Pre-assembly spiral stirrup

Abstract

The present invention relates to prefabricated shear reinforcement that is built in the interior of a slab around a column, more specifically to prefabricated shear reinforcement that is capable of having a plurality of bottom and top main bars whose one end extending into a column and a spiral stirrup bent continuously to form a plurality of rectangular shapes surrounding the bottom and top main bars, thereby having excellent fabrication, constructability, and space utilization, providing economical advantages, minimizing labors needed on a construction site, and reducing a period of construction.

1 . Prefabricated shear reinforcement, which is built in the interior of a slab ( 1 ) around a column ( 2 ), comprising:
 a plurality of bottom main bars ( 4 ) located on the bottom of the interior of the slab ( 1 ) in such a way as to allow one end to extend to the interior of the column ( 2 );   a plurality of top main bars ( 5 ) located on the top of the interior of the slab ( 1 ) in a parallel relation with the plurality of bottom main bars ( 4 ) in such a way as to allow one end to extend to the interior of the column ( 2 ); and   a spiral stirrup ( 6 ) bent continuously to form a plurality of rectangular shapes to surround the plurality of bottom main bars ( 4 ) and the plurality of top main bars ( 5 ).   
     
     
         2 . The prefabricated shear reinforcement according to  claim 1 , wherein the spiral stirrup ( 6 ) consists of a plurality of planar constraint portions ( 61 ) bent to surround the bottom and top main bars ( 4  and  5 ) on the same plane perpendicular to the bottom and top main bars ( 4  and  5 ) and connection portions ( 62 ) each connecting the neighboring planar constraint portions ( 61 ) to one another. 
     
     
         3 . The prefabricated shear reinforcement according to  claim 2 , wherein four top main bars ( 5 ) and four bottom main bars ( 4 ) are provided, and a pair of spiral stirrups ( 6 ) is provided, so that each planar constraint portion ( 61 ) surrounds the two top main bars ( 5 ) and the two bottom main bars ( 4 ). 
     
     
         4 . The prefabricated shear reinforcement according to  claim 2 , wherein three top main bars ( 5 ) and three bottom main bars ( 4 ) are provided, and each planar constraint portion of the spiral stirrup is bent to surround the four top and bottom main bars ( 5  and  4 ) located on both outermost sides thereof and the remaining one top main bar ( 5 ) and the remaining one bottom main bar ( 4 ) located on the central portion thereof, sequentially. 
     
     
         5 . The prefabricated shear reinforcement according to  claim 2 , wherein four top main bars ( 5 ) and four bottom main bars ( 4 ) are provided, and each planar constraint portion ( 61 ) of the spiral stirrup ( 6 ) is bent to the shapes of two rectangles whose central portions overlapping each other. 
     
     
         6 . The prefabricated shear reinforcement according to  claim 1 , further comprising a pair of braces ( 60 ) coupled to both side surfaces thereof, respectively, in such a way as to cross each other in a diagonal direction. 
     
     
         7 . The prefabricated shear reinforcement according to  claim 1 , wherein the bottom main bars ( 4 ) are coupled to a fixing plate ( 7 ) to which the end portions of the bottom main bars ( 4 ) of the prefabricated shear reinforcement in the opposite side to the column ( 2 ) are coupled. 
     
     
         8 . The prefabricated shear reinforcement according to  claim 1 , further comprising a spacer ( 8 ) located adjustable in height on the undersides of the neighboring bottom main bars ( 4 ). 
     
     
         9 . The prefabricated shear reinforcement according to  claim 8 , wherein the spacer ( 8 ) has a roller ( 83 ) adapted to move the prefabricated shear reinforcement. 
     
     
         10 . The prefabricated shear reinforcement according to  claim 9 , wherein the spacer ( 8 ) comprises a support ( 81 ) consisting of a horizontal connection portion ( 811 ) transversing the neighboring bottom main bars ( 4 ), a first vertical portion ( 812 ) bent vertically downward from one end of the horizontal connection portion ( 811 ), a horizontal support portion ( 813 ) bent vertically from the other end of the horizontal connection portion ( 811 ) in parallel with the bottom main bars ( 4 ), and a second vertical portion ( 814 ) bent vertically downward from the outside end portion of the horizontal support portion ( 813 ), a leveler ( 82 ) coupled adjustable in height to the underside of any one of the first vertical portion ( 812 ) and the second vertical portion ( 814 ) of the support ( 81 ), and the roller ( 83 ) detachably coupled to the underside of the other of the first vertical portion ( 812 ) and the second vertical portion ( 814 ).