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.

An assembly of concrete structural elements includes a first and a second concrete lower column, and a first and a second column capitals are supported on respective upper ends of the respective first and second lower columns. At least one inverted beam is extended between the first and second column capitals. At least one lower flat surface of the inverted beam is positioned on respective edges of the first and second column capitals.

An assembly of concrete structural elements includes a first and a second concrete lower column, and a first and a second column capitals are supported on respective upper ends of the respective first and second lower columns. At least one inverted beam is extended between the first and second column capitals. At least one lower flat surface of the inverted beam is positioned on respective edges of the first and second column capitals.

The present invention is a steel beam (10) having a steel profile (20) comprising a lower head (23) and an upper head (21) which is substantially parallel to said lower head (23), characterized by comprising cables (42) provided under the steel profile (23) along the length of the steel profile (20) and to which tensioning process is applied, and a lower reinforcing concrete (40) embodied by the steel profile (20) lower head (23) in the form of a layer in a manner covering the cables (42) so as to fix said cables (42) at their positions and tensions.

A panel assembly for a building includes a panel configured to extend between a first surface and a second surface. The panel is movable along a predetermined path relative to the first surface and the second surface. A first pin and a second pin are coupled to the panel. A first bottom face plate is positioned on a first side and defines a first slot. A second bottom face plate is positioned on a second side and defines a second slot. A first top face plate is positioned on the first side and defines a third slot. A second top face plate is positioned on the second side and defines a fourth slot. The first pin is movable in the first slot and the second slot, and the second pin is movable in the third slot and the fourth slot for guiding movement of the panel along the predetermined path.

A beam can comprise a plurality of steel channel members that extend along a longitudinal axis. The plurality of steel channel members can cooperate to define an interior volume that is configured to receive concrete therein. The plurality of steel channel members can comprise a first C-shaped channel member defining a channel therein and having first and second flanges. The channel of the first C-shaped channel member can define a portion of an outer boundary of the interior volume. The first and second flanges can extend into the interior volume. A plurality of internally projecting members can be spaced along the longitudinal axis. The plurality of internally projecting members can extend into the interior volume from a steel channel member of the plurality of steel channel members. A strap can extend across the interior volume so that when the interior volume is filled with concrete, the strap engages the concrete.

A beam can comprise a plurality of steel channel members that extend along a longitudinal axis. The plurality of steel channel members can cooperate to define an interior volume that is configured to receive concrete therein. The plurality of steel channel members can comprise a first C-shaped channel member defining a channel therein and having first and second flanges. The channel of the first C-shaped channel member can define a portion of an outer boundary of the interior volume. The first and second flanges can extend into the interior volume. A plurality of internally projecting members can be spaced along the longitudinal axis. The plurality of internally projecting members can extend into the interior volume from a steel channel member of the plurality of steel channel members. A strap can extend across the interior volume so that when the interior volume is filled with concrete, the strap engages the concrete.

Various implementations comprise methods and apparatuses for constructing a concrete structure. An apparatus according to one implementation includes a structure comprising a pre-cast concrete component that includes at least one post-tensioning duct, a post-tensioning tendon extending through the post-tensioning duct, and a poured in place concrete surface disposed above and coupled to the pre-cast concrete component.

Various implementations comprise methods and apparatuses for constructing a concrete structure. An apparatus according to one implementation includes a structure comprising a pre-cast concrete component that includes at least one post-tensioning duct, a post-tensioning tendon extending through the post-tensioning duct, and a poured in place concrete surface disposed above and coupled to the pre-cast concrete component.

A steel form is a steel form for forming a binding beam, including: a pair of Z-steels, wherein each of the pair of Z-steels is provided with a bottom plate portion and a side plate portion extending upward from the bottom plate portion, the bottom plate portion has a joining surface for joining the respective bottom plate portions of the pair of Z-steels to each other, and a groove portion allowing concrete placement is formed by the bottom plate portion and the side plate portion of each of the pair of Z-steels