Aramids concrete reinforcement

Odagiri, T., K. Matsumoto and H. Nakai (1997). Fatigue and relaxation characteristics of continuous aramid fiber reinforced plastic rods. Non-Metallic (FRP) Reinforcement for Concrete Structures, FRPRCS-3, Sapporo, Japan, pp. 227-234. 

Creep behavior of aramid fiber reinforced plastic rods in air and alkaline solution, with and without embedding in concrete [lOIIJ... 

A. Nanni, Properties of aramid fibre reinforced concrete and SIFCON, ASCE J. Materials in Civil Engineering. 2,1992,1-15. 

If concrete removal is not required or supplementary reinforcing bars cannot be used, external reinforcement can be applied. For instance, steel bars may be encased in a shotcrete layer or steel plates may be bonded onto the concrete surface. Recently, the use of steel plates has been substituted by fibre-reinforced plastics (F. R.P.), that are composite materials with glass, aramide or carbon fibres embedded in a polymeric matrix (usually an epoxy system). F. R.P. are available in the form of laminates or sheets that are bonded to the concrete surface using an epoxy adhesive [11]. They are typically used to improve the flexural and shear strength or to provide confinement to concrete subjected to compression. The... 

When the coloring of latex-modified mortar and concrete is required, alkali-resistant, weatherproof pigments are used. Furthermore, it is important that the pigments do not obstruct the stability of polymer latexes and the hydration of cements. Alkali-resistant glass, steel, polyamide, polypropylene, polyvinyl alcohol (poval), aramid and carbon fibers are employed as mixable reinforcements. Reinforcing bars for ordinary cement concrete are also used for the reinforcement of the latex-modified concrete. 

Techniques for production of 3-D structures of high tenacity aramid fiber have also been developed, offering excellent fatigue resistance to abrasion, flexure, and stretching. One such system is on a wire frame basis, with mechanized frame building, and it is proposed as reinforcement for concrete pillars and other structures. As well as the strength of the fiber, this application exploits the high chemical resistance of aramid to acids, alkalis, and cement. 

Carbon/Aramid Fiber Sheet Jacketing Method. The application of carbon/aramid fiber sheet for the reinforcement of concrete pier is adopted when restricted conditions are present on site, such as no permit of sectional increase due to clearance limit or weight increase on the foundation. The sheet in longitudinal direction is effective to increase the flexural strength and the sheet in transverse direction acts as lateral reinforcement to raise the shear strength. Particularly the fiber sheet is concentrically bonded at the termination of longitudinal rebar at the mid-height. 

Sumida, A., Reinforcement, retrofit of concrete structures with aramid fiber, in FRP Composites in Civil Engineering, Proceedings of the International Conference on FRP Composites in Civil Engineering, Hong Kong, China, December 12-15, 2001, Teng, