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GRIDLINE, Issue #14, March 2016
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New Year, New Funding
Although the release of this newsletter does not align perfectly with the start of the New Year, we still wanted to take a moment to wish everyone a happy and successful 2016. For those who have made New Year's resolutions we know it's not always easy, so hopefully you're still sticking to them!
 We have a lot to look forward to this year including more transportation funding visibility than we've had in over 10 years. In fact, while putting Gridline #13 together last September there was a woeful lack of confidence that a new long-term bill would be passed by year-end. But much to the surprise of many who have followed the long and consistent train of short-term extensions (36 total), a 5-year $300+ billion "FAST Act" was passed by Congress and signed into place by the President in early December. This new transportation funding bill is great news for our industry, as infrastructure owners now have more financial security to plan and fund the large multi-year engineering and construction projects. Although we have a long road ahead of us to bring the condition of our infrastructure to an acceptable level on a nationwide scale, the FAST Act is a sign of support by Congress and a huge step in the right direction!
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BGFMA Design Program - Updated Version (V2.2) Available
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Cover sheet from updated BGFMA design program V2.2
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The original BGFMA Design Program was released in mid-2013 and has been available to users upon request ever since. Because many of you have this original version, we felt it important to announce that updates were made to the program in October 2015 (Version 2.1) and again early this year to fix typos, formatting errors, and minor bugs originally written into the code. This updated program, version 2.2 (V2.2), is now available upon request. Although most of the changes were to VBA settings or cosmetics, there were a few minor updates to note below:
- Changed cross bar spacing for fully filled grids utilizing a WT3x4.5 main bar (V2.1)
- Added non-composite effects to LRFD summary in accordance with AASHTO Appendix 6.2 (V2.1)
- Updated / changed standard grid configuration / selections for various deck types (V2.1 & V2.2)
- Slightly modified section and punch dimensions / locations for several grid main bar types (V2.2)
Again, none of the updates were major, so any designs that were completed previously on the original version or V2.1 should still be acceptable; however, designs completed in older versions should always be verified in the most current program. If you have questions, or would like to receive the most up-to-date program please email us at bgfma@bgfma.org.
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BGFMA Brochure: Grid Reinforced Concrete & Exodermic® Bridge Decks - Table Correction
Corresponding to bullet 2 in the BGFMA Design Program update above, a typo was recently discovered in the "Properties and Span Capacities" table for full depth grid decks utilizing 3" (WT 3 x 4.5) main bars. The cross bar spacing for this system is 6 inches based on design and fabrication standards, not 5 inches as shown in the design table. Similar to many of the program updates pointed out in the above section, this cross bar spacing correction does not significantly impact the deck properties or span capacities. Furthermore, at this time we do not plan to update the brochure, but thought it important to point out the correction in the event someone noticed a conflict between our tables and shop drawings. |
| | Typo in full depth grid table |
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Precast Exodermic® Deck Panels Used to Rehabilitate 65-Year Old Mathis Bridge
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| | Typical deck spall on existing Mathis Bridge deck |
Built in 1950, the 3-lane Mathis Bridge currently carries Route 37 eastbound over the Barnegat Bay and is a vital route for commuters traveling between Island Heights and Seaside Heights in Ocean County, New Jersey. Route 37 travelers heading west utilize the newer and larger raised Tunney Bridge, which was built in 1972 and also carries three lanes of traffic. The Mathis Bridge is comprised of over 60 flanking and approach fixed spans, and a double-leaf bascule span, and is only a football field short of 1-mile long. Due to normal deterioration triggered by the structure's age and damage caused by an encounter with Hurricane Sandy in 2012, many components in the spans are in poor condition and ready for replacement. The declining condition of the structure spurred the NJDOT to let a 3-year $79 million rehabilitation project in late 2014, with work officially starting in late 2015. Rehabilitation plans and specifications were prepared for NJDOT by Parsons Brinckerhoff (Lawrenceville, NJ) with a scope that includes replacement of bridge deck and bearing assemblies, substructure and structural steel repairs, painting, safety improvements, upgrades to the electrical and mechanical components for the machinery in the movable span, and more.
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| | New precast Exodermic® panels being placed on each approach spans |
The eastbound Mathis and parallel westbound Tunney Bridges are not just an important means for daily commuters, but also a critical evacuation route from the barrier island. Considering the possible importance of needing both structures during the summer hurricane months, the contractor will only be permitted seasonal closures to the Mathis Bridge between November and May. During construction eastbound traffic will be diverted to the Tunney Bridge, which is equipped with a movable barrier and will maintain one eastbound and two westbound lanes. In the unlikely event there is a need to evacuate the island while the Mathis Bridge is closed for construction, all three lanes of the Tunney Bridge would carry eastbound traffic off the island.
Deck replacement in the short 6-month construction sequences is possible using precast Exodermic® panels that accelerate installation. The deck panels and components, such as scuppers, railings, lighting boxes and safety walks are all being prefabricated off-site. Over 175,000 square feet of Exodermic® deck panels are being fabricated by BGFMA member company L.B. Foster and will be replaced in the three construction seasons with the first panels to be set in early 2016. The galvanized grid panels are being precast close to the project site, and will utilize galvanized rebar and high-performance concrete (HPC). The deck closure pours will be completed using high early strength grout, and the deck will be finished with a ¾" polyester polymer concrete (PPC) overlay after all the panels are in place. With this project currently in the early stages, we will plan to provide an update in the next Gridline newsletter summarizing the first phase of seasonal construction. Also, for those going to National Harbor, MD in early June for the International Bridge Conference (IBC), representatives from the consulting firm Parsons Brinckerhoff will be presenting an update on the Mathis Bridge project so make sure to check it out.
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