Title:
Improved Anchoring System for CFRP Strips
Author(s):
Nabil F. Grace
Publication:
Concrete International
Volume:
23
Issue:
10
Appears on pages(s):
54-60
Keywords:
DOI:
Date:
10/1/2001
Abstract:
Many existing reinforced-concrete structures have become weak because of deteriorating steel reinforcement, exposure to adverse environmental conditions, seismic loading, and increases in their service loads or the amount of traffic they carry. Carbon-fiber-reinforced polymer (CFRP) strips can improve the stiffness, strength, and durability of these structures. These strips have high specific strength and stiffness, high durability, low creep, and high fatigue resistance in comparison with conventional materials. However, their performance depends on the strength of the adhesive used to bond the strips to the concrete surface and the degree of stress at the interface of the concrete and the strips, which governs the onset of delamination. Critical modes of failure, such as debonding of the strips from the concrete (due to failure at the concrete-adhesive interface) and shear-tension failure (delamination of concrete cover), can limit improvements in structures strengthened with CFRP. Also, these structures may require a higher factor of safety in their design.