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Wire Rope Vital in

                    Construction of One of the

                         World’s Widest Bridges

                                                 by Peter Hildebrandt
         Hard  to believe  stands  the fact that  the bridge  – now known as the original
         Tappan Zee Bridge – first cantilevered out over nearly the widest point in the
         Hudson River, all the way back in 1952-1955. At three miles in length the structure
         spans the Hudson at its second-widest point. And perhaps, for all those Jeopardy
         enthusiasts  out there, the  Hudson  River actually  flows two ways, making  this
         water body as much inland estuary as river.

              he strange-sounding crossing re-  A  report  was  issued  by  the  Federal   state passed legislation freezing the
              ceived its name in the 1600s. Area   Highway Administration in October,   toll on the bridge at $5 through 2020 in
         TDutch settlers combined both dif-  2011, designating the Tappan Zee’s re-  its 2016 legislative session.
         ferent cultures  and words. “Tappan”   placement to be a dual-span twin bridge.   The new Tappan Zee Bridge was pro-
         may  have been regional natives and   The  new  bridge  has  now  been  under   posed to include four vehicle lanes on
         the Old World “zee” for sea, resulting   construction  a  few  yards  to  the  north   each  span,  for  a total of  eight  lanes,
         in a bridge name mistaken by baffled   of the existing bridge, and will connect   as well  as a shared-use  bicycle  and
         generations of car-bound children  as   to the existing highway approaches of   pedestrian path. Like its predecessor,
         one named for the familiar primate –   the  New  York  State  Thruway  –  I-87   the new Tappan Zee Bridge will be ad-
         the chimpanzee.                    as well as I-287 – on both river banks.   ministered by the NY State Thruway
           The Tappan Zee Bridge, as well as   Construction began as scheduled dur-  Authority, same as before.
         the nearby smaller crossing, the Bear   ing 2013, with completion targeted for   New York’s  Metropolitan Transpor-
         Mountain Bridge stand as the only   2017. The project now has an estimated   tation Council  added  the Tappan Zee
         crossings  of this 33-mile section of   completion date of April 2018 at a cost of   Bridge to its list of projects eligible for
         river that passes through the City  of   $3.98 billion dollars.       federal  funding  in  August,  2012.  U.S.
         New York’s thickly settled northern   Originally, it was thought that   DOT approved the plan in late Septem-
         suburbs.  But  when  the  bridge  first   bridge tolls could more than double,   ber, 2012  with the approval  process
         opened  up  traffics  amounts  would  be   to $12-$15 for automobiles, eastbound   actually taking fewer than 10 months
         considered today as downright antique   only, rising to those of New York City’s   as opposed to the traditional multi-
         compared to  what  the  deteriorating   Hudson River crossings. However, the          continued on next page
         current structure bears – an average of
         138,000 vehicles per day and substan-  The I Lift NY super crane is prepared to install additional girders for the new bridge’s Rockland
         tially more than its designed capacity.   approach. Photo taken July 2015. All Photos: New York State Thruway Authority.
           During its first decade, the bridge car-
         ried fewer than 40,000 vehicles per day.
         Part of the explanation for replacing the
         bridge stems from construction in  the
         wake  of  the  Korean  conflict,  requiring
         a  budget  of  a  minuscule  $81  million.
         Unlike other major bridges in the New
         York area, the Tappan Zee Bridge was
         designed to last just 50 years. This new
         bridge is intended to remain structur-
         ally sound some 100 years.
           In 2007, Minnesota’s  I-35W Missis-
         sippi River bridge collapsed, raising
         fears  about the Tappan Zee  Bridge’s
         structural  integrity. These  concerns,
         together  with  traffic  overcapacity
         and increased  maintenance costs,  in-
         creased the earnest communications
         already ongoing  about replacing  the
         Tappan Zee with either a tunnel or a
         new bridge. Six options were identified
         and submitted for project study and en-
         vironmental review.
         8      Wire Rope News & Sling Technology   February 2017
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