Abstract: A voided floor panel is provided. The voided floor panel includes a pre-cast dome, strands, reinforcing bars, and a slab. The pre-cast dome includes a flange portion, stem portions, and joint portions. The strands are pre-tensioned. The reinforcing bars are inserted through rebar block-outs of the pre-cast dome. The joint portions, the strands, and the reinforcing bars are cast within the slab. The strands improve a resistance of the slab to flexure. The joint portions improve a vertical shear resistance between the slab and the pre-cast dome. The joint portions may include corrugated dovetails for further improving a horizontal shear resistance between the slab and the pre-cast dome.

Abstract: A voided floor panel is provided. The voided floor panel includes a pre-cast dome, strands, reinforcing bars, and a slab. The pre-cast dome includes a flange portion, stem portions, and joint portions. The strands are pre-tensioned. The reinforcing bars are inserted through rebar block-outs of the pre-cast dome. The joint portions, the strands, and the reinforcing bars are cast within the slab. The strands improve a resistance of the slab to flexure. The joint portions improve a vertical shear resistance between the slab and the pre-cast dome. The joint portions may include corrugated dovetails for further improving a horizontal shear resistance between the slab and the pre-cast dome.

Abstract: An ultra high performance concrete (UHPC) voided slab panel may include a top slab including a top skin and a bottom slab including a bottom skin. The top slab and the bottom slab may be joined at a joint filled with a joint material and positioned a select height within the UHPC voided slab panel. The top slab and the bottom slab may be joined via a connector assembly. The panel may include least two ribs defining at least one void accessible via at least one opening through an exterior surface of the UHPC voided slab panel. The UHPC voided slab panel may be fabricated from UHPC and a plurality of embedded prestressing strands, and may be configured to meet select strength requirements that are greater than select strength requirements for conventional precast concrete without reinforcing bars being embedded within the UHPC voided slab panel.

Abstract: A reusable lifting apparatus includes a first mount assembly embedded within a first layer of a concrete sandwich panel and a second mount assembly embedded within a second layer of a concrete sandwich panel. The reusable lifting apparatus includes a lifting insert insertable within a void in one or more insulation layers between the first layer and the second layer. The reusable lifting apparatus includes a lifting bolt couplable to at least one of the first mount assembly, the second mount assembly, or the lifting insert through a hole in the first layer. The lifting insert is pivotable within the void about an axis through the lifting bolt. The lifting insert and the lifting bolt are removable from the concrete sandwich panel so as to eliminate thermal bridging between the first layer and the second layer via the lifting insert and the lifting bolt.

Abstract: Flange-to-flange connectors and construction methods using such connectors are disclosed. The connector may include a first and second anchored plates secured to a first and second sets of anchoring bars. The connector may also include a first and second alignment plates configured to mate with the first and second anchored plates. The connector may further include at least one shim configured to be positioned between the first and second anchored plates. A bolt may be configured to secure the first and second alignment plates with the first and second anchored plates, respectively, and when the bolt is tightened, the bolt pulls the first and second alignment plates and the first and second anchored plates together to form a rigid connection, which may eliminate the need to form and cure concrete at job sites, allowing the time, cost, and construction complexity to be reduced significantly compared to conventional connection systems.

Abstract: Flange-to-flange connectors and construction methods using such connectors are disclosed. The connector may include a first and second anchored plates secured to a first and second sets of anchoring bars. The connector may also include a first and second alignment plates configured to mate with the first and second anchored plates. The connector may further include at least one shim configured to be positioned between the first and second anchored plates. A bolt may be configured to secure the first and second alignment plates with the first and second anchored plates, respectively, and when the bolt is tightened, the bolt pulls the first and second alignment plates and the first and second anchored plates together to form a rigid connection, which may eliminate the need to form and cure concrete at job sites, allowing the time, cost, and construction complexity to be reduced significantly compared to conventional connection systems.

Abstract: Methods and systems for constructing wind towers are disclosed. A wind tower may be constructed by vertically stacking and securing a plurality of modular units. Each modular unit of the plurality of modular units may include three generally hexagonal columns and three concrete panels coupled to the three generally hexagonal columns. The three concrete panels and the three generally hexagonal columns may jointly form a generally equilateral triangular prism.

