A manufacturing method of a composite steel box girder using prestressed concrete for a positive moment area of a bridge

摘要

PURPOSE: A method for manufacturing a steel box girder using pre-stressed concrete is provided to reduce the depth of a composite girder, and to reduce the sagging caused by live load by increasing the flexible rigidity of the steel box girder. CONSTITUTION: A method for manufacturing a steel box girder using pre-stressed concrete comprises following steps. A shear connector(8) connected to the upper surface of a lower flange(4) installs pre-cast lower concrete on a lower flange to be positioned at a through hole formed in precast lower concrete(9). A tendon(19) is installed in a duct formed in the longitudinal direction of the girder of the pre-cast lower concrete. An anchorage device installed on both ends stretches the tendon, and applies pre-stress. The lower flange of a steel composite girder(5) is integrated with pre-stressed lower concrete(11) by injecting non-shrinkage mortar into the through hole.