Fiber Reinforced Plastics (FRP) are widely used for the design of load-bearing structures. Life time prediction based on failure analysis is therefore essential for many applications in Aeronautics, ...Automotive and Civil Engineering. Analysis of Failure in Fiber Polymer Laminates presents Alfred Puck´s failure model, which, among several other theories, predicts fracture limits best and describes the failure phenomena in FRP most realistically – as confirmed within the "World-wide Failure Exercise". Using Puck´s model the composite engineer can follow the gradual failure process in a laminate and deduce from the results of the analysis how to improve the laminate design. This capability distinguishes the model from other phenomenological and global models. It thus reduces the number of required component tests and iteration loops in the design process and paves the way to sorely needed software for crash-simulation of FRP-structures.
This book focuses on the numerical modelling of the pultrusion process. State-of-the-art process models are reviewed and the governing principles are explained in a systematic way. The main ...challenges in pultrusion such as the process induced residual stresses, shape distortions, thermal history, species conversion, phase changes, impregnation of the reinforcements and pulling force are described and related examples are provided. Moreover, the strategies for having a reliable and optimised process using probabilistic approaches and optimisation algorithms are summarised. Another focus of this book is on the thermo-chemical and mechanical analyses of the pultrusion process for industrial profiles such as rectangular box section, L-shaped profile, I-beam, flat and round profiles in which the process induced stresses and dimensional variations together with the thermal and cure developments are highlighted.
This book presents polymer-based fibre reinforced composite materials and addresses the characteristics of these widely used materials like low density and coefficient of thermal expansion, specific ...strength with better fatigue resistance and modulus. The topics discussed are laser-based material machining, high-speed robotic end milling and LFRP modeling, including definitions, features, machine elements (system set-up) as well as experimental and theoretical investigations. These investigations include effects of input variables (tool rotation speed, feed rate and ultrasonic power) on cutting force, torque, cutting temperature, edge quality, surface roughness, burning of machined surface, tool wear, material removal rate, power consumption and feasible regions.
The use of fiber-reinforced polymer (FRP) composite materials has had a dramatic impact on civil engineering techniques over the past three decades. FRPs are an ideal material for structural ...applications where high strength-to- weight and stiffness-to-weight ratios are required. Developments in fiber- reinforced polymer (FRP) composites for civil engineering outlines the latest developments in fiber-reinforced polymer (FRP) composites and their applications in civil engineering.Part one outlines the general developments of fiber-reinforced polymer (FRP) use, reviewing recent advancements in the design and processing techniques of composite materials. Part two outlines particular types of fiber-reinforced polymers and covers their use in a wide range of civil engineering and structural applications, including their use in disaster-resistant buildings, strengthening steel structures and bridge superstructures.With its distinguished editor and international team of contributors, Developments in fiber-reinforced polymer (FRP) composites for civil engineering is an essential text for researchers and engineers in the field of civil engineering and industries such as bridge and building construction. * Outlines the latest developments in fiber-reinforced polymer composites and their applications in civil engineering * Reviews recent advancements in the design and processing techniques of composite materials * Covers the use of particular types of fiber-reinforced polymers in a wide range of civil engineering and structural applications
Natural fibres have been used to reinforce materials for over 3,000 years. More recently they have been employed in combination with plastics. One of the earliest examples (1950) was the East German ...Trabant car, the body was constructed from polyester reinforced with cotton fibres. Currently many types of natural fibre are being investigated for use in plastics including: flax, hemp, jute, straw, wood fibre, rice husks, wheat, barley, oats, rye, cane (sugar and bamboo), grass, reeds, kenaf, ramie, oil palm empty fruit bunch sisal, coir, water hyacinth, pennywort, kapok, paper-mulberry, raphia, banana fibre, pineapple leaf fibre and papyrus. Natural fibres have the advantage that they are renewable resources and have marketing appeal. Many, such as pineapple leaf fibre are natural waste products and hence available at minimal cost. However, there can be problems with the technical properties of reinforced materials - moisture absorption is generally high and impact strength is relatively low. The Asian markets have been using natural fibres for many years. For example, jute is a common reinforcement in India. Natural fibres are increasingly being used in the automotive industry in Europe. In 1999 consumption was 21,300 tons and by 2000 this had risen to 28,300 tons. Packaging is a further application in Europe, particularly in Germany. In North America wood/polymer composites amount to a 300,000 ton/year market for use in building and garden products, particularly decking. Wood fibres can be subdivided into two types - hardwood and softwood. These have difference properties. Steam explosion is a common pretreatment for wood fibres as it can increase the specific surface and improve properties of composites, however it can also have a negative effect. A compatibiliser such as maleic anhydride can be more beneficial. This report examines the
different fibre types available and the current research. The authors have cited several hundred references to the latest work on properties, processing and applications. The different methods of fibre pretreatment are examined, together with fibre properties, chemistry and applications. This review is accompanied by summaries of papers from the Polymer Library. These papers are referenced in the report and are also indexed to allow the reader to search for information on specific topics. Key features…; Natural fibre types; Chemistry; Properties; Processing; Applications. Save 20% when you buy 2 or more titles in the Rapra Review Report Series (Volume 9 onwards). Just enter promotional code RRR20 when you get to the shopping cart. Please click here to see the full list of reports available.