Abstract: A pile splice section for a spliced prestressed concrete pile includes a prestressed concrete element including a first end and a second end and a plurality of tendons that extend from the first end to the second end. A first end assembly at the first end of the prestressed concrete element includes a first plate coupled to the plurality of tendons. The first end assembly further includes a plurality of internally threaded fasteners embedded in the first end of the prestressed concrete element that are engagable via apertures extending through the first plate. A second end assembly at the second end of the prestressed concrete element includes a second metal plate coupled to the plurality of tendons. The second end assembly further includes a plurality of apertures extending through the second plate and accessible via pockets proximate the second end of the prestressed concrete element.

Abstract: A pile splice section for a spliced prestressed concrete pile includes a prestressed concrete element including a first end and a second end and a plurality of tendons that extend from the first end to the second end. A first end assembly at the first end of the prestressed concrete element includes a first plate coupled to the plurality of tendons. The first end assembly further includes a plurality of internally threaded fasteners embedded in the first end of the prestressed concrete element that are engagable via apertures extending through the first plate. A second end assembly at the second end of the prestressed concrete element includes a second metal plate coupled to the plurality of tendons. The second end assembly further includes a plurality of apertures extending through the second plate and accessible via pockets proximate the second end of the prestressed concrete element.

Abstract: A lifting insert for a concrete sandwich panel is disclosed. The lifting insert includes a fiberglass rod and two end sleeves secured to two opposite ends of the fiberglass rod. The two end sleeves create confinement of fibers of the fiberglass rod to improve stress resistance of the fiberglass rod. The two end sleeves are also separated by a predetermined distance apart from each other to prevent/reduce thermal bridging. The lifting insert further includes two anchoring members secured to the two end sleeves for anchoring the fiberglass rod within the concrete sandwich panel.

Abstract: The present disclosure is directed to a concrete sandwich panel. The sandwich panel may comprise a first reinforced concrete panel; a second reinforced concrete panel; an insulating panel sandwiched between the first reinforced concrete panel and the second reinforced concrete panel; a tie comprising a generally triangle wave-shaped pattern having a period defined by peaks spaced at a regular interval and a peak-to-peak amplitude greater than the thickness of the insulating panel; wherein the insulating panel has a plurality of generally linear slots defined at the regular interval of the tie for receiving the tie such that opposing ends of the tie terminate adjacent to the insulating panel, and the plurality of generally linear slots are filled utilizing an insulating material upon insertion of the tie to reduce thermal bridging; and wherein the peaks of the tie mechanically join the first and second reinforced concrete panels to the insulating panel.

Abstract: The present disclosure is directed to a concrete sandwich panel. The sandwich panel may comprise a first reinforced concrete panel; a second reinforced concrete panel; an insulating panel sandwiched between the first reinforced concrete panel and the second reinforced concrete panel; a tie comprising a generally triangle wave-shaped pattern having a period defined by peaks spaced at a regular interval and a peak-to-peak amplitude greater than the thickness of the insulating panel; wherein the insulating panel has a plurality of generally linear slots defined at the regular interval of the tie for receiving the tie such that opposing ends of the tie terminate adjacent to the insulating panel, and the plurality of generally linear slots are filled utilizing an insulating material upon insertion of the tie to reduce thermal bridging; and wherein the peaks of the tie mechanically join the first and second reinforced concrete panels to the insulating panel.

Abstract: A pile splice section for a spliced prestressed concrete pile includes a prestressed concrete element including a first end and a second end and a plurality of tendons that extend from the first end to the second end. A first end assembly at the first end of the prestressed concrete element includes a first plate coupled to the plurality of tendons. The first end assembly further includes a plurality of internally threaded fasteners embedded in the first end of the prestressed concrete element that are engagable via apertures extending through the first plate. A second end assembly at the second end of the prestressed concrete element includes a second metal plate coupled to the plurality of tendons. The second end assembly further includes a plurality of apertures extending through the second plate and accessible via pockets proximate the second end of the prestressed concrete element.

