Steel reinforced concrete is known to be the most tried and true method of construction. We have tried it for over 100 years and found that one thing remains true: embedded steel will corrode, causing early failure of the concrete around it.
Contrary to what you see in the media, the US isn’t very progressive. Well, at least when it comes to the trial and acceptance of new and innovative building materials (is this where I scream discrimination?)!
Alas! For the first time in the United States, a 100% STEEL FREE bridge is being designed and constructed. The bridge will replace the current Hall’s River Bridge spanning Hall’s River in Citrus County, Florida. In lieu of steel, a combination of three types of corrosion resistant materials will be used: Glass FRP rebar, carbon FRP strands, and hybrid composite beams (HCB). This is an experimental project that will be monitored long term and will be overseen by the FDOT Central Office and FHWA (Federal Highway Administration).
The presentation of the plan highlighted the problems related to the corrosion of steel reinforcement. Accelerated deterioration of the surrounding concrete, decreased service life, and high service and repair costs were all areas that FDOT intended to improve upon. It’s no secret that steel reinforced structures take a beating in coastal marine environments. While prevention methods and repairs are a Band-Aid, they can be expensive and, of course, are only temporary fixes to the cancer that is corrosion. Instead of treating the symptom, FDOT has eliminated the issue completely, by developing a 100% FRP bridge design that will lower maintenance expenditures over its lifespan while increasing its service life.
Matt Kero, our VP of Engineering, was able to attend a meeting in May where the bidding for this project began. The long term testing on our FRP rebar is not yet complete, so it is unlikely that GatorBar™ will be put into any phase of this project. The bridge construction is set to begin summer of 2016.
However, any news that’s good for the FRP world is good for us! The faster we can get FRP products embedded in concrete, the faster we can get test results. In a world where data is boss, we’ll need a lot of it to prove our case: FRP materials are a sustainable reinforcement product, and using them will extend the life of concrete infrastructure.
We already have 100 years’ worth of data in the books proving that steel embedded in concrete will rust. Place your bets, folks, I’m going with the latter.