Tower having a pre-stressed concrete column and construction method

Abstract

A hollow column having a wall surrounding an inner space is erected. Pre-stressing cables comprising tendons and two cable terminations are pre-assembled. Each tendon is contained in a respective jacket with a protective substance. Each cable termination comprises a block for anchoring each tendon of a pre-stressing cable, a chamber filled with a protective substance on a rear side of the block and a sealing system closing the chamber opposite the block. Each tendon of the pre-stressing cable extends through the sealing system and has its jacket interrupted in the chamber. The pre-assembled pre-stressing cables are installed in the inner space of the hollow column, with the two terminations of each cable bearing against abutment portions provided at the upper and lower parts of the column. The pre-stressing cables can then be tensioned.

1 . A method of building a tower, comprising:
 erecting a hollow column having a wall surrounding an inner space, with abutment portions provided at upper and lower parts of the column;   pre-assembling pre-stressing cables comprising tendons and two cable terminations, each tendon being contained in a respective jacket with a protective substance, each cable termination comprising a block for anchoring each tendon of a pre-stressing cable, a chamber filled with a protective substance on a rear side of said block and a sealing system closing the chamber opposite the block, each tendon of said pre-stressing cable extending through the sealing system and having its jacket interrupted in said chamber;   installing the pre-assembled pre-stressing cables in the inner space of the hollow column, the two terminations of each cable bearing against abutment portions at the upper and lower parts of the column; and   tensioning the pre-stressing cables.   
     
     
         2 . The method as claimed in  claim 1 , wherein each tendon includes a strand of metal wires lubricated mutually and with the jacket of the tendon by the protective substance, the jacket being coupled longitudinally with the strand so as to follow macroscopic deformations of the strand. 
     
     
         3 . The method as claimed in  claim 1 , wherein the protective substance contained in the jackets of the tendons is wax. 
     
     
         4 . The method as claimed in  claim 1 , wherein the protective substance contained in the chambers of the cable terminations is grease or wax. 
     
     
         5 . The method as claimed in  claim 1 , wherein the jackets of the tendons of a tensioned cable are exposed to the environment between the two terminations of said cable. 
     
     
         6 . The method as claimed in  claim 1 , wherein the tendons of a tensioned cable extend freely between the two terminations of said cable. 
     
     
         7 . The method as claimed in  claim 1 , wherein the installation of the pre-assembled pre-stressing cables comprises:
 lifting the cable to bring one of its terminations near an abutment portion located at the upper part of the column;   introducing the anchoring block of said termination through a hole provided in said abutment portion; and   connecting a ring to said anchoring block and applying said ring against the abutment portion around said hole.   
     
     
         8 . A tower comprising:
 a hollow column having a wall surrounding an inner space;   abutment portions located at upper and lower parts of the column; and   pre-stressing cables extending along the column in the inner space,   wherein each pre-stressing cable comprises at least one tendon and two cable terminations bearing against abutment portions at upper and lower parts of the column,   wherein each cable termination comprises an anchoring block, a chamber filled with grease or wax on a rear side of said block and a sealing system closing the chamber opposite the block,   each tendon being contained with wax as a protective substance in a respective jacket extending through the sealing system of a cable termination at each end of the tendon and interrupted in the chamber of said termination to let the tendon be held in the anchoring block.   
     
     
         9 . The tower as claimed in  claim 8 , wherein each tendon includes a strand of metal wires lubricated mutually and with the jacket of the tendon by the protective wax, the jacket being coupled longitudinally with the strand so as to follow macroscopic deformations of the strand. 
     
     
         10 . (canceled) 
     
     
         11 . The tower as claimed in  claim 8 , wherein the jackets of the tendons of a pre-stressing cable are exposed to the environment between the two terminations of said cable. 
     
     
         12 . The tower as claimed in  claim 8 , wherein the tendons of a pre-stressing cable extend freely between the two terminations of said cable. 
     
     
         13 . The tower as claimed in  claim 8 , wherein an abutment portion receiving a cable termination includes a hole having a cross-section larger than an outer cross-section of the anchoring block of said cable termination, the cable termination further comprising a ring connected to the anchoring block and applied against the abutment portion around said hole.