This book presents a unified approach to fracture behavior of natural and synthetic fiber-reinforced polymer composites on the basis of fiber orientation, the addition of fillers, characterization, properties and applications. In addition, the book contains an extensive survey of recent improvements in the research and development of fracture analysis of FRP composites that are used to make higher fracture toughness composites in various applications.The FRP composites are an emerging area in polymer science with many structural applications. The rise in materials failure by fracture has forced scientists and researchers to develop new higher strength materials for obtaining higher fracture toughness. Therefore, further knowledge and insight into the different modes of fracture behavior of FRP composites are critical to expanding the range of their application.

Application of Fracture Mechanics to Polymers, Adhesives and Composites

It is commonly accepted that the majority of engineering failures happen due to fatigue or fracture phenomena. Adhesive bonding is a prevailing joining technique, widely used for critical connections in composite structures. However, the lack of knowledge regarding fatigue and fracture behaviour, and the shortage of tools for credible fatigue design, hinders the potential benefits of adhesively bonded joints. The demand for reliable and safe structures necessitates deep knowledge in this area in order to avoid catastrophic structural failures. This book reviews recent research in the field of fatigue and fracture of adhesively-bonded composite joints. The first part of the book discusses the experimental investigation of the reliability of adhesively-bonded composite joints, current research on understanding damage mechanisms, fatigue and fracture, durability and ageing as well as implications for design. The second part of the book covers the modelling of bond performance and failure mechanisms in different loading conditions. - A detailed reference work for researchers in aerospace and engineering - Expert coverage of different adhesively bonded composite joint structures - An overview of joint failure

A plate composed of two dissimilar materials, bonded together along a straight line with a center crack was studied. This problem represents an idealization of an adhesive joint or a composite structure with an interfacial flaw or crack caused by faulty joining techniques. Common examples are imperfections, voids, or broken bonds on the composite interface. Combined with the finite element technique, the strain energy method and the J-integral method have been extended to a bi-material problem to calculate the value of the strain energy rate. A general relationship between strain energy rate and total stress intensity factor is then derived using the crack closure technique. The ratio of stress intensity factors was also examined. The numerical analysis concentrated on three categories of composite materials with moduli ratio 1, 20, and 120. These results provide a complete crack-tip stress analysis and are needed for the study and understanding of the fracture mechanics of bi-material problems. Lastly, the compliance method was employed for experimental verification of the numerical results. An aluminum alloy-epoxy bi-material plate with a moduli ratio equal to 20 was examined. This study has yielded useful results in terms of the analytical tools to guide further experimental fracture studies of adhesive joints and composite materials. (Author, modified-PL).