Normalized Test for Prediction of Debonding Failure in Concrete Elements Strengthened with CFRP

This work presents results of an experimental research program, conducted at the Technical University of Catalonia, to study the debonding behavior of carbon fiber-reinforced polymers (CFRPs) used to strengthen beams in bending. The research is a part of a program that aims to study the strengthening of concrete bridges (both monolithic and segmental) using CFRPs. The overall objective of this paper is to present results obtained from bond tests performed on material-scale specimens and full-scale tests performed on monolithic and segmental beams. A normalized test is proposed to obtain a more reliable estimate of the debonding strain of CFRPs, which may govern the design of CFRP-strengthened concrete structures. The test is proposed to supplement available design models, as the formula of k(sub)m included in ACI 440.2R-02 by ACI Committee 440. Results from the tests are checked with data obtained in large scale tests, representative of actual bridges. The reported values are significantly lower than those reported in other tests with specimens of a lower size. An explanation is that a size effect can exist, which affects the debonding failure mechanisms. Extrapolation of results, from models calibrated with specimens of reduced dimensions to real structures, may lead to unsafe predictions of debonding strain. In conclusion, the proposed simplified bond test more accurately estimates load bearing capacity, which in practical cases is not perfectly well covered by existing models (when discontinuities [cracks or joints] exist in the concrete where the CFRP is bonded).

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/10900268
• Authors:
  • Ramos, Gonzalo
  • Casas, J R
  • Alarcon, A
• Publication Date: 2006-11

Language

• English

Media Info

• Media Type: Print
• Features: Figures; Photos; References; Tables;
• Pagination: pp 509-519
• Serial:
  • Journal of Composites for Construction
  • Volume: 10
  • Issue Number: 6
  • Publisher: American Society of Civil Engineers
  • ISSN: 1090-0268
  • EISSN: 1943-5614
  • Serial URL: http://ascelibrary.org/journal/jccof2

Subject/Index Terms

• TRT Terms: Bonding and joining; Bridge engineering; Carbon fibers; Composite construction; Composite materials; Concrete structures; Debonding; Fiber reinforced plastics; Material reinforcement; Rehabilitation; Retrofitting; Structural connection; Structural members; Structural strengthening
• Subject Areas: Bridges and other structures; Design; Highways; I24: Design of Bridges and Retaining Walls;

Filing Info

• Accession Number: 01042281
• Record Type: Publication
• Files: TRIS
• Created Date: Mar 1 2007 8:37AM