In recent years, the use of Fiber Reinforced Polymers (FRP) as externally bonded reinforcement has gained widespread acceptance as an innovative technique for the maintenance, rehabilitation and upgrading of existing or newly build reinforced concrete structures. The aim of this thesis is to gain a proper understanding of the structural behavior of reinforced concrete beam strengthened with multi-layered CFRP laminates.
It is well-known that the topic of composite mate- rials affects many engineering fields, such as civil, mechanical, aerospace, automotive and chemical. In the last decades, in fact, a huge number of scientific papers concerning these peculiar constituents has been published. Analogously, the industrial progress has been extremely noticeable. The study of composite materials, in general, is a challenging activity since the advancements both in the academia and in the industry provide continually new sparks to develop innovative ideas and applications. The communication, the sharing and the exchange of views can surely help the works of many researchers. This aspect represents the main purpose of this Conference, which aims to collect high-level contributions on the development and the application of composite materials. The establishment of this 21st edition of International Conference on Composite Structures has appeared appropriate to continue what has been begun during the previous editions. ICCS wants to be an occasion for many researchers from each part of the globe to meet and discuss about the recent advancements regarding the use of composite structures, sandwich panels, nanotechnology, bio-composites, delamination and fracture, experimental methods, manufacturing and other countless topics that have filled many sessions during this conference. As a proof of this event, which has taken place in Bologna (Italy), selected plenary and key-note lectures have been collected in the present book.
Structural elements such as beams, slabs and columns may require strengthening during their service life period. The need for strengthening may arise due to one or a combination of several factors including construction or design defects, increased load carrying demands, change in use of structure, seismic upgrade, or meeting new code requirements. Studies have shown that Fiber Reinforced Polymer (FRP) composites, in the form of sheets, have emerged as a viable, cost-effective alternative to steel plates or other techniques in strengthening RC members. The principal advantages of FRP sheets over steel plates include high strength-to-weight ratio, corrosion resistance and flexibility in its use. Another significant advantage of this repair technique is that overall repair cost in terms of labor, material and equipment is low and can offset the high material cost. However, the long-term durability and performance of FRP sheet strengthened RC members is a concern in civil engineering community. This work study involves experimental and theoretical investigations of the behavior of flexural debonding carbon fiber reinforced polymer (CFRP) laminates with steel anchorages.
The contents of this book have been chosen with the following main aims: to review the present coverage of the major design codes and the CIRIA guide, and to explain the fundamental behaviour of deep beams; to provide information on design topics which are inadequately covered by the current codes and design manuals; and to give authoritative revie
In December 1996, CEB established a Task Group with the main objective to elaborate design guidelines for the use of FRP reinforcement in accordance with the design format of the CEB-FIP Model Code and Eurocode2. With the merger of CEB and FIP into fib in June 1998, this Task Group became fib TG 9.3 FRP Reinforcement for concrete structures in Commission 9 Reinforcing and Prestressing Materials and Systems. Finally, as a result of the restructuring of fib’s Commissions and Task Groups at the end of 2014, the Task Group became fib T5.1 FRP Reinforcement for concrete structures, chaired by Stijn Matthys at Ghent University, in Commission 5 Reinforcements. The work of former TG 9.3 and current T5.1 was performed by two working parties (WP), one of which is “Externally Applied Reinforcement” (EAR), which produced fib bulletin 14 “Externally bonded FRP reinforcement for RC structures” in July 2001. Following a number of years of relatively slow activity, the WP on externally applied reinforcement was reactivated and started working on an update of bulletin 14. The result of this work is summarised in the present technical report, which aims to give design guidelines on the use of externally applied FRP reinforcement (both externally bonded and near-surface mounted) for concrete structures. An attempt has been made to present some of the topics in a Eurocode-compatible format, so that the material covered may form the basis for the introduction of composites in the next version of Eurocode 2 and for the updating of the text on seismic retrofitting with composites in the next version of Eurocode 8. All persons who participated in the preparation of this Bulletin are mentioned in the copyright page. Further acknowledgements are due to Josée Bastien (Canada), Hans Rudolf Ganz (Switzerland) and Luc Taerwe (Belgium) for revision of the document. To all members of the working party on externally applied reinforcement our sincere thanks are expressed for the high quality and extensive work brought in on a voluntary basis.
"Carbon fiber reinforcement polymer (CFRP) composite sheets and plates are widely used nowadays in civil engineering applications to externally strengthen structural concrete elements against deficiencies in flexure and shear. These deficiencies could be due to an increase in loading, earthquake damage, or even design and/or construction defects. The current state of the art technique used in flexural strengthening of reinforced concrete (RC) beams is the externally bonding of CFRP sheets or plates to the beam’s tensile bottom surface (soffit). However, the beam’s soffit may be obstructed and not always readily accessible for strengthening. Only the beam’s sides that may be exposed become the only accessible area for strengthening using side-bonded CFRP sheets or plates. As a result, this study aims to evaluate the performance of RC beams externally strengthened in flexure with side-bonded CFRP composite sheets. Accordingly, a total of 25 beams has been cast and strengthened in flexure with different configurations of side-bonded CFRP sheets. The strengthening scheme, amount of steel and CFRP reinforcement were varied to examine their effect on the flexural strength and ductility of RC beams. The flexural strength and load-deflection response curves of the tested specimens were also predicted using the ACI 440.2R-08 design guidelines. The predicted results were in good agreement with the experimental results. It was concluded that the side-bonded strengthening scheme is less efficient than that of the conventional soffit-bonded one; however, it is a viable solution when the beam’s soffit is not accessible for strengthening. The debonding mechanism of the side-bonded specimens justifies the efficiency reduction in this technique, since the stress distribution is not uniform along the CFRP sheets as in the soffit-bonded ones. However, as the reinforcement ratio increases, the performance of both strengthening schemes exhibit similar performance."--Abstract.
Fibre-reinforced polymer (FRP) composites are used to strengthen reinforced concrete (RC) structures. A large amount of research now exists on this. This book brings together all existing research into one volume.
This book presents the selected peer-reviewed proceedings of the International Conference on Recent Trends and Innovations in Civil Engineering (ICRTICE 2019). The volume focuses on latest research and advances in the field of civil engineering and materials science such as design and development of new environmental materials, performance testing and verification of smart materials, performance analysis and simulation of steel structures, design and performance optimization of concrete structures, and building materials analysis. The book also covers studies in geotechnical engineering, hydraulic engineering, road and bridge engineering, building services design, engineering management, water resource engineering and renewable energy. The contents of this book will be useful for students, researchers and professionals working in civil engineering.
