Tensioned construction beam and method therefor

Abstract

A tensioned construction beam comprises a main longitudinal body defining a beam length and opposite longitudinal ends. The main longitudinal body includes a tubular part extending along the beam length and defining a cavity therein that is circumscribed by an inner wall of this tubular part. One or more steel cables extend within the cavity along the beam length and are embedded therein via grout filling the cavity. The one or more steel cables have been submitted to a tension force prior to being embedded and released from this tension force such that the tension force is applied to the main longitudinal body.

What is claimed is: 
     
         1 . A tensioned construction beam comprising:
 a main longitudinal body defining a beam length and opposite longitudinal ends thereof, the main longitudinal body comprising a tubular part thereof extending along the beam length and defining a cavity therein circumscribed by an inner wall of the tubular part; and   one or more steel cables extending within the cavity along the beam length and embedded therein via grout, the one or more steel having been submitted to a tension force prior to being embedded and released from the tension force such that the tension force is applied to the main longitudinal body.   
     
     
         2 . A tensioned construction beam according to  claim 1 , wherein the tubular part defines open front and rear ends thereof, the one or more steel cables having an initial length exceeding the open front and rear ends and having been cut at the open front and rear ends for being released from the tension force when embedded in the tubular part of the beam. 
     
     
         3 . A tensioned construction beam according to  claim 1 , further comprising deviator elements positioned within the cavity and mounted to the inner wall for deviating the one or more steel cables at predetermined positions along the beam length. 
     
     
         4 . A tensioned construction beam according to  claim 3 , wherein the deviator elements are positioned above and/or below the one or more steel cables for engaging the one or more steel cables to respectively deviate them upwardly and/or downwardly at the predetermined positions along the beam length. 
     
     
         5 . A tensioned construction beam according to  claim 3 , wherein the deviator elements comprise plates having a width and length with holes defined therein along the width thereof, each of the holes receiving a respective one of the one of more steel cables therethrough, the holes being positioned along a predetermined height position of the plate to deviate the one or more steel cables upwardly or downwardly at the predetermined positions along the beam length. 
     
     
         6 . A method of making a tensioned construction beam comprising:
 providing a main longitudinal beam body defining a beam length and opposite longitudinal beam ends thereof, the main longitudinal body comprising a tubular part thereof extending along the beam length and defining a cavity therein circumscribed by an inner wall of the tubular part and respective open tube ends thereof;   positioning one or more steel cables within the cavity defining respective opposite cable ends thereof, the one or more steel cables extending along the beam length with the opposite cable end portions protruding outwardly of the cavity via respective ones of the open tube ends;   anchoring the one or more steel cables outside of the cavity;   stretching the one or more anchored steel cables against the anchoring thereof further outwardly of the cavity thereby applying a tension force to each of the one or more steel cables;   filling the cavity with grout thereby embedding the one or more steel cables under the tension force therein; and   cutting the two opposite cable end portions protruding outwardly of the one or more steel cables thereby releasing the embedded cable from the anchoring and from the stretching and thereby providing for the tension force applied to each of the one or more steel cables to be applied to the main longitudinal body.   
     
     
         7 . A method according to  claim 6 , wherein the anchoring of the one or more steel cables comprises anchoring at least one end portions protruding outwardly of the cavity at an anchoring point thereof. 
     
     
         8 . A method according to  claim 6 , wherein the anchoring of the one or more steel cables comprises anchoring the end portions protruding outwardly of the cavity at respective anchoring points thereof. 
     
     
         9 . A method according to  claim 8 , wherein one of the anchored end portions defines a free end thereof extending beyond the anchoring point, wherein the stretching comprises moving the free end further away from the cavity. 
     
     
         10 . A method according to  claim 6 , wherein the tension force applied to the main longitudinal body defines a camber at a position along the beam length, the method further comprising modulating the position of camber along the beam length. 
     
     
         11 . A method according to  claim 10 , wherein modulating comprises:
 positioning deviator elements in the cavity above and/or below of the one or more steel cables for engagement thereof at predetermined positions along the beam length prior to grouting to deviate the one or more steel cables upwardly and/or downwardly; and   mounting the deviator elements to the inner wall prior to grouting.   
     
     
         12 . A method according to  claim 10 , wherein modulating comprises;
 positioning deviator elements in the cavity, the deviator elements having holed to receive the one or more steel cables therethrough at predetermined positions along the beam length prior to grouting to deviate the one or more steel cables upwardly and/or downwardly; and   mounting the deviator elements to the inner wall prior to grouting.   
     
     
         13 . A system for tensioning a construction beam comprising a main longitudinal beam body defining a beam length and opposite longitudinal beam ends thereof, the main longitudinal body comprising a tubular part thereof extending along the beam length and defining a cavity therein circumscribed by an inner wall of the tubular part and respective open tube ends thereof, wherein one or more steel cables are positioned within the cavity defining respective opposite cable ends thereof, the one or more steel cables extending along the beam length with the opposite cable end portions protruding outwardly of the cavity via respective ones of the open tube ends;
 anchoring units for anchoring the cable end portions of the one or more steel cables and respective anchoring points thereof;   an actuator for moving free ends of the one or more steel cables extending outwardly of the anchoring points further away from the anchoring points to apply a tension force to each of the one or more steel cables; and   a cutter for cutting the two opposite cable end portions protruding outwardly of the one or more steel cables when embedded within the cavity via grout thereby releasing the embedded cable from the anchoring and from the stretching and thereby providing for the tension force applied to each of the one or more steel cables to be applied to the main longitudinal body.