Lynn Murphy (Project Coordinator)
At month 26 of the 36-month project:
Crews continue preparing the bridge deck for concrete:
Bridge Deck Drains
Drains spaced at engineered intervals are being installed where the drain gutter meets the concrete curb/sidewalk. This is time consuming work, as the recently installed deck rebar steel must be trimmed away to make room for the drainage structure, which must be set at the proper elevation.
Epoxy Coated Steel Rebar
A sub-contractor crew continues installing the 1.5 million pounds of steel rebar, creating a grid system across the bridge deck. The deck rebar work is currently about 90% complete (see photo).
Concrete Bridge Deck
In preparation for the bridge deck concrete pour, crews will be erecting a concrete screed machine (see the two sample photos from internet), which will extend across the entire width of the bridge deck. This machine must be built to very precise specifications, with several dry runs required to make sure it is running at the correct elevations. The screed machine rests on rails that will be installed on top of the outer most concrete forms. It uses augers to distribute the concrete mix, and then large floats will level and finish the concrete surface.
The contractor estimates that concrete pouring will begin in the next 4-5 weeks. Approximately 3,400 cubic yards of concrete will be pumped to create the nine-inch thick bridge deck. The finished concrete deck will be the driving surface for bridge traffic.
Note: The TDOT Lewallen Bridge Replacement Project began on Monday September 17, 2018 and is scheduled for completion on August 31, 2021
