To the Editor:
I recently read with great interest your articles about New Yorks Metropolitan Transportation Authoritys (MTAs) decision to allow a Chinese fabricated steel orthotropic deck system for the Verrazano-Narrows Bridge.
The Bridge Grid Flooring Manufacturers Association (BGFMA) agrees with the statements made by the American Iron and Steel Institutes Thomas Gibson, as well as various lawmakers (amm.com, June 26). Although we understand the benefits of steel orthotropic deck systems, we also realize that these deck systems are very expensive to manufacture here in the United States, which leads to overseas fabrication.
Especially frustrating to us is the fact that the existing deck on the Verrazano-Narrows Bridge is a steel grid reinforced concrete deck that is nearly 50 years old and still in service.
New, modern steel grid deck systems can be designed even lighter and more durable than ones of the past. With this said, we believe that a new American designed and manufactured steel grid reinforced concrete deck was a viable alternative to the more expensive and foreign manufactured steel orthotropic deck currently specified. Unfortunately, this option wasnt selected in the preliminary stages of design.
Steel grid reinforced concrete decks have been an economical choice for long span bridges, where weight reduction has been a concern for many years. Just a few years ago on the Walt Whitman Bridge in Philadelphia, Aecom Technology Corp. designed a new steel grid deck filled with lightweight concrete to be a "floating deck" system that eliminated more than two dozen expansion joints. This redecking project is in the final stage of construction and will be completed within the next few months.
It is frustrating to the BGFMA, and more importantly our fabricating members, that steel grid decks are sometimes overlooked in favor of foreign supplied steel orthotropic decks. Unfortunately, history is likely to be repeated since the MTA is now in the early stages of design for an orthotropic deck system for the Throgs Neck Bridge in New York City.
Bridge Grid Flooring Manufacturers Association