Fibre reinforced polymer (FRP) composites are used in almost every type of advanced engineering structure, with their usage ranging from aircraft, helicopters and spacecraft through to boats, ships ...and offshore platforms and to automobiles, sports goods, chemical processing equipment and civil infrastructure such as bridges and buildlings. The usage of FRP composites continues to grow at an impessive rate as these materials are used more in their existing markets and become established in relatively new markets such as biomedical devices and civil structures. A key factor driving the increased applications of composites over the recent years is the development of new advanced forms of FRP materials. This includes developments in high performance resin systems and new styles of reinforcement, such as carbon nanotubes and nanoparticles. This book provides an up-to-date account of the fabrication, mechanical properties, delamination resistance, impact tolerance and applications of 3D FRP composites. The book focuses on 3D composites made using the textile technologies of weaving, braiding, knitting and stiching as well as by z-pinning.
Depuis quelques années les matériaux composites à base de fibres naturelles sont de plus en plus utilisés pour les nouvelles performances qu’ils proposent. C’est surtout au niveau des fibres ...naturelles que de nouvelles propriétés sont proposées. Dans ce travail, nous nous sommes essentiellement intéressés aux fibres naturelles de chanvre. Ces fibres sont déjà fortement utilisées dans l’automobile et la construction. En Europe, ces fibres sont produites principalement en France et plus particulièrement dans l’Aube. Pour développer des agro-composites hautes performances, c’est sous la forme de fibres longues et de tissus que nous avons choisi d’orienter ce travail de thèse. Nous avons choisi la thermocompression pour élaborer des plaques avec des tissus de chanvre et une matrice en polypropylène (PP). Ce travail permet de voir l’influence des conditions d’élaboration sur le comportement mécaniques de ces agro-composites. Cette thèse permet aussi de voir l’effet du vieillissement aux UV et à l’Humidité sur les performances de ces matériaux. Enfin une analyse des contraintes résiduelles par la méthode du trou incrémental permet de voir leurs effets sur ces agro-matériaux
In recent years composite materials based on natural fibers are more and more used for their new performances. Natural fibers propose attractive environmental, mechanical and thermal properties.In this work, we are firstly interested in hemp fibers. These fibers are already used in the automotive and construction industry. In Europe, these fibers are produced mainly in France and especially in Aube. To develop agro-composites with high performances, we have focused this thesis on hemp woven. We chose to elaborate the plates with hemp woven and a polypropylene matrix (PP) by compression molding. This work allows us to see the influence of elaboration conditions on the mechanical behavior of these agro-composites. This thesis also allows us to see the effect of aging conditions UV and humidity on the performance of these materials. Finally an analysis of residual stresses determined by the hole drilling method is proposed to see their effects on the agro-materials
L’utilisation des fibres végétales dans les polymères composites suscite de nombreuses investigations. Avant de mélanger les fibres végétales dans le polymère, un traitement chimique peut être ...effectué permettant de réduire l’hydrophilicité des fibres et d’améliorer l'adhérence à l’interface fibre/matrice. Dans cette thèse, l'eau et l'alcali sont utilisés d'abord pour traiter les fibres de chanvre, puis trois agents silane : 3-(triméthoxysilyl)propyl méthacrylate (MPS), N-3- (triméthoxysilyl)propyl aniline (PAPS) et (3-Aminopropyl)-triéthoxysilane (APS), sont utilisés pour modifier plus ou moins la surface des fibres de chanvre. Ces fibres traitées ou modifiées sont ensuite mélangées avec le polypropylène (PP) pour la fabrication des composites. Les effets de ces différents traitements sur la structure, les composants et l’hydrophilicité des fibres, et les propriétés mécaniques de ces composites sont mis en évidence. Nous avons étudié ensuite l’effet de vieillissement sur leurs comportements mécaniques, notamment l'humidité, la température et le rayonnement ultraviolet. Les résultats ont montré que le traitement de fibres par l'eau et l’alcali a des effets considérables sur la structure de fibres, les propriétés mécaniques et la durabilité des composites renforcés. La modification par l'agent de silane a une influence moins importante sur la structure des fibres, pourtant son groupe fonctionnel a une influence significative sur les propriétés mécaniques et la résistance au vieillissement des composites renforcés
Using agro fiber as reinforcement of polymer com-posites attracts numerous investigations due to the good mechanical properties and environmental benefits. Prior to blend agro fiber with polymer, chemical treatment can be employed to treat agro fiber for the purpose of reducing the hydrophilicity of fiber and improving the interfacial adhesion fi-ber/polymer matrix. In this thesis, water and alkali are utilized to treat hemp fiber firstly and then three silane agent as 3-(Trimethoxysilyl)propyl methacry-late (MPS), N-3-(Trimethoxysilyl)propylaniline (PAPS) and (3-Aminopropyl)-triethoxysilane (APS) are employed to modify the hemp fiber surface. These treated or modified fibers are blended respectively with polypropylene (PP) to fabricate the hemp fiber/PP composites. The effects of these different treatments on the structure, components and hydro-philicity of fiber, and the mechanical properties of the reinforced PP composites are studied. Moreover, the accelerated ageing experiments including humidity, temperature and ultraviolet of the reinforced PP composites are conducted. The results showed that the fiber treatment of water and alkali has a considerable effect on fiber structure, mechanical properties and durability of the reinforced compo-sites. The silane agent modification of fiber has less influence on the fiber structure but its functional group has great influence on the mechanical proper-ties and ageing resistance of the reinforced compo-sites.
