT. Of the 462 still standing, up to 30% may have been built using the slag aggregate.

“Because there was so much of that slag in the area we used it back then because it was inexpensive,” said Shreck. “It also was an industrial material that [MDOT] thought would be beneficial to use if it did indeed work.”

Despite the reports, MDOT is not ready to blame the aggregate as the sole reason behind the falling concrete. Shreck said freeze-thaw cycles, vehicle loads and salt usage could be other factors.

“We have a construction technology area that can study those things, and they are currently looking [for a cause],” he said. “Our main focus is to look at the bridges and make them as safe as possible.”

Workers were out checking the 360 bridges marked as possible trouble spots by MDOT. Inspection crews were using the sounding and scaling technique, where a hammer hits spots on the bridge in an attempt to find hollow areas where loose concrete may be sitting. At press time, Shreck said one-third of the inspections were complete. The cost to do each span is approximately $5,000-6,000, which will be taken out of maintenance funds.

MDOT usually inspects bridges once every two years unless the agency feels a particular one may become a problem. The agency has executed an aggressive campaign to improve the elevated structures over the last 10 years. In 1996, 67% of bridges statewide were listed in good condition, while 62% in the metro area received that mark. Currently, the good condition list has grown to 83% statewide and 80% in the Detroit area.

“One-hundred percent might be possible, but at some point something is going to fall into poor condition, especially at current funding levels. We are using the funds that we have to make the bridges as safe as possible,” said Shreck.

Mississippi bridge still being discussed

Officials from Missouri and Illinois met in mid-April to discuss options for a bridge crossing the Mississippi River between St. Louis and East St. Louis, according to the St. Louis Post Dispatch. Both sides agree that a span is needed, but there are differences as to how big the structure should be and how funding should be generated.

Missouri has been in favor of an eight-lane span, while Illinois has been suggesting a four-lane companion bridge to the Martin Luther King Bridge. Missouri was going to use tolls to cover some of the cost of their $1 billion design, which did not sit well with Illinois officials.

The April meeting did result in the decision to go with the $1 billion bridge, with Missouri looking beyond tolls as a way of funding the project. Congress has approved $239 million in federal money for the new span.

FHWA: go ahead with I-73 design

The Federal Highway Administration (FHWA) has given the OK to design work on I-73, a $4 billion, 70-mile interstate between Roanoke and the North Carolina line in Virginia. The record of decision is the final step in the National Environmental Policy Act process, which includes public involvement and considers the possible environmental impacts of transportation projects.

“We have cleared a major milestone in the development of I-73,” said the Virginia DOT’s Salem District Administrator Richard Caywood, P.E. “This will be a very involved, very expensive project.”

Estimates indicate designing the new roadway could cost about $330 million, and construction costs could top $4 billion. Currently, about $13.3 million, including about $8.8 million in federal earmarks, has been allocated in VDOT’s Six-Year Improvement Program for design and construction of I-73.

In the coming months, VDOT will work with local, state and national elected officials to identify segments for initial designs. I-73 in Virginia will reflect a context-sensitive solution wherever possible. As defined by the FHWA, context-sensitive solutions involve affected citizens, officials, business and property owners and others in developing a “transportation facility that fits its physical setting and preserves scenic, aesthetic, historic and environmental resources while maintaining safety and mobility.”

Two left to fix MoDOT’s bridges

The Missouri DOT (MoDOT) has lost one of the competitors in its search for someone to carry out its Safe & Sound Bridge Improvement Program. Partnership Missouri, a consortium of engineering, construction and financial service companies led by Transfield Services and Macquarie Securities (USA), has withdrawn from consideration for the design-build-finance-maintain contract to improve more than 800 of Missouri’s worst bridges.

“After working with us for several months, Partnership Missouri withdrew because they felt they would be unable to submit a proposal that would be responsive to the requirements of our [request for proposal],” Project Director Ken Warbritton told Roads & Bridges.

Partnership Missouri’s withdrawal leaves two teams—Missouri Bridge Partners and Team United—to contend for the contract.

The state expects to award the contract, with an estimated capital cost of $400-600 million, this summer. Initial technical proposals from the teams were due on April 6. Final proposals are due in June.

La. looks for new road revenue

Louisiana is another state struggling with too little funding for highway construction, The Times of Shreveport reported. State legislators are scrounging for money to fill a $14 billion backlog of construction projects that are necessary, according to the Louisiana Department of Transportation and Development (LaDOTD).

The latest effort to snag more funding involves shifting money from the state’s general fund to the Transportation Trust Fund (TTF). The chairmen of legislative committees that handle highway matters support legislation that would take $256 million from vehicle and parts sales tax revenue, $200 million in excess mineral revenue and $40 million in truck registration fees and put it into the transportation fund.

The chairman of the state Senate Transportation, Highways and Public Works Committee, Noble Ellington (D-Winnsboro), reportedly said the plan would “put dependable, adequate funding into our transportation fund without raising taxes.”

The plan also would start paying for the retirement benefits of LaDOTD employees and for state police to conduct traffic control from the general fund instead of the transportation fund. Retirement benefits and traffic control currently cost the TTF $85 million and $40 million, respectively.

If the state does not transfer money from the general fund into transportation, it may have to consider the much less appetizing option of increasing taxes, Jennifer Marusak, spokeswoman for the Good Roads Association, told The Times. She was referring to actions such as indexing the gasoline tax to keep pace with inflation, increasing the maritime diesel sales tax or hiking motor vehicle registration fees.

The plan’s backers were uncertain of how the proposal would fare in the Louisiana Legislature.

