Method of reinforcing opening of steel frame girder

Abstract

A tube is inserted in an opening of a girder web. Grooves formed in edges of the opening are mated with grooves on the tube, and a pair of reinforcing plates are attached to the tube so as to sandwhich the girder web. An auxiliary force applicator is inserted in an axial force introduction hole of the reinforcing plates, and in a state where one reinforcing plate is fixed, a load is applied to the other reinforcing plate in the rotational axial force direction, and as it is rotated greater force is applied, and the girder web and the pair of reinforcing plates are friction grip connected. The auxiliary force applicators are pulled out from the axial force introduction holes and the axial holes are plug welded, further fixing the reinforcing plates and the girder web.

1 . A method of reinforcing an opening in a girder web comprising: 
 inserting a tube on which grooves are formed on the outer surface thereof in an opening provided in a girder web; and    mating grooves formed in edges of openings of at least one reinforcing body with the grooves of the tube so as to fix the girder web and the at least one reinforcing body.    
   
   
       2 . The method according to  claim 1 , wherein the at least one reinforcing body comprises a pair of reinforcing bodies, the girder web being sandwiched between the pair of reinforcing bodies.  
   
   
       3 . The method according to  claim 1 , wherein the girder web and the at least one reinforcing body are fixed by being friction grip connected.  
   
   
       4 . The method according to  claim 1 , further comprising partially welding the girder web and the at least one reinforcing body.  
   
   
       5 . The method according to  claim 1 , wherein rotational force is applied to axial force introduction holes provided in the at least one reinforcing body, thereby fixing the girder web and the at least one reinforcing body.  
   
   
       6 . The method according to  claim 5 , further comprising plug welding the axial force introduction holes, thereby weld fixing the at least one reinforcing body and the girder web.  
   
   
       7 . The method according to  claim 1 , further comprising further fixing the girder web and the at least one reinforcing body by bolts and nuts.  
   
   
       8 . The method according to  claim 4 , further comprising further fixing the girder web and the at least one reinforcing body by bolts and nuts.  
   
   
       9 . The method according to  claim 1 , further comprising mating the grooves of the tube with grooves formed on the inner surface of at least one sleeve tube.  
   
   
       10 . A method of reinforcing an opening in a girder web comprising: 
 inserting a tube in an opening provided in a girder web; and    fixing the girder web and at least one reinforcing body.    
   
   
       11 . The method according to  claim 10 , wherein the at least one reinforcing body comprises a pair of reinforcing bodies, the girder web being sandwiched between the pair of reinforcing bodies.