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THIS article considers the role of carbon fibre reinforced plastic as a reinforcement for conventional aircraft structural components. It is in this mode that we expect to see the most extensive use of this new material in the near future, particularly for applications in commercial airliners where, more than in most fields of engineering, it is necessary to temper the vital pressure for greater efficiency by an appreciation of the problems in attempting to achieve too much too soon. The conclusions are based on research and development by British Aircraft Corporation, Weybridge Division, during the past year, primarily in its intensive design development of the new wide‐bodied B.A.C. Three‐Eleven airliner.

In the preface it is stated that a need exists for a ‘comprehensive treatment of the subject that will present fundamentals in broad perspective but without emphasis on any one type of system’. The book is written as a single volume introduction to the subject so as to fill this need in part. The missiles dealt with in the book are what, in this country, would be more properly called guided missiles; the author states that the broader description ‘advanced’ was adopted to avoid implying any unintended restriction upon the applicability of basic principles. The book is competently written and a number of diverse technical aspects are handled in a workmanlike manner. There is a refreshing soundness and depth to the book which regrettably is not often found in books on guided missiles from across the Atlantic. To cover a subject embracing so many different techniques in a book of less than 600 pages is, of course, a difficult task. The treatment on the whole therefore has to be concise. This in itself is not a failing as the reader will generally be expert in at least one of the areas and will gain enough from the book to refresh his memory and enough to see what are the main features applicable to guided weapons. In areas where the reader is less well trained it will be necessary for him to supplement the text by reading elsewhere. To aid him in this the book is adequately provided with references (without overburdening the text). The treatment is a formal presentation of the basic theories, emphasising the common ideas underlying, for example, signal detection in the presence of noise and quality control. The reader would finish the book with a sound idea of the fundamentals but with only the vaguest idea of how to set about the design of a missile. What is required is a sequel to this book where the logical design, say, of three or four types of missiles is worked through with a generous number of examples.

A review of CFRP dealing with its processing, properties and some of the ways in which it could be used in conjunction with conventional materials. The importance of the utilization of carbon fibres in commercially useful as well as experimental structures is discussed. This may be achieved by using the fibres in conjunction with conventional sheet metal components, as a preliminary step toward the 100 per cent reinforced plastic structure. A few such applications are described, together with a brief summary of the fibre processing and properties as an aid to preliminary design studies.

A numerical simulation of the test beam was carried out with Abaqus and compared with test data to ensure that the modeling method is accurate. An analysis of the effects of the angle between the U-hoop and horizontal direction, the pre-crack height, the pre-crack spacing, and the strength of the geopolymer adhesive on the cracking load and ultimate load of the reinforced beam is presented.

Load tests and finite element simulations were conducted on carbon fiber reinforced polymer-reinforced concrete beams bonded with geopolymer adhesive. The bond-slip effect of geopolymer adhesive was taken into account in the model. The flexural performances, the flexural load capacities, the deformation capacities, and the damage characteristics of the beams were observed, and the numerical simulation results were in good agreement with the experimental results. An analysis of parametric sensitivity was performed using finite element simulation to investigate the effects of different angles between U-hoop and horizontal direction, pre-crack heights, pre-crack spacing, and strength of geopolymer adhesive on cracking load and ultimate load.

Under the same conditions, the higher the height of the pre-crack, the lower the bearing capacity; increasing the pre-crack spacing can delay cracking, but reduce ultimate load. By increasing the strength of the geopolymer adhesive, the flexural resistance of the beam is improved, and crack development is also delayed; the angle between the u-hoop and horizontal direction does not affect the cracking of reinforced beams; a horizontal u-hoop has a better effect than an oblique u-hoop, and 60° is the ideal angle between the u-hoop and horizontal direction for better reinforcement.

According to the experimental study in this paper, Abaqus was used to simulate the strength of different angles between U-hoop and horizontal direction, pre-crack heights, pre-crack spacings, and geopolymer adhesives, and the angles' effects on the cracking load and load carrying capacity of test beams were discussed. Since no actual tests are required, the method is economical. This paper offers data support for the promotion and application of environmentally friendly reinforcement technology, contributes to environmental protection, and develops a new method for reinforcing reinforced concrete beams and a new concept for finite element simulations.