《建筑科学与工程学报》[ISSN:1673-2049/CN:61-1442/TU]
- Issue:
- 2018年06期
- Page:
- 66-72
- Research Field:
- Publishing date:
Info
- Title:
- -
- Author(s):
- Experiment of Prestressed CFRP Reinforced High Strength Concrete Beams
- State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology
- Keywords:
- CFRP; prestress; high strength concrete; ultimate load; ductility
- PACS:
- -
- DOI:
- -
- Abstract:
- The comparative studies of prestressed carbon fiber reinforced plastics (CFRP) reinforced concrete beams and non-reinforced concrete beams including mechanical process, failure pattern, ductility and beam bottom CFRP strain were carried out through the four-point bending test. The flexural performance of reinforced beam under three kinds of prestress levels of 0, 0.15fcfk, 0.30fcfk?(fcfk?was CFRP tensile strength standard value) was studied. The results show that the failure modes of the test beams are all close to the interface failure caused by the middle bending shear crack. When the prestress level of CFRP is increased from 0 to 0.15fcfk, 0.30fcfk, the uplift of reinforced concrete beam is basically same to reinforced concrete beam, the ultimate load of unreinforced concrete beam is increased by 8% and 28% respectively, and the ultimate load of reinforced concrete beam is increased by 10% and 25% respectively. With the increase of CFRP prestress level, the stripping failure of strengthening beam bottom is changed from failure of resin lay into interface failure of glue layer and concrete. Compared to the plain concrete beam, the number of cracks of prestressed CFRP reinforced concrete beams increases obviously, crack propagation speed is slow, the cracks are uniform distributed in reinforcement beam on both sides, however the cracks of plain concrete beam are mainly distributed in a side, and ductility of reinforced concrete beam reinforcement has increased significantly. Compared with the CFRP prestress level increasing from 0 to 0.15fcfk, when the CFRP prestress level increasing from 0.15fcfk?to 0.30fcfk, the midspan strain of CFRP beam bottom of is greatly improved, and the utilization rate of CFRP strengthened by prestressed CFRP is improved too.
Last Update: 2018-11-22