Notable features of project.
Concrete filled steel grid deck.
Open grid decks can be described as small scale steel framing systems used as a bridge deck.
Original grid deck was in service for 70 years prior to replacement with an annual traffic volume of approximately.
The partially filled grid decks involve casting concrete for the lower section of the deck and including the open grid.
Concrete filled steel grid bridge decking provides a far greater life expectancy than reinforced concrete and its durability resists heavy traffic weather and deicing agents.
Later the rest of the deck will be poured on site.
Foster s lightweight yet strong open steel grid flooring is the answer for movable bridges or other conditions where minimizing dead load is a major consideration.
Common configurations shown in the design table can span up to about 15 feet but other wt main bar sizes can be used to achieve longer spans.
Over 380 000 sf of partial depth concrete filled steel grid deck which will be replaced in three stages.
A por tion of the grid extends up into the reinforced concrete slab making the two composite.
Concrete filled steel grid decks have been used in many major bridges such as the walt whitman bridge 1956 mackinac straits bridge 1957 verrazano narrows bridge 1964 and others.
Oldest of the seven toll facilities operated and maintained by the mdta.
Steel hybrid decks consist of an open grid deck and full depth precast deck panel.
Exodermic decks or unfilled steel grid decks composite with a reinforced concrete slab are the most structurally efficient grid deck systems available and offer increased span capacities and a slight weight advantage over half filled grid decks.
The most common cause of bridge deck distress is the corrosion of the reinforcing steel that results from the intrusion of chlorides into the concrete after repeated deicer applications.
The exodermic decks involve the same process as the partially filled grid decks except that a majority of the concrete is placed above the steel grid.
Decks open grid decks.
Unfilled steel grid typically 7 5 cm to 13 cm 3 to 5 2 deep with a 9 cm to 13 cm reinforced concrete slab on top of it.
Some of them have been in use for more than 60 years and have exhibited excellent performance characteristics.