Abstract: A precast post-tensioned segmental pole system capable of supporting a load is provided. The pole system includes a plurality of pole segments that use connectors and strands to anchor them together. The strands extend within a cavity formed in the pole segments and are external to the wall structure of the pole segments. The strands may be coupled between both of the pole segments, or be anchored to a connector. The connector includes an upper piece that is coupled to one pole segment, and a lower piece that is coupled to the other pole segment. Upper and lower pieces interlock with each other to join the pole segments to one another. The strands are placed in tension so that pole system is capable of withstanding forces imposed by the load.

Abstract: A prestressed concrete panel for a bridge construction includes a first section having at least one tension member extending therethrough. A second section of the panel is spaced from the first section to form a gap therebetween. The tension member extends through the second section also and across the gap. The gap is adapted to be aligned above a support beam or girder. At least one compression member also extends between the first and second sections and across the gap in such a manner such that the gap is maintained against the tension forces of the tension member.

Abstract: A precast post-tensioned segmental pole system capable of supporting a load is provided. The pole system includes a plurality of pole segments that use connectors and strands to anchor them together. The strands extend within a cavity formed in the pole segments and are external to the wall structure of the pole segments. The strands may be coupled between both of the pole segments, or be anchored to a connector. The connector includes an upper piece that is coupled to one pole segment, and a lower piece that is coupled to the other pole segment. Upper and lower pieces interlock with each other to join the pole segments to one another. The strands are placed in tension so that pole system is capable of withstanding forces imposed by the load.

Abstract: A tension member is provided for use in erecting structures that has an elongated body with an outer wall defining an inner space. A tendon extends from one end of the body to the other within the defined inner space. The tendon has a tension force placed upon it. Concrete material is added to the inner space to form a concrete holding member which surrounds the tendon and which is in turn surrounded by the outer wall. The concrete holding member thus contacts the tendon and, upon curing, maintains the tension force placed upon the tendon. The tension member is placed in compression when the tension force is released from the tendon. In another aspect of the present invention, an arch member is provided for use as a compression member in a bridge. The arch member has an elongated arcuate body with an outer wall defining an inner space. The inner space of the body is filled with a concrete so that the body provides support for the concrete.

Abstract: A precast, prestressed concrete joist having web openings through which mechanical and electrical equipment may pass. In an exemplary embodiment, the joist comprises generally horizontal opposite top and bottom concrete members with a concrete web interposed between them. This web may have openings through which mechanical and electrical equipment may pass. Prestress steel strands may extend lengthwise through both the top and bottom members to provide prestress in the concrete joist. The concrete joist may further comprise strand restraining devices for deflecting the prestress steel strands. The precast, prestressed concrete joist having a web opening may be constructed using a reusable casting apparatus. This casting apparatus comprises a prestressing bed onto which a frame may be mounted. The frame provides a means of applying tension to the prestress steel strands and of supporting prestress strand restraining devices.

Abstract: A precast, prestressed concrete joist having web openings through which mechanical and electrical equipment may pass. In an exemplary embodiment, the joist comprises generally horizontal opposite top and bottom concrete members with a concrete web interposed between them. This web may have openings through which mechanical and electrical equipment may pass. Prestress steel strands may extend lengthwise through both the top and bottom members to provide prestress in the concrete joist. The concrete joist may further comprise strand restraining devices for deflecting the prestress steel strands. The precast, prestressed concrete joist having a web opening may be constructed using a reusable casting apparatus. This casting apparatus comprises a prestressing bed onto which a frame may be mounted. The frame provides a means of applying tension to the prestress steel strands and of supporting prestress strand restraining devices.

Abstract: To erect concrete structures, precast concrete beams are formed, columns having void spaces therein are erected and angle irons are temporarily mounted to said columns at beam level wherein said beams may be temporarily supported. At least one beam is positioned orthogonal to a column near the void in the column supported by the angle iron and cast-in-place concrete fills the void between the ends of said beams and said columns. In another embodiment, the columns are solid and the beams have openings of such a size as to fit around the columns so that they can be lowered to the proper beam height about the column and fastened, with the other ends of the beam being joined to adjacent beams.