AZZ's GalvaBar™ Helps Expedite Completion of Bridge Replacement Project
Nestled in Northeast Iowa and on the banks of the Wapsipinicon River, the town of Independence was home to some of the earliest settlers west of the Mississippi. A progressive city with a small-town feel, Independence preserves a fascinating history while focusing on the modernization of its amenities and transportation infrastructure.
Just east of town, a timeworn two lane bridge spanning Buffalo Creek carried traffic along 220th Street since its construction in 1928. In a declining state of repair and subject to frequent flooding, replacement of the bridge became a priority for Buchanan County Engineer Brian Keierlebler.
As one of the area’s major traffic thoroughfares, pressure was high to expedite completion of the replacement structure without compromising safety or projected service life. With many options to choose from, Keierleber chose ASTM A1094 compliant galvanized reinforcement for its long-term corrosion resistance, durability and—thanks to a game-changing corrosion resistant rebar product—ability to significantly reduce project lead times.
Introduced by AZZ Metal Coatings in 2016, “GalvaBar” is a Continuously Galvanized Rebar (CGR) process where properly cleaned rebar is in the molten zinc for only a few seconds and the coating is pure zinc except for a very thin alloy layer at the interface between the zinc and the steel. The coating not only is very adherent and impact resistant, but unlike traditional batch galvanized rebar, is also is very formable and withstands all post coating forming operations without cracking or peeling. While the Continuous Hot Dip Galvanizing steel sheet process has been used for over 8 decades to produce galvanized steel sheet and wire products, it is a recent and game-changing development for rebar.
“If we used standard construction methods, we wouldn’t have completed the project this year,” Keierleber stated. “The galvanized and coated H-piling eliminated the need to construct coffer dams. With all the flooding Taylor Construction could not have gotten the coffer dams constructed this year. The Bridge would be closed until the spring of 2019.”
The reasons for streamlined construction schedules for projects utilizing GalvaBar are numerous, but at the forefront is, unlike traditional batch galvanized rebar, GalvaBar is formable after processing—without flaking, peeling or cracking. This formability allows for shipment direct from the fabricator to the jobsite; traditional galvanized rebar must be formed by the fabricator, shipped to a galvanizing facility for processing (which often adds days to the process) and finally transported to the jobsite.
“We’re essentially removing a step from the supply chain,” AZZ’s Mike Stroia explains. “This saves a significant amount of time and fabricators appreciate controlling corrosion resistant rebar in inventory without logistics of additional shipping, tagging or bundling. Additionally, because you can fabricate GalvaBar with any rebar equipment, a consistent flow of product is ensured and the need for on-site field changes can quickly and easily be addressed.”
Despite record rains and lost time due to severe flooding, the Buffalo Creek bridge replacement project in 2018. It was a very nice Christmas present to the local residents.
Keierleber, pleased with the results, plans to utilize GalvaBar on future projects, “Insanity is doing the same thing over and over again and expecting different results,” he laughs, “I’m glad we finally made a change.”
The American Galvanizing Association (AGA) worked with Keierleber to install a video camera with live feed on the grounds of the Buffalo Creek Bridge project. Check out the time-lapse footage below: