Method for strengthening or repairing an existing reinforced concrete structural element

Abstract

A method for strengthening an existing concrete column having a concrete body and a plurality of parallel longitudinal steel reinforcements includes the steps of preparing a steel wire cable that includes strands of steel filaments, winding the steel wire cable on the longitudinal steel reinforcements in a spiral manner relative to a centerline of the concrete body, fastening two opposite ends of the steel wire cable to the longitudinal steel reinforcements, and casting a structural material around the steel wire cable, the longitudinal steel reinforcements, and the concrete body.

We claim:  
     
         1 . A method for strengthening an existing reinforced concrete structural element that includes a concrete body extending in a longitudinal direction, and a plurality of parallel longitudinal steel reinforcements extending in the longitudinal direction and embedded in the concrete body, the concrete body having an inner portion surrounded by the steel reinforcements, and an outer portion surrounding the longitudinal steel reinforcements, the concrete body further having a segment with the outer portion removed in such a manner so as to expose the longitudinal steel reinforcements therefrom, the method comprising the steps of: 
 preparing a steel wire cable that includes strands of steel filaments;    winding the steel wire cable on the longitudinal steel reinforcements, which are exposed from the segment of the concrete body, in a spiral manner relative to a centerline of the concrete body under a predetermined amount of tension;    fastening two opposite ends of the steel wire cable to the longitudinal steel reinforcements; and    casting a structural material around the steel wire cable, the longitudinal steel reinforcements, and the inner portion of the segment of the concrete body.    
     
     
         2 . The method of  claim 1 , wherein each of the ends of the steel wire cable is formed into a loop that surrounds a selected one of the longitudinal steel reinforcements.  
     
     
         3 . The method of  claim 2 , wherein each of the ends of the steel wire cable is fastened to an adjacent end portion of the steel wire cable through a damper so as to form the loop.  
     
     
         4 . A method for strengthening an existing reinforced concrete structural element that has an outer surface, the method comprising the steps of: 
 disposing a plurality of parallel longitudinal steel reinforcements around the outer surface of the structural element;    preparing a steel wire cable that includes strands of steel filaments;    winding the steel wire cable on the longitudinal steel reinforcements in a spiral manner relative to a centerline of the structural element under a predetermined amount of tension;    fastening two opposite ends of the steel wire cable to the longitudinal steel reinforcements; and    casting a structural material around the steel wire cable, the longitudinal steel reinforcements, and the outer surface of the structural element.