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Mega-Bridge Construction

              Overcoming Multiple Mega-challenges

                                                     by Henry Vere
         In Northern Europe, the Baltic Sea converges with the North Sea at a body of
         water  known as the Øresund  Straits.  This wide stretch  of water  separates
         Denmark and Sweden. The Øresund Straits are also known for their notoriously
         wretched weather. But each shore also needed something that the other side
         had. Copenhagen lacked cheaper housing for its inadequate workforce, while
         Malmo in Sweden needed more jobs for its residents.

               onnecting the two cities of Copen-  at the  narrowest  point of  the sound,   development around the Øresund was
               hagen  and  Malmo  –  as  well  as   further  north  of  Copenhagen,  others   viewed as an answer to the intensify-
         Ctheir respective countries  –  had   for a more direct link from Copenhagen   ing globalization process and Sweden’s
         the potential to form an economic pow-  to Malmo. Additionally, some regional   decision to apply for membership of the
         erhouse; one large metropolis, connected   and local interests  argued that other   European Community.
         by a bridge. Making that dream a real-  bridge and road projects – notably the   Connecting the two largest cities
         ity proved an impossible chore, until the   unbuilt at that time Great Belt Fixed   of the region, which were both expe-
         technology  and  equipment  finally  ap-  Link – should take priority. The gov-  riencing  economic  difficulties,  stood
         peared within the past two decades.   ernments of Denmark  and Sweden   as another reason along with the im-
           The concept of a bridge over the Øre-  eventually signed an agreement to   proving communications to Kastrup
         sund  was  first  formally  proposed  in   build a fixed link in 1973.  Airport,  the  main  flight  transporta-
         1936 by  a  consortium  of  engineering   Ultimately, that project was cancelled   tion hub in the region.
         firms who proposed a national motor-  in 1978 due to the economic situation,   Those trying to figure out what would
         way network for Denmark. The idea   and growing environmental concerns.   work best eventually decided  on con-
         faded from discussion, for obvious rea-  As the economic situation improved in   structing the world’s longest cable-stay
         sons,  during  the  Second  World  War.   the 1980s, interest continued and a new   bridge. What has resulted is a bridge
         But was taken up again thereafter and   agreement was signed in 1991.  able to carry cars as well as the enor-
         studied in significant detail in various   An OMEGA  center  report identi-  mous weight of two-way rail on the
         Danish-Swedish  government commis-  fied  the  following  as  primary  motiva-  level  below  that of  the  vehicles  now
         sions through the 1950s and 60s.   tions for construction  of the bridge   crossing the Straits. This amounted to
           However, disagreement existed re-  included  improvement of transport   1,090 meters – 3,576 feet – of road and
         garding the placement and exact form   links  in northern  Europe and  beyond   rails run over a double deck that hangs
         of the link, with some arguing for a link   that, from Hamburg to Oslo. Regional   below 160 cables, while the surface of
                                                                                   the structure  stands 60 meters,
                                      The Øresund Bridge links Sweden and Denmark.  180 feet above the surface of the
                                      The bridge  is a combined  twin-track railway and dual   waters below.
                                      carriageway bridge-tunnel across the Øresund Strait.
                                      Photo © Per Björkdahl |         The  structure’s  support towers
                                                                                   soar over 600 feet into the sky,
                                                                                   making this one of the tallest ce-
                                                                                   ment structures  in  Sweden;  the
                                                                                   tower heights are equivalent to
                                                                                   that of a 60 story building. While
                                                                                   the  project  officially  started  in
                                                                                   1991, the challenges faced by no
                                                                                   means allowed those involved
                                                                                   with its construction  to have a
                                                                                   definite date for completion. Even
                                                                                   before work  began, the Danes
                                                                                   and Swedes agreed to unite their
                                                                                   country through a pact  proving
                                                                                   difficult to negotiate.
                                                                                     Companies from  both  nations
                                                                                   formed a consortium to build the
                                                                                   bridge together. The consortium’s
                                                                                   first  challenge  was  how  to  build
                                                                                   a 16  mile bridge.  Copenhagen’s
                                                                                   international airport lies on the
                                                                                   edge of the Danish shore. This fact
                                                                                                continued on page 10
         8      Wire Rope News & Sling Technology   April 2017
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