2024 Award Winners and Nominees
Project Name
Nitro WW I Memorial Bridge (Call 001 Nitro to St. Albans Bridge)
Description
“The Road to Prosperity program is the centerpiece of my vision for West Virginia's economic recovery”. Jim Justice, the governor of West Virginia, put in to place a series of funding measures that are expected to generate approximately $2.8 billion for highway and bridge construction and maintenance all across West Virginia. In 2019, it was announced that the second largest project under this initiative would be built to correct a major bottleneck in the area at the Donald M. Legg Bridge. This bridge carried traffic 1400 feet across the Kanawha River along Interstate 64 for almost 60 years. Connecting Nitro, WV to St. Albans, WV this 3-span bridge handled 69,500 vehicles per day according to 2013 WVDOH studies. The bridge was to be replaced and renamed the Nitro WWI Memorial Bridge. Also, part of this project were nine new overpasses and 3.9 miles of widening between Nitro, WV and the U.S. 35 Interchange.
The bridge itself was requested by the governor to be designed to last 100 years and the requirements for the ready-mix concrete involved extensive testing. Heidelberg Materials, worked in conjunction with Brayman/Trumbull JV to establish custom versions of the standard WVDOH concrete catalog for the project. Concrete mixes for the project included mass concrete, Class H bridge deck, and a custom version of Class B a staple mix for the WVDOH. When developing these mixes, CTL group from Chicago, IL was brought on board for the extensive testing required. Above the standard concrete testing, spacing factors, hardened air, freeze-thaw resistance, NT Build 492 Chloride Penetration Testing, Acid Soluble Chloride testing and a more stringent plastic air content range were required by specification. Outside of that, standard WVDOH mixes were utilized for the rest of the project.
The mix designs for the project were all developed using ternary cementitious blends of Class F Fly-Ash from the local John Amos Power Plant and Ground Granulated Blast Furnace Slag from Heidelberg Materials. Heidelberg Materials sourced the cement from Nazareth, PA for the project, and the aggregates were provided by Hilltop Companies via barge to the ready-mix plant. The concrete plant was located .5 miles from the bridge which made large placements easier to supply throughout the length of the project. To date the project has received roughly 25,000 yd3 of concrete with 11,500 yd3 of that requiring the service life mix designs.
Evidence
An interesting feature of the concrete bridge deck was the way the rebar was prepared. Most of the rebar for the deck spans on the project were tied together using the TYBOT technology. TYBOT technology is a robot that self-ties horizontal bulk rebar sections at 1200+ ties per hour. There were 181,922 ties done by a robot across 86,835 square feet.
One benefit that was originally unforeseen on this project, is the amount of carbon that was reduced when building the service life portion of the project. Because of the ternary nature of the mix designs and proximity to supply chain the service life mix designs all carried a lower GWP than their respective standard mixes. For example, a standard WV Class H bridge deck mix design would carry a GWP of 226.01 out of the plant where it was produced. The GWP of the service life bridge deck for this project is 177.72. This represents a 21% reduction in GWP for the bridge deck portion of the project. The mass concrete used in the piers and foundations of the bridge would normally be Class B concrete for WV. Although the reduction in carbon for this concrete is only about 5% of a standard class B, the mass concrete mix used for this project carried a GWP of 209.03.
The benchmark in the 2021 Industry Average EPD from the NRMCA is 261.83 kg/CO2e for 4000 psi mixes and the service life mix used on the bridge deck (Class H) provided a reduction to that average by 32%. Using the same study for 3000 psi the benchmark would be 222.44 kg/CO2e and the mass concrete mix used for the project would provide a reduction of 6% to the output on the project. The amount of CO2 reduction be the equivalent of removing 123 gas powered vehicles from the road for a year or 1.44 Million miles driven by an average gasoline-powered vehicle.
In summary this project utilized mix designs that are outside of the standard scope for bridge construction in the state of West Virginia. The ternary blends that were developed provided sustainability benefits to the project’s construction and innovative technology in rebar tying resulted less labor being used for deck placement preparation. This project is going to help alleviate major congestion and provide a safe way for the area to continue to flourish. The project is truly a road to prosperity for the state of W.V. and local economy, and because of this Heidelberg Materials would like to nominate the Call 001 Nitro/St. Albans Bridge project for the NRMCA Concrete Innovations award.
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