Palmetto Bridge Constructors crews have
completed two test shafts on the $531 million design/build project in Charleston.
They have driven four casings for drilled shafts and are dredging on the
west pier of the main span.
A 4200 series 3 ringer crane has been mobilized, and will be used to set
the huge 230-foot long, 10-foot diameter rebar cages for the drilled shafts
under the towers for the cable-stayed bridge. They will be using a tilting
frame to assist with standing the unwieldy rebar cage without deforming
the shape. The rebar cage must be set in one piece because commercial shipping
traffic and tide fluctuations of five to seven feet give crews a limited
number of hours to drill a hole and fill it with concrete, leaving no time
for splicing.
On both sides of the main span, crews will be building high level, structural
steel approaches. They will also be constructing three-level interchanges
with prestressed concrete on either side of the main span. On the Charleston
side, the interchange will tie into I-26, and on the Mt. Pleasant side,
it will tie into U. S. 17. Both interchanges will feature two flyover bridges.
Construction began on July 16, 2001, and is slated for completion in March
2005. |
 A
large crane lifts one of the 230-foot long, 10-foot diameter cages of reinforcing
steel for a drilled shaft supporting the foundation of the cable-stayed
bridge. The lifting beam at the top stabilizes the rebar cage.
This five-foot-diameter drilling bucket is making a test shaft. The old
bridge over the Cooper River shows in the background. |