Non-welding type concrete-filled steel tube column having slot and method for fabricating the same

Abstract

A non-welding type concrete-filled steel tube column utilizing a slot, in which an external steel tube is bended and retracted to allow a jointing portion thereof to be formed as a T-shaped bending part is provided. A slot is inserted into the T-shaped bending part in a sliding manner to construct in a non-welding manner, and a multi-perforated penetrating part can be formed on the external steel tube to secure fire resistance capacity thereof. A method of fabricating the same is also provided.

What is claimed is: 
     
         1 . A concrete-filled steel tube column (CFT), comprising;
 an external steel tube formed of an integrated steel plate and is bended and retracted to allow a jointing portion of both end faces thereof to be formed as a T-shaped bending part, the external steel tube having a multi-perforated penetrating part formed thereon;   a slot having a shape corresponding to the shape of the T-shaped bending part to allow the T-shaped bending part to be inserted thereinto; and   concrete placed and cured in the external steel tube in a state where the T-shaped bending part is inserted into the slot;   wherein the external steel tube is jointed by the slot in a non-welding manner.   
     
     
         2 . The non-welding type concrete-filled steel tube column utilizing a slot of  claim 1 , wherein the slot has a ‘ ’ shape corresponding to the T-shaped bending part. 
     
     
         3 . The non-welding type concrete-filled steel tube column utilizing a slot of  claim 2 , wherein the ‘ ’ shaped slot is slid along and coupled to the T-shaped bending part to allow the external steel tube to be integrated in a non-welding manner. 
     
     
         4 . The non-welding type concrete-filled steel tube column utilizing a slot of  claim 3 , further comprising a ‘ ’′-shaped restricting steel fitting coupled to a remaining end portion of the T-shaped bending part, which is not inserted into the ‘ ’-shaped slot. 
     
     
         5 . The non-welding type concrete-filled steel tube column utilizing a slot of  claim 1 , wherein the multi-perforated penetrating part of the external steel tube discharges steam pressure generated in the concrete in fire. 
     
     
         6 . A method of fabricating a concrete-filled steel tube column (CFT), comprising the steps of;
 a) forming a multi-perforated penetrating part on an integrated external steel tube;   b) bending and retracting the external steel tube to allow a jointing portion of both end faces of the external steel tube to be formed as a T-shaped bending part;   c) fabricating a slot having a shape corresponding to the shape of the T-shaped bending part;   d) inserting the T-shaped bending part into the slot to allow the external steel tube to be joined by the slot in a non-welding process; and   e) placing and curing concrete in the external steel tube in a state where the T-shaped bending part is inserted into the slot.   
     
     
         7 . The method of fabricating the non-welding type concrete-filled steel tube column utilizing a slot of  claim 6 , wherein the slot in step c) has a ‘ ’ shape corresponding to the T-shaped bending part. 
     
     
         8 . The method of fabricating the non-welding type concrete-filled steel tube column utilizing a slot of  claim 7 , wherein the ‘ ’ shaped slot is slid along and coupled to the T-shaped bending part to allow the external steel tube to be integrated in a non-welding manner. 
     
     
         9 . The method of fabricating the non-welding type concrete-filled steel tube column utilizing a slot of  claim 8 , further comprising the step of fabricating a ‘ ’′-shaped restricting steel fitting, and coupling the ‘ ’′-shaped restricting steel fitting to a remaining end portion of the T-shaped bending part, which is not inserted into the ‘ ’-shaped slot, between step d) and step e). 
     
     
         10 . The method of fabricating the non-welding type concrete-filled steel tube column utilizing a slot of  claim 6 , wherein the multi-perforated penetrating part of the external steel tube in step a) discharges steam pressure generated in the concrete in fire.