Abstract: A modular structure construction and repair system for use in new bridge construction and old bridge repair. The invention comprises a plurality of prefabricated modules which have a plurality of longitudinally extending beams and deck portions molded thereto. The modules are positioned over a plurality of girders so that longitudinal joints are formed above the girder. In the repair of an old bridge, an old section of the bridge deck is removed, and the modules are positioned on the existing girders. The modules are attached to the girders such that a shear connection is provided therebetween. Precompression may also be applied to clamp the sides of adjacent deck portions together. Various embodiments disclose this precompression and the shear connections.

Abstract: A composite structural member with pre-compression assembly. The apparatus comprises a plurality of longitudinally extending composite units. Each composite unit comprises a plurality of longitudinally extending girders or beams disposed on the bridge supports and a deck portion made of a moldable material and attached to the beams. Pre-compression is used for clamping adjacent units together such that a gap or hardened grout-filled joint between the deck portions thereof is substantially closed. The pre-compression portion of the apparatus includes a threaded member disposed through holes in facing beams of adjacent composite units with a fastener engaging the threaded member so that tightening of the fastener on the threaded member pulls the adjacent units together. The deck portions of the composite units may use a tongue-in-groove construction, and adhesive may be placed in the gap between the deck portions.

Abstract: A composite structural member with a longitudinally extending structural haunch. The composite structural member comprises a plurality of longitudinally extending girders with molded sections disposed thereon. The molded section comprises a molded deck portion having a plurality of longitudinally extending structural haunches extending downwardly therefrom. Each haunch is disposed on a corresponding girder. The haunches are molded around shear connectors attached to the girders. The resulting structure has greater strength properties than a corresponding prior art structure having no haunch, the same deck thickness and substantially the same overall height and girder weight.

Abstract: A composite structural member with a thin deck portion. The composite structural member comprises a plurality of longitudinally extending girders with a plurality of composite members disposed thereon. The composite structural member comprises a plurality of transversely extending beams with a molded deck structure thereon. In one embodiment, the composite member is a prefabricated composite unit which is installed on the girders and attached thereto. In a second embodiment, the beams are positioned on the girders, and the deck portion is poured in place. In both embodiments, the molded deck portion is substantially thinner than for the prior art structures, but the present invention has greater strength characteristics. A preferred thickness of the deck portion is in the range of about 4 inches to less than about 6.5 inches, with a preferred thickness of five inches. The thickness of the deck portion is such that a single layer of reinforcing material may be used.

Abstract: A composite, prestressed structural member and methods of forming such a member. The apparatus includes a plurality of longitudinally extending girders and a deck unit attached thereto. The deck unit may comprise a plurality of adjacent composite units disposed on the girders, with each composite unit having a plurality of beams with a molded deck portion formed thereabove. In one method, the structure is formed by positioning the girders on a construction support adjacent to a center portion of the girders such that the free ends of the girders cantilever and deflect downwardly. The beams of the composite units are attached to the girders in this construction position. In a second method, the structure is formed by positioning the girders in their normal operating position such that they are supported on opposite ends, and then providing a support for a center portion of the girders such that at least a portion of the lower edges of the girders are placed in compression.

Abstract: A composite, prestressed structural member, such as a bridge unit and methods of forming such a member. The apparatus includes a plurality of longitudinally extending girders which are transversely spaced and a plurality of adjacent composite units disposed on the girders. Each composite unit has a plurality of beams with a molded deck portion formed thereabove. The beams are positioned transversely with respect to the girders and attached thereto. Additional, longitudinal beams are disposed between the transversely extending beams over the girders. The longitudinal beams are attached to the girders and by connectors to the molded deck. The structure is formed by positioning the girders on a construction support adjacent to a center portion of the girders such that the free ends of the girders cantilever and deflect downwardly. The beams of the composite units are attached to the girders in this construction position. Any gaps between adjacent composite units are filled with a non-shrink, high strength grout.

Abstract: A composite, prestressed structural member, such as a bridge unit and methods of forming such a member. The apparatus includes a plurality of longitudinally extending girders which are transversely spaced and a plurality of adjacent composite units disposed on the girders. Each composite unit has a plurality of beams with a molded deck portion formed thereabove. The beams are positioned transversely with respect to the girders and attached thereto. Additional, longitudinal beams are disposed between the transversely extending beams over the girders. The longitudinal beams are attached to the girders and by connectors to the molded deck. The structure is formed by positioning the girders on a construction support adjacent to a center portion of the girders such that the free ends of the girders cantilever and deflect downwardly. The beams of the composite units are attached to the girders in this construction position. Any gaps between adjacent composite units are filled with a non-shrink, high strength grout.

Abstract: A composite, prestressed structural member, such as a bridge unit and methods of forming such a member. The apparatus includes a plurality of longitudinally extending girders which are transversely spaced and a plurality of adjacent composite units disposed on the girders. Each composite unit has a plurality of beams with a molded deck portion formed thereabove. The beams are positioned transversely with respect to the girders and attached thereto. Additional, longitudinal beams are disposed between the transversely extending beams over the girders. The longitudinal beams are attached to the girders and by connectors to the molded deck. The structure is formed by positioning the girders on a construction support adjacent to a center portion of the girders such that the free ends of the girders cantilever and deflect downwardly. The beams of the composite units are attached to the girders in this construction position. Any gaps between adjacent composite units are filled with a non-shrink, high strength grout.

Abstract: A composite, pre-stressed structural member comprised of concrete and a lower metal support member, and method for forming and pre-stressing the same. The metal support member and a concrete mold are connected for parallel deflection with the support member uppermost and shear-connectors extending into the mold. The connected mold and support member are supported for deflection and concrete is poured into the mold and allowed to harden. During hardening of the concrete the mold and support member are deflected by the weight of the concrete, mold and support member, pre-stressing the support member. Upon hardening of the concrete and inverting to a concrete-uppermost position, a composite, pre-stressed structural member is provided.

Abstract: An improved composite, pre-stressed structural member and method of forming such a member of the type provided by upside down forming which includes connecting the steel beams of the composite member to the upper side of a mold so that a parallel deflection of the mold and beams occurs as the mold is filled with concrete. The improvement comprises utilizing a steel beam having a flange at or near the neutral axis with respect to a vertical deflection of the support member. After the composite structure is formed, the flange is away from the neutral axis with respect to a vertical deflection of the composite structure. This flange, therefore, significantly increases the section modulus of the composite structure while not adding significantly to the resistance to bending of the beam during pre-stressing. Stacked and welded I-beams are an example of a support in accordance wth this invention.

Abstract: A composite, pre-stressed structural member comprised of concrete and a lower metal support member, and method for forming and pre-stressing the same. The metal support member and a concrete mold are connected for parallel deflection with the support member uppermost and shear-connectors extending into the mold. The connected mold and support member are supported for deflection and concrete is poured into the mold and allowed to harden. During hardening of the concrete the mold and support member are deflected by the weight of the concrete, mold and support member, pre-stressing the support member. Upon hardening of the concrete and inverting to a concrete-uppermost position, a composite, pre-stressed structural member is provided.