Self-healing polymeric materials: A review of recent developments

The static strength of reinforced concrete beams strengthened by gluing glassfiberreinforcedplastic GFRP plates to their tension flanges is experimentally investigated. Five rectangular beams and o...

RC Beams Strengthened with GFRP Plates. I: Experimental Study

Bridge failures in recent earthquakes such as the 1989 Loma Prieta earthquake have attracted the attention of the bridge engineering community to the large number of bridges with substandard seismic design details. Many concrete columns in bridges designed before the new seismic design provisions were adopted have low flexural ductility, low shear strength, and inadequate lap length for starter bars. These problems, compounded by flaws in the design of structural systems, have contributed to the catastrophic bridge failures in recent earthquakes. In this paper, a new technique for seismic strengthening of concrete columns is presented. The technique requires wrapping thin, flexible high-strength fiber composite straps around the column to improve the confinement and, thereby, its ductility and strength. Analytical models are presented that quantify the gain in strength and ductility of concrete columns externally confined by means of high-strength fiber composite straps. A parametric study is conducted to examine the effects of various design parameters such as concrete compressive strength, thickness and spacing of straps, and type of strap. The results indicate that the strength and ductility of concrete columns can be significantly increased by wrapping high-strength fiber composite straps around the columns.

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Strength and ductility of concrete columns externally reinforced with fiber composite straps

In-service structural health monitoring of composite aircraft structures plays a key role in the assessment of their performance and integrity. In recent years, Fibre Optic Sensors (FOS) have proved to be a potentially excellent technique for real-time in-situ monitoring of these structures due to their numerous advantages, such as immunity to electromagnetic interference, small size, light weight, durability, and high bandwidth, which allows a great number of sensors to operate in the same system, and the possibility to be integrated within the material. However, more effort is still needed to bring the technology to a fully mature readiness level. In this paper, recent research and applications in structural health monitoring of composite aircraft structures using FOS have been critically reviewed, considering both the multi-point and distributed sensing techniques.

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Fibre Optic Sensors for Structural Health Monitoring of Aircraft Composite Structures: Recent Advances and Applications.

Bioinspired engineering of honeycomb structure – Using nature to inspire human innovation

Offering an introduction to the technology of composite materials as used in aeronautical design and structure, this text discusses differences between composites and metals, structural design procedures and in-service performance of those materials.

Composite Materials For Aircraft Structures

1. Introductory chapter.- 1.1 Bonded vs bolted repairs.- 1.2 Combined bonded/bolted repairs.- 1.3 Adhesives.- 1.4 Adhesive testing.- 1.5 Surface preparation.- 1.6 Environmental behaviour.- 1.7 Summary.- 2. Surface treatments for bonded repairs of metallic components.- 2.1 Introduction.- 2.2 Background.- 2.3 Structural aluminium alloys.- 2.4 Phosphoric acid anodizing.- 2.5 Chromic acid anodizing.- 2.6 Titanium alloys.- 2.7 Summary.- 3. Design and analysis of bonded repairs for metal aircraft structures.- 3.1 Introduction.- 3.2 Design of adhesive bonded repairs in thin sheet metal construction.- 3.3 Residual strength of flawed or damaged bonded joints.- 3.4 Acceptance criteria for bonded flaws and damage.- 3.5 The pitfalls of life prediction for adhesive-bonded joints.- 3.6 Surface preparation for adhesive bonded repair of metal structure.- 3.7 Conclusions.- 4. Crack patching: design aspects.- 4.1 Introduction.- 4.2 The finite element formulation.- 4.3 Repair of cracks in Mirage III lower wing skin - a design study.- 4.4 Neutral axis offset effects.- 4.5 Initial design procedures.- 4.6 Comparison with experimental and 3-D results.- 4.7 Repair of semi elliptical surface flaws.- 4.8 Repair of cracked holes.- 4.9 Repair of cracked fastener holes.- Appendix A.- 5. Theoretical analysis of crack patching.- 5.1 Introduction.- 5.2 Formulation and notation.- 5.3 Load transfer to bonded reinforcements.- 5.4 Two stage analytical solution.- 5.5 Residual thermal stress due to adhesive curing.- 5.6 Bending effects.- 5.7 Partial reinforcement.- 5.8 Conclusion.- 6. Crack patching: experimental studies, practical applications.- 6.1 Introduction.- 6.2 Adhesive system and process selection.- 6.3 Thermal and residual stress problems.- 6.4 Design correlations and materials allowables.- 6.5 A preliminary design approach.- 6.6 Crack propagation behaviour.- 6.7 Applications of crack patching.- 7. Repair of composite aircraft.- 7.1 Introduction.- 7.2 Composite fabrication.- 7.3 Defects.- 7.4 Repair materials.- 7.5 Bonded repair - composite repair concepts.- 7.6 Effect of moisture on bonded repairs of composites.- 7.7 Design of bonded repairs.- 7.8 Composite service damage experience.- 7.9 Specific component repair.- 7.10 Future requirements.

Alan Baker

Papers

Composite Materials For Aircraft Structures

Bonded repair of aircraft structures

Bonded composite repair of fatigue-cracked primary aircraft structure

Repair of cracked or defective metallic aircraft components with advanced fibre composites—an overview of Australian work

Damage tolerance of graphite/epoxy composites