Concrete-filled steel tubular column for high load carrying capacity and fire resistance

Patent metadata

Field	Value
Publication number	US-9677273-B2
Application number	US-201414554449-A
Country	US
Kind code	B2
Filing date	Nov 26, 2014
Priority date	Nov 26, 2014
Publication date	Jun 13, 2017
Grant date	Jun 13, 2017

Abstract

A concrete-filled steel tubular column for high load capacity, usually required in tall buildings, includes an outer longitudinally extending generally vertical tubular shell and an inner longitudinally extending perforated tubular steel shell disposed within said outer longitudinally extending vertical tubular shell and coaxial therewith. Further, a plurality of relatively small diameter vertically extending perforated tubular steel members are disposed around said inner longitudinally extending tubular shell between said outer longitudinally extending tubular steel shell and said inner longitudinally extending steel shell with axes parallel to said coaxial axes. The concrete-filled steel column wherein said inner steel shell is centrally disposed within the outer longitudinally extending vertical tubular steel shell and wherein the volume between the outer steel shell and the inner shell is filled with high strength concrete. The perforated inner shell and members have a plurality of meltable polymer plugs or caps on perforations to prevent plastic cement from flowing into or closing the openings during concreting. In the event of fire the plastic or polymer plugs or caps melt and allow gases and smoke to flow into the pipes and up through the inner member and out therefrom at the top of the column The inner vertical tubular shell and members may be subsequently used for injecting grout through the perforations (which get opened during fire by melting of polymer caps) for strengthening the post fire damaged concrete).

First claim

What is claimed is:

1. A concrete-filled steel column for high load carrying capacity consisting of:
an outer longitudinally extending generally vertical tubular shell and an inner longitudinally extending perforated steel tubular shell disposed within said outer longitudinally extending vertical tubular shell and coaxial therewith;
four inner vertically extending perforated tubular steel members disposed around said inner longitudinally extending tubular steel shell between said outer longitudinally extending tubular steel shell and said inner longitudinally extending steel shell with axes parallel to said coaxial axes and wherein the diameters of said tubular steel members are equal to or smaller than the diameter of said inner longitudinally perforated steel tubular shell;
a mass of cement filling said outer longitudinally extending generally vertical tubular shell and between said inner longitudinally extending perforated steel tubular shell and said outer longitudinally tubular shell;
a plurality of polymer caps for closing said perforations in said inner perforated tubular steel members and wherein said polymer caps are meltable in the event of an external fire to allow gases generated thereby to exit the column through the inner tubular members and out of the top of the column; and
in which said inner longitudinally extending generally vertical steel shell has a circular cross section; and
in which said circular cross section has a diameter of between about 300 mms to 1200 mms;
in which said outer longitudinally extending generally vertical tubular steel shell defines a circular cross sectional shape with a minimum diameter of about 500 mms and the inner shell having a minimum diameter of about 150 mm and each of said longitudinally extending steel tubular members each having a maximum diameter of about 150 mm; and
in which said mass of concrete is mixed with plastic fibers; and,
in which said inner longitudinally extending steel tubular shell includes a plurality of perforations therein for release of smoke and gases, emanating from the heating of concrete, through the inner steel shell and members to the outside at the top of said column; and,
which includes a cover and in which said inner steel shell and said steel members are covered at the top of said column such that the cover blows off due to the escape of gases during fire exposure; and,
in which the inner vertical tubular shell and members may be subsequently used for injecting grout through the perforations which get opened during fire by melting of polymer caps for strengthening the post fire damaged concrete.

Assignees

• Univ King Saud

Inventors

• Abbas Husain
• Al-Salloum Yousef A
• Almusallam Tarek H

Classifications

• E04C3/34 Primary

  of concrete other stone-like material, with or without permanent form elements, with or without internal or external reinforcement, e.g. metal coverings (E04C3/36 takes precedence) · CPC title

• E04C3/32

  of metal (E04C3/36 takes precedence) · CPC title

• E04B1/943 Primary

  elongated · CPC title

• E04C5/073

  Discrete reinforcing elements, e.g. fibres · CPC title

• E04B1/946

  Protection against smoke or toxic gases · CPC title