2. Poly(lactic acid) bio-composites based on natural fibres
2.1. Structure and properties of natural fibres
2.2. Structure and properties of PLA
2.3. Natural fibres used in PLA based bio-composites
3. Strategies for improving interfacial adhesion in PLA/natural fibre composites
3.1. Chemical techniques
3.1.1. Alkaline treatment
3.1.2. Silane treatment
3.1.3. Esterification of natural fibres
3.1.4. Isocyanate treatment
3.2. Physical techniques
3.3. Toughening mechanisms in PLA/wood-flour composites
4. Conclusions
Author details
References
Section 2 Applications in Concrete Repair with FRP
Chapter 3 The Use of Fiber Reinforced Plastic for The Repair and Strengthening of Existing Reinforced Concrete Structural Elements Damaged by Earthquakes
1. Introduction
1.1. Damage observations for contemporary R/C structures
1.2. Structural damage description at the level of the structural element
1.3. The strategy for the repair and strengthening scheme
2. Main applications for dealing with earthquake structural damage utilizing fiber reinforcing plastics
2.1. Upgrading the flexural capacity of slabs
2.2. Upgrading the flexural and shear capacity of beams
2.2.1. The initial reinforced concrete beam specimen and its observed behavior.
2.2.2. Repaired beam specimen BEAM 1R-1 and observed behavior.
2.3. Repaired specimen Beam 1R-2
2.3.1. Observed Behavior of Specimen BEAM 1R-2
2.3.2. Evaluation of the contribution of the CFRP-hoops for BEAM 1R-2
2.3.3. Shear capacity of specimen BEAM 2R-1 based on the observed failure mechanism
2.4. Concluding observations
3. Partial Confinement
3.1. The use of confinement for upgrading the flexural and shear capacity of columns.
3.1.1. The formation of test specimens
3.1.2. Construction of test specimens
3.1.3. Critical parameters and their variation:
3.1.4. Instrumentation to obtain the average stress-strain behavior
3.2. Discussion of the results
3.2.1. Partial confinement of low effectiveness
3.2.2. Partial confinement of considerable effectiveness
3.2.3. Very effective partial confinement
3.3. Concluding remarks
4. Upgrading the flexural capacity of (R/C) vertical members
4.1. Flexural upgrading
4.1.1. The virgin beam specimen
4.1.2. The Loading sequence
4.2. Observed Behavior - Results
4.2.1. The behavior of Pier A
4.2.2. Repaired specimen Rep-1 Pier A and observed behavior
4.2.3. Observed Behavior of Specimen Rep-1 Pier A
4.2.4. Repaired specimen Rep-2 Pier A and observed behavior
4.2.5. Observed Behavior of Specimen Rep-2 Pier A
4.2.6. Repaired specimen Rep-3 Pier A and observed behavior
4.2.7. Observed Behavior of Specimen Rep-3 Pier A
4.3. Concluding Observations
5. Relevant code provisions - Emphasis in the application of FRP strips for shear strengthening
6. Special study for anchoring FRP strips
6.1. Concluding Observations
7. Basic qualification tests for fiber reinforcing polymers (FRP) sheets to be used in dealing with earthquake structural damage.
7.1. Bond Strength between CFRP layers and Concrete Substrate.
7.2. Cost estimates
8. Conclusions
Author details
References
Chapter 4 Applying Post-Tensioning Technique to Improve the Performance of FRP Post-Strengthening
1. Introduction
2. Reinforced concrete elements post-strengthened with prestressed FRP strips
2.1. Losses of prestressing force
2.2. Maximum prestressing force
2.3. Prestressing techniques
2.3.1. Cambered beam prestressing technique
2.3.2. FRP prestressed against the strengthened element
2.3.3. Technique of prestressing FRP prior to bonding
2.3.4. Prestressing method developed by Stoecklin
2.4. Failure Modes of reinforced concrete beams post-strengthened with prestressed FRP submitted to static loading
2.5. Failure of post-strengthened beams submitted to cyclic loading
3. Experimental analysis of reinforced concrete beams post-strengthened with prestressed FRP
3.1. Description of specimens
3.2. Reinforced concrete beams
3.3. Post-strengthening system
3.4. Post-strengthening procedure
3.5. Test Procedure
3.6. Behavior of post-strengthened beams tested under static loading
3.6.1. Loads and failure modes
3.6.2. Displacements at mid-span
3.6.3. Anchorage system
3.7. Behavior of post-strengthened beams tested under cyclic loading
3.7.1. Beam VFC_PC_01
3.7.2. Beam VFC_PC_02
4. Conclusions
4.1. Post-strengthened beams tested under static loading
4.2. Post-strengthened beams tested under cyclic loading
Author details
References
Chapter 5 Hybrid FRP Sheet – PP Fiber Rope Strengthening of Concrete Members