David Wertz from the SC DOT has clued me in about the complexities of
connecting the final anchor beams - joining first the west approach with
the west deck and in about a month, the east approach with the east deck.
(Check out Closing the West Gap)
David said:
"Interestingly enough, neither one of the girders will actually be connected to the approach
span until possibly next week. As you probably noticed, the west end of the girder is
hanging a couple of feet lower than the approach girder. In order to get everything lined up
right, the rest of the steel on this segment will have to be placed, the net traveler will
have to be rolled onto this segment, the entire west tower deck will have to be "unjacked" back
toward the approach, the next pair of cables will have to be installed and partially tensioned,
additional tensioning will have to be done to the previous pair of cables, deck counterweights
will have to be moved, and deck panels will have to be placed. Then and only then will
all of the bolt holes be lined up perfectly to do the final bolt-up at the connection to the approach."
"To add a little detail to the "unjacking" that was mentioned, last week, the entire 1/4 mile long west
deck was jacked toward the channel about 3 1/2" using a few 200 ton hydraulic jacks to prepare for the
placement of the last two edge girders. The deck will have to be slowly and partially released back
to get the alignment just right for the final connection."
