Generally, a precast prestressed concrete (PSC) beam is used as girders for short-to-medium span (less than 30 m) bridges due to the advantages of simple design and construction, reduction of construction budget, maintenance convenience. Recently, bridge construction industries have strived to develop a most cost-competitive bridge with longer span. To develop a new type of long span bridge, PSC hollow box girder with H-type steel beam placed at the compressive region is proposed to develop a PSC bridge with a span of more than 50 m. The unbonded compressive prestressing in the H-type steel beams in the girder is made to recover plastic deflection of PSC girder since releasing the pre-stressing. A quasi-static 3-point bending test with 4 different loading steps is performed to verify safety and plastic deflection recovery of the girder. The experimental results showed that the maximum applied load exceeded the maximum design load and most of the plastic deflection was recovered when the compressive prestressing of H-type steel beams is released. Also using prestressed H-type steel as compression reinforcements in the upper part of cross section, repair and restoration difficulty and cost of PSC girders should be significantly reduced. The study result and analysis are discussed in detail in the paper.
All Science Journal Classification (ASJC) codes
- Computational Mechanics