Prestress introduction structure of truss girder and prestress introduction method

摘要

Provided is a prestress introduction structure of a truss girder provided with a prestress bonding portion introducing prestress into at least one of lower chords of a positive moment portion and upper chords of a negative moment portion in the continuous truss girder including the upper chords, the lower chords, and diagonal members formed as square steel pipes. The present invention includes a partition wall coupled to the inside of each of the square steel pipes on both sides of the prestress bonding portion; a cross-shaped point stiffener coupled to each outside of the partition wall and coupled to the inside of the square steel pipe; and a connecting bonding steel plate, a bolt, and a nut interconnecting and inter-coupling the upper and lower flanges and both web portions of the square steel pipes on both sides of the prestress bonding portion. A work hole is formed for internal and external communication between at least one of the upper flange and both web portions of the square steel pipes on both sides of the prestress bonding portion and the connecting bonding steel plate coupled thereto. A loading device is installed inside the prestress bonding portion, a load is applied in both directions, and the bolt and the nut are completely fastened. Then, the loading device is withdrawn from the prestress introduction structure of a truss girder. It is possible to significantly increase the tensile resistance of the upper and lower chords of a truss girder tensile region, and thus economical design is possible. The prestress introduction device and the introduction method based thereon are very simple, and thus work convenience is improved. Horizontal prestress introduction is possible, and thus tensile resistance can be increased more efficiently than in the case of vertical prestress introduction.