Pa. commissioner leads effort to form I-81 coalition

Interstates, by their name, extend into multiple states with separate planning processes and separate programs to solve the common problems that crop up along an interstate. Concerned citizens in the six states passed through by I-81 are trying to form a coalition that would work toward the best common solutions to problems along I-81.

“At this time, the only real planning mechanisms we have are local,” Cumberland County, Pa., Commissioner Rick Rovegno told The Sentinel, Carlisle, Pa. “We need to have a planning body that has a more regional scope.”

Rovegno and several colleagues have tentatively scheduled a planning meeting for the I-81 Corridor Coalition during the week of Sept. 10-14.

“The primary objective of this planning group would be to facilitate, coordinate and synergize all planning efforts and transportation investment in the corridor,” Rovegno explained to The Sentinel.

George Schoener, executive director of the I-95 Corridor Coalition, said he planned to attend the I-81 meeting. He said starting such a coalition was difficult and often unsuccessful. He said the I-95 group started small and grew, gaining federal funding along the way. The I-95 Corridor Coalition has engaged in regional efforts such as developing a transponder that can be used for electronic toll collection from Virginia to Maine, identifying transportation bottlenecks and creating standards for quick clearance of traffic incidents.

Mitchell named ACPA director of airports

The American Concrete Pavement Association (ACPA) has named Gary L. Mitchell, P.E., director of airports. Mitchell previously served as regional director of airports for the Southeast Chapter of ACPA. He succeeds James Lafrenz, P.E., as national director. Lafrenz retired.

Mitchell also is the research and development liaison to the Washington, D.C.-based Innovative Pavement Research Foundation and is the industry’s primary airfield pavement research liaison to the National Concrete Pavement Center, or CP Tech Center, at Iowa State University in Ames.

Also, ACPA has published a guide to pervious concrete pavements titled, Stormwater Management with Pervious Concrete Pavement. The six-page technical publication contains practical knowledge about pervious concrete pavement design, construction and maintenance.

Useful tube

YouTube.com is known for its unusual, amateur video clips. Whether it is Keepon, a robot that looks like a pair of tennis balls with eyes, dancing to rock music or one woman’s tribute to Kurt Vonnegut and his rants on how humans are trashing Earth, anyone can post any amateur video they choose. It is the Wild West of the new web media, and the motto is, Expect the unexpected.

So why would a respectable government agency employ YouTube to publicize a video of a simulated bridge collapse?

“We’re trying to meet people where they are, such as the Internet,” Lloyd Brown, communications director for the Washington State Department of Transportation (WSDOT), told the Seattle Post-Intelligencer, “rather than assuming they’ll come to us for meetings, etc.”

The videos are simulations showing how the S.R. 520 Evergreen Point pontoon bridge could fail during a catastrophic windstorm or earthquake.

In the earthquake video, for example, the pillars of the bridge’s east high-rise section shake, crack and break, and the bridge plunges into Lake Washington.

“We have a critical infrastructure in danger of catastrophic failure,” John Milton, a WSDOT engineer and project manager for the bridge, told the Seattle Post-Intelligencer. “There are 30,000 linear feet of cracking on the 520 bridge right now. . . . We want people to understand that this bridge, as well as the Alaskan Way Viaduct, is very vulnerable.”

WSDOT has plans to replace the S.R. 520 corridor with a new six-lane facility that will be seismically sound and safe. The planned road includes a new Portage Bay Bridge and Evergreen Point Floating Bridge with full shoulders and a bike and pedestrian path through the entire project corridor. The floating bridge pontoons will be large enough to support future high-capacity transit.

The simulations can be viewed on www.youtube.com by searching for “WSDOT 520 Bridge” or on the S.R. 520 project site (www.wsdot .wa.gov/projects/SR520Bridge.com).

Traffic detected

A traffic-incident-detection system has been installed on the Throgs Neck Bridge in New York City. The system uses cameras to capture pictures of vehicle movement on the bridge, then analyzes the movement and automatically alerts traffic management center staff of any vehicle stopped on the nearly 3-mile bridge, which carries I-295 over the East River.

Circle widens

Parsons Brinckerhoff will be the owner’s representative of BluePrint 2000, an intergovernmental agency of the city of Tallahassee and Leon County, Fla., on a $17 million design-build road improvement project in southeastern Tallahassee. The project involves widening from two to six lanes a 2.3-mile section of Capital Circle Southeast. Elements include a new storm-water system; work on the potable water, sanitary sewer and reclaimed water systems; extensive landscaping; and electrical and signal installation.

Kentucky moves

Bizzack Construction LLC has won a $4.8 million contract to replace an old, winding, narrow highway in Kentucky, WKYT-TV Channel 57, Frankfurt, reported. The project involves relocating 2.57 miles of KY 7 beginning at the intersection of KY 7 and KY 15 at Jeff and extending south to Viper. The new location will make the road much safer than its previous path squeezed between a mountainside and the North Fork of the Kentucky River. The road carries about 5,800 vehicles per day with a large percentage of trucks.

Sponsored Recommendations

The Science Behind Sustainable Concrete Sealing Solutions

Extend the lifespan and durability of any concrete. PoreShield is a USDA BioPreferred product and is approved for residential, commercial, and industrial use. It works great above...

Powerful Concrete Protection For ANY Application

PoreShield protects concrete surfaces from water, deicing salts, oil and grease stains, and weather extremes. It's just as effective on major interstates as it is on backyard ...

Concrete Protection That’s Easy on the Environment and Tough to Beat

PoreShield's concrete penetration capabilities go just as deep as our American roots. PoreShield is a plant-based, eco-friendly alternative to solvent-based concrete sealers.

Proven Concrete Protection That’s Safe & Sustainable

Real-life DOT field tests and university researchers have found that PoreShieldTM lasts for 10+ years and extends the life of concrete.