Prestressed composite girder, continuous prestressed composite girder structure and methods of fabricating and connecting the same

A method of fabricating a prestressed composite girder, comprising:

• arranging shear reinforcing bars and main reinforcing bars across the prestressed composite girder;
• arranging sheaths containing steel wires across the prestressed composite girder;
• placing sole plates on ends of the prestressed composite girder;
• arranging steel plates provided with shear connecting members in upper and lower flanges of the prestressed composite girder;
• casting concrete into the prestressed composite girder;
• and
• introducing a compressive force to the prestressed composite girder by tensing the steel wires included in the sheaths after the concrete is cured.

A continuous prestressed composite girder structure, comprising:

• upper steel plates embedded in upper flanges of prestressed composite girders, provided with shear connecting members, and connected to each other in a butt welding manner;
• lower steel plates embedded in lower flanges of the prestressed composite girders, provided with shear connecting members, and connected to each other in a butt welding manner;
• an upper connecting plate placed on the upper steel plates and welded to the upper steel plates at four sides thereof in a fillet welding manner;
• a lower connecting plate placed under the lower steel plates and welded to the lower steel plates at four sides thereof in a fillet welding manner;
• and
• an epoxy resin adapted to fill a gap between the prestressed composite girders.

A continuous prestressed composite girder structure, the continuous prestressed composite girder structure being constructed by connecting preflex composite girders in a welding manner, comprising:

• upper and lower flanges of steel forms of the preflex composite girders connected in a butt welding manner;
• an upper connecting steel plate placed on the upper flanges of the steel forms and connected to the upper flanges of the steel forms at four sides thereof in a fillet welding manner;
• a lower connecting steel plate placed under the lower flanges of the steel forms and connected to the upper flange of the steel forms at four sides thereof in a fillet welding manner;
• and
• a web connecting steel plate placed besides webs of the steel forms of the preflex composite girders and connected to the webs of the steel forms at four sides thereof in a fillet welding manner.

A method of connecting prestressed composite girders, when constructing a continuous bridge, comprising:

• connecting upper and lower flange steel plates, which are embedded in upper flanges of prestressed composite girders in contact with each other, to each other in a butt welding manner;
• placing an upper connecting plate on the butt-welded upper flange steel plates and welding the upper connecting plate to the butt-welded upper flange steel plates at four sides thereof in a fillet welding manner;
• placing a lower connecting plate under the butt-welded lower flange steel plates and welding the lower connecting plate to the butt-welded lower flange steel plates at four sides thereof in a fillet welding manner;
• and
• injecting an epoxy resin into a gap between the prestressed composite girders in contact with each other and filling the gap with the epoxy resin.