Page 22 - Wire Rope News & Sling Technology - October2019
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American suspension system. (Arnodin’s interview by the commission)

         French suspension system. (Arnodin’s interview by the commission)
         continued from page 20             same idea about “spinning” wire cable.  suspension  bridges. Ferdinand Arno-
         ing a windstorm. A new, much stiffer,   The anchoring rooms of the suspension   din, whose father had worked for Marc
         deck was installed. And later, Roebling   ropes were not inspectable, and were   Seguin, was very aware of Seguin’s
         added guy ropes among the suspenders.  embedded with lime (exactly identical to   cable and of the Seguin suspension
           This event gave credibility to the   those of the Basse-Chaine Bridge). John   bridges. He did the inspection and the
         Roebling theory regarding the stiffness   August Roebling was convinced that this   maintenance of these bridges.
         of the deck.                       was the proper solution. He applied for a   Ferdinand  Arnodin  created his  own
           These two men were competing for   patent in 1846. During his life he opposed   company for the construction  of sus-
         the construction of the railway suspen-  any inspections. Roebling died in 1869   pension bridges in 1872. He became in
         sion bridge over the Niagara River. The   during the construction of the Brooklyn   fact the unofficial successor of Marc Se-
         contract for the temporary bridge was   Bridge in New York, which would be   guin when he died in 1875.
         awarded to Ellet. But when Ellet and   completed by his son Washington. The   In 1870, the French  administration
         his client had a financial disagreement,   son didn’t agree with his father on that   of Ponts et Chaussées  mandated  that
         John August Roebling was awarded the   matter, and so he agreed that an inspec-  engineer Emile Malézieux make a sur-
         project. This bridge, with a span of 244   tion should be carried out. A summary   vey trip to the United States. In 1873
         m,  was  inaugurated  in  1854,  and  the   report of this inspection was published   Emile Malézieux  published  a report
         first  train,  weighting  200  T,  crossed   in 1881 by the engineer L. L. Buck, who   entitled, Travaux Publics des Etats-
         the bridge on March 18, 1855. Roebling   was in charge of that inspection. Buck   Unis d’Amérique en 1870. A section of
         did everything possible to increase the   clearly stated that the anchoring system   this  report  is  dedicated to  suspension
         stiffness of the bridge. It had a double   was facing the same problems as those   bridges and particularly to the railway
         deck – trains ran on the upper part, and   of the Basse-Chaine Bridge. Renovation   bridge over the Niagara River, which
         pedestrians and horse carriages crossed   was performed in 1887.      was built by John August Roebling in
         on the lower part. Thus, the dimensions   What might the destiny of suspen-  1855. The bridge is described with a lot
         and  the  geometry  gave  a  significant   sion  bridges have been, if the bridge   of  details. This  report  was  the  basis,
         stiffness  to  the  deck,  although  it  was   over the Niagara River had collapsed   the founding reference,  of the French
         initially made of wood. The suspenders   in  the  same manner  as the  Basse-  engineers, starting with Ferdinand Ar-
         joining the suspension  ropes  and the   Chaine Bridge?               nodin. It was used to establish the new
         deck were inclined, and additional un-  John August Roebling faced a big-  French school.
         der floor stays were also installed.  ger competition in the field of hoisting   The  bridge  configuration  with  sus-
           To fabricate the suspension ropes,   ropes. The English techniques had been   penders and inclined guy ropes con-
         Roebling used and patented the process   introduced in California by Andrew   necting the deck to the head of the piles
         imagined by Louis Vicat in 1831. In the   Smith. His son, under the name A. S.   is identified as John August Roebling’s
         report to the owner of the bridges, which   Hallidie, created a factory in California   suspension system. This is the “Ameri-
         was  published  in  1855,  Roebling  indi-  in  1857, where  he  produced ropes  for   can” suspension system.
         cated that the accident of the Wheeling   the gold mines and then for the cable   Engineer  Jollois,  who  designed the
         Bridge was the most critical that had   cars.  A. S. Hallidie is famous mainly   Saint Ilpize Bridge, imagined a sus-
         ever  occurred  on  a  suspension  bridge.   for his role in the development of the   pension system with a “French” stiffen-
         This proves that at that time Roebling   cable cars in San Francisco (1872).  ing beam. This is in fact the American
         was not aware of the Basse-Chaine                                     system, but without the addition of in-
         Bridge accident, and that he was not   HISTORY RESTARTS IN FRANCE,    clined guy ropes and suspenders.
         informed of what was happening in   WITH FERDINAND ARNODIN              The  engineer  Maurice  Levy devel-
         France. So it’s highly probable that he   It  was not until 1870  that  France   oped in-depth calculations  for that
         didn’t  copy  Vicat,  but  that  he  had  the   again authorized the construction  of   continued on page 24

         22     Wire Rope News & Sling Technology   October 2019
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