End anchors

Abstract

An improved structural reinforcement bar for use in poured concrete construction has an anchorage plate fixed to a rebar body through friction welding. The friction welded rebar body and anchorage plate result in a structural reinforcement bar with improved axially oriented tensile load transfer capabilities having minimal space requirements.

What is claimed is:  
     
         1 . In a reinforced concrete construction comprising a concrete structure and a reinforcing bar embedded therein; the improvement comprising; 
 an anchorage plate, and    a friction weld joining a surface of said anchorage plate to an end of said reinforcing bar.    
     
     
         2 . The construction of  claim 1  wherein said friction weld is an inertia weld.  
     
     
         3 . The construction of  claim 1  wherein said end of said reinforcing bar is enlarged.  
     
     
         4 . The construction of  claim 3  wherein said end of said reinforcing bar is enlarged by upset forging.  
     
     
         5 . The construction of  claim 1  wherein said anchorage plate is of lower strength than said reinforcing bar.  
     
     
         6 . The construction of  claim 1  wherein said anchorage plate is round.  
     
     
         7 . A reinforced concrete construction comprising a concrete structure, at least one reinforcing bar embedded in said concrete structure, said reinforcing bar having an end thereof enlarged by upset forging, a substantially round anchorage plate of lower strength than said reinforcing bar and a friction weld joining said enlarged end of said reinforcing bar to a surface of said anchorage plate.  
     
     
         8 . A method of manufacturing a structural reinforcement bar for embedding in poured concrete construction of the type having a rebar body extending between opposing first and second ends, comprising the steps of: 
 providing an anchorage plate;    inserting one of said anchorage plate and said body in a stationary collet;    inserting the other of said body and said anchorage plate in a rotationally driven collet with said first end of said body oriented toward said anchorage plate;    applying a rotational force to said rotationally driven collet until a desired rotational speed is reached;    applying an axial force to bring said first end of said body into contact with said anchorage plate;    removing said rotational force from said rotationally driven collet;    maintaining said axial force until said rotationally driven collet stops rotating and said body is fixed to said anchorage plate; and    removing said body and said anchorage plate from said driven collet and said stationary collet.    
     
     
         9 . A method of manufacturing for embedding in poured concrete construction a structural reinforcement bar of the type having a rebar body extending between opposing first and second ends, comprising the steps of: 
 forming an enlargement on a first end of a rebar body;    providing an anchorage plate;    inserting one of said anchorage plate and said body in a stationary collet;    inserting the other of said body and said anchorage plate in a rotationally driven collet with said enlarged end oriented toward said anchorage plate;    applying a rotational force to said rotationally driven collet until a desired rotational speed is reached;    removing said rotational force from said rotationally driven collet;    applying an axial force to bring said first end into contact with said anchorage plate;    maintaining said axial force until said rotationally driven collet stops rotating and said body is fixed to said anchorage plate; and    removing said body and said anchorage plate from said driven collet and said stationary collet.