A concrete fillable steel joist includes a generally U-shaped member and a top chord. The generally U-shaped member has spaced apart webs and a bottom chord. The top chord is operably attached to the U-shaped member. The top chord has a plurality of spaced apart top chord holes. The U-shaped member and the top chord define a volume that is fillable with concrete when opposed ends of the U-shaped member have joist ends operably attached thereto. The joist ends may be a pair of end plates. Alternatively, the joist ends may be structural members. A concrete fillable steel joist system includes a plurality of spaced apart concrete fillable steel joists, and metal decking. The metal decking is operably attached between the spaced apart steel joists. The concrete fillable steel joist and the metal decking are configured to receive concrete.

A lightweight concrete nailer form preferably includes a semi-tubular member and a plurality of cross members. The semi-tubular member includes a bottom wall, a first sidewall, a second sidewall, a first upper flange and a second upper flange. A height of the first and second sidewalls may also increase over a length of the semi-tubular member to form a tapered semi-tubular member. A plurality of openings are preferably formed through the bottom wall and the first side wall for the flow of lightweight concrete. The cross member preferably includes a bottom flange, an upright member and a top flange. An opening is formed through the upright member for the flow of lightweight concrete. The plurality of cross members fit inside the semi-tubular member. The semi-tubular member may be stacked with a second semi-tubular member. A cover plate may be attached to a top of the semi-tubular member.

A lightweight concrete nailer form preferably includes a semi-tubular member and a plurality of cross members. The semi-tubular member includes a bottom wall, a first sidewall, a second sidewall, a first upper flange and a second upper flange. A height of the first and second sidewalls may also increase over a length of the semi-tubular member to form a tapered semi-tubular member. A plurality of openings are preferably formed through the bottom wall and the first side wall for the flow of lightweight concrete. The cross member preferably includes a bottom flange, an upright member and a top flange. An opening is formed through the upright member for the flow of lightweight concrete. The plurality of cross members fit inside the semi-tubular member. The semi-tubular member may be stacked with a second semi-tubular member. A cover plate may be attached to a top of the semi-tubular member.

A support column extends in a longitudinal dimension and includes a plurality of outer hollow longitudinal structures. Each longitudinal structure defines an interior passage extending along a length of the longitudinal structure. The support column includes a plurality of inner members. The plurality of outer hollow longitudinal structures are aligned end-to-end along a single axis. The interior passages of the plurality of outer hollow longitudinal structures cooperate to define an interior passage of the support column. The inner members are aligned end-to-end along the single axis within the interior passage of the support column so that opposed longitudinal ends of each of the inner members extend to respective longitudinal ends of each adjacent inner member. At least one end of at least one inner member is longitudinally offset from every longitudinal end of the plurality of outer hollow longitudinal structures.

A support column extends in a longitudinal dimension and includes a plurality of outer hollow longitudinal structures. Each longitudinal structure defines an interior passage extending along a length of the longitudinal structure. The support column includes a plurality of inner members. The plurality of outer hollow longitudinal structures are aligned end-to-end along a single axis. The interior passages of the plurality of outer hollow longitudinal structures cooperate to define an interior passage of the support column. The inner members are aligned end-to-end along the single axis within the interior passage of the support column so that opposed longitudinal ends of each of the inner members extend to respective longitudinal ends of each adjacent inner member. At least one end of at least one inner member is longitudinally offset from every longitudinal end of the plurality of outer hollow longitudinal structures.

The present invention relates to a concrete structure for constructing a building floor and a building floor construction structure including the same. The present invention provides a concrete structure for constructing a building floor which forms a building floor foundation, including: a concrete main body to store fire-extinguishing water for fire suppression; and a fire-extinguishing water injection unit to inject the fire-extinguishing water stored in the concrete main body, and a building floor construction structure including the same. According to the present invention, the concrete structure for forming a building floor stores fire-extinguishing water, and thus early fire suppression is possible, building floor construction is facilitated, and excellent inter-floor sound insulation properties are provided.

The present invention relates to a concrete structure for constructing a building floor and a building floor construction structure including the same. The present invention provides a concrete structure for constructing a building floor which forms a building floor foundation, including: a concrete main body to store fire-extinguishing water for fire suppression; and a fire-extinguishing water injection unit to inject the fire-extinguishing water stored in the concrete main body, and a building floor construction structure including the same. According to the present invention, the concrete structure for forming a building floor stores fire-extinguishing water, and thus early fire suppression is possible, building floor construction is facilitated, and excellent inter-floor sound insulation properties are provided.

A self-aligning corner bead for fireproofing structural steel, having a strip of welded wire fabric cut to the appropriate width for the fireproofing thickness and bent longitudinally to form an obtuse V-shaped device is disclosed. A plastic nosing is installed along one edge. A method of finishing the corners for fireproofing of structural steel member using an improved corner bead includes the step of attaching the first wing of an obtuse V-shaped device through a lathe to the structural steel member utilizing pneumatic or screw type fasteners. The mesh structure of the second wing of the V-shaped device provides a dam to form a roughened surface on the first application of fireproofing material until it hardens.

A self-aligning corner bead for fireproofing structural steel, having a strip of welded wire fabric cut to the appropriate width for the fireproofing thickness and bent longitudinally to form an obtuse V-shaped device is disclosed. A plastic nosing is installed along one edge. A method of finishing the corners for fireproofing of structural steel member using an improved corner bead includes the step of attaching the first wing of an obtuse V-shaped device through a lathe to the structural steel member utilizing pneumatic or screw type fasteners. The mesh structure of the second wing of the V-shaped device provides a dam to form a roughened surface on the first application of fireproofing material until it hardens.

Provided are a hollow composite beam using a dual-web and a construction method thereof. The hollow composite beam using a dual-web can secure space efficiency using a tendon installed in an internal space of a dual-web and can efficiently adjust a tensioning force using the tendon anchored by an anchoring wedge and a separable bolt, wherein the dual-web is formed as a web of a steel beam having a bottom flange on which a deck plate is supported.