Debonding in RC Beams Shear Strengthened with Complete FRP Wraps
- 1 October 2005
- journal article
- research article
- Published by American Society of Civil Engineers (ASCE) in Journal of Composites for Construction
- Vol. 9 (5), 417-428
- https://doi.org/10.1061/(asce)1090-0268(2005)9:5(417)
Abstract
Substantial research has been conducted on the shear strengthening of reinforced concrete (RC) beams with bonded fiber reinforced polymer (FRP) strips. The beams may be strengthened in various ways: complete FRP wraps covering the whole cross section (i.e., complete wrapping), FRP U jackets covering the two sides and the tension face (i.e., U jacketing), and FRP strips bonded to the sides only (i.e., side bonding). Shear failure of such strengthened beams is generally in one of two modes: FRP rupture and debonding. The former mode governs in almost all beams with complete FRP wraps and some beams with U jackets, while the latter mode governs in all beams with side strips and U jackets. In RC beams strengthened with complete wraps, referred to as FRP wrapped beams, the shear failure process usually starts with the debonding of FRP from the sides of the beam near the critical shear crack, but ultimate failure is by rupture of the FRP. Most previous research has been concerned with the ultimate failure of FRP wrapped beams when FRP ruptures. However, debonding of FRP from the sides is at least a serviceability limit state and may also be taken as the ultimate limit state. This paper presents an experimental study on this debonding failure state in which a total of 18 beams were tested. The paper focuses on the distribution of strains in the FRP strips intersected by the critical shear crack, and the shear capacity at debonding. A simple model is proposed to predict the contribution of FRP to the shear capacity of the beam at the complete debonding of the critical FRP strip.This publication has 26 references indexed in Scilit:
- SHEAR STRENGTHENING OF REINFORCED CONCRETE STRUCTURES USING FRP COMPOSITEPublished by Elsevier BV ,2004
- Reinforced Concrete T-Beams Strengthened in Shear with Fiber Reinforced Polymer SheetsJournal of Composites for Construction, 2003
- EFFECTIVE SHEAR STRENGTHENING OF CONCRETE BEAMS USING FRP SHEETS WITH BONDED ANCHORAGEPublished by World Scientific Pub Co Pte Ltd ,2003
- Shear Capacity of Fiber-Reinforced Polymer-Strengthened Reinforced Concrete Beams: Fiber Reinforced Polymer RuptureJournal of Structural Engineering, 2003
- Shear strengthening of reinforced concrete beams using different configurations of externally bonded carbon fibre reinforced platesMaterials and Structures, 2003
- Shear capacity of FRP-strengthened RC beams: FRP debondingConstruction and Building Materials, 2002
- Anchorage Strength Models for FRP and Steel Plates Bonded to ConcreteJournal of Structural Engineering, 2001
- FRP or steel plate-to-concrete bonded joints: Effect of test methods on experimental bond strengthSteel and Composite Structures, 2001
- Transfer Lengths and Bond Strengths for Composites Bonded to ConcreteJournal of Composites for Construction, 1999
- Shear Strengthening of RC Beams by Externally Bonded Side CFRP StripsJournal of Composites for Construction, 1998