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continued from page 12             of the bearings were carried out by the   including motorway and railway con-
         King Carl XVI Gustaf as the host and   Swiss civil engineering firm Mageba.  nections on land, was expected in 2003,
         hostess of the ceremony.             Vibration issues,  caused  by several   to be recouped by 2037.  Incredibly,
           On June 12, 2000, two weeks before   cables in the bridge moving under cer-  the connection  will be entirely user-
         the dedication, 79,871  runners  com-  tain wind and temperature conditions,   financed. The owner company is owned
         peted in a half marathon from Amager,   were combatted with the installation of   half by the Danish state and half by the
         Denmark to Skane, Sweden. Although   compression  spring  dampers installed   Swedish  state. This  owner  company
         traffic between Denmark and Sweden   in pairs at the centre of the cables. Two   has taken loans guaranteed by the gov-
         increased by 61 percent in the first year   of these dampers were equipped with   ernments to finance the connection and
         after  the  bridge  opened,  traffic  levels   laser  gauges  for  ongoing  monitoring.   the user fees are its only income. After
         were not as high as expected, perhaps   Testing, development and installation   the  increase  in  traffic,  these  fees  are
         due to high tolls. However, since 2005,   of these spring dampers  was carried   enough  to  pay the  interest  and begin
         traffic levels have increased rapidly.   out by specialists European Springs.  repaying the loans,  which  is  expected
           This  may  be  due  to  Danes  buying   The  bridge  joins  Drogden  tunnel   to take about 30 years.
         homes in Sweden to take advantage   on  the  manmade  island,  Peberholm   Taxpayers have not paid for the
         of lower housing prices in Malmö and   or  Pepper  Islet.  Denmark  chose  the   bridge nor the tunnel, but tax money
         commuting to work  in Denmark.  In   name to complement the natural is-  has been used for the land connections.
         January 2016, amidst the  European   land of Saltholm or Salt Islet, just to   On  the  Danish  side,  the  land  con-
         migrant crisis, Sweden was granted a   the north. Peberholm is a designated   nection  has  domestic  benefit,  mainly
         temporary exemption from the Schen-  nature reserve built from Swedish   connecting the airport to the railway
         gen  Agreement in  order  to mandate   rock  and  the  soil  dredged  up  during   network. The Malmö City Tunnel has
         that all travelers across the bridge had   the  bridge  and  tunnel  construction,   the benefit of connecting the southern
         photographic  proof  of  identity.  A  fine   approximately 4 km (2.5 mi) long with   part of the inner city to the rail net-
         would be the punishment for travel   an average width of 500 m (1,640 ft). It   work and allowing many more trains
         companies serving  travelers without   is 20 m (66 ft) high.          to and from Malmö.
         such identity documents. This marked   The  connection  between  Peberholm   In the end, the construction came in
         a break with 60 years of passport-free   and the artificial peninsula at Kastrup   within the three billion dollar budget
         travel between the Nordic countries.  on Amager island, the nearest popu-  –  and  the  bridge-tunnel  was  finished
           At 7,845 m (25,738 ft), the bridge cov-  lated part of Denmark, is through the   three  months  ahead  of  schedule.  This
         ers half the distance between Sweden   13,287 foot-long Drogden Tunnel (Drog-  bridge has the tallest free-standing tow-
         and the Danish island of Amager, the   dentunnelen), comprises of an 11,516   ers in the world. Eventually, upon in-
         border between the two countries being   foot immersed tunnel plus 886-foot en-  spection it was noted that the bolts on
         5.3 km (3.3 mi) from the Swedish end.   try tunnels at each end. The tube tun-  the bridge’s guardrails were corroding.
         The structure  has a mass of 82,000   nel as described here in more detail was   This presented a clear danger in the
         tons and supports two railway tracks   made from 20 prefabricated reinforced   event of a traffic accident and the possi-
         beneath  four  road  lanes  in  a  horizon-  concrete segments – the largest in the   bility of vehicles plunging off the bridge
         tal girder extending along the entire   world at 55,000 tons each– intercon-  deck into the water below. The problem
         length of the bridge.              nected  in  a  trench  dug  in  the  seabed.   was solved by coating all the bolts and
           On both approaches to the three ca-  Two tubes in the tunnel carry railway   then  reattaching  them  better-fitting
         ble-stayed bridge sections, the girder is   tracks, two carry roads and a small fifth   washers.  Better to be safe than sor-
         supported every 140 m (459 ft) by con-  tube  is  provided  for  emergencies.  The   ry. Over 44 million people have now
         crete piers. The two pairs of free-stand-  tubes are arranged side–by–side.  crossed this ground-breaking engineer-
         ing cable-supporting towers are 204 m   The cost for the Øresund Connection,   ing and construction wonder. WRN
         (669  ft) high allowing shipping 57 m
         (187 ft) of head room under the main     Despite two schedule setbacks – the discovery of 16 unexploded World War II bombs
         span, but most ships’ captains prefer to   on the seafloor and an inadvertently skewed tunnel segment – the bridge-tunnel was
         pass through  the  unobstructed  Drog-                                   finished three months ahead of schedule.
         den Strait above the Drogden Tunnel.                                         Photo © Kim Carlson | Dreamstime.com
           The  cable-stayed main span is  491
         m  (1,611  ft)  long. A  girder  and  cable-
         stayed design  was  chosen  to  provide
         the specific rigidity necessary to carry
         heavy  rail  traffic,  and  also  to  resist
         large accumulations of ice. The bridge
         experiences  occasional  brief closures
         during  very severe  weather,  such  as
         the St. Jude storm, October 2013.
           Due to high longitudinal and trans-
         verse loads acting over the bridge and
         to accommodate movements between
         the superstructure and substructure, it
         has weighing up to 20 t each, capable of
         bearing vertical loads up to 96,000 kN
         in  a longitudinal direction  and up to
         40,000 kN in transverse direction. The
         design, manufacturing and installation

         14     Wire Rope News & Sling Technology   April 2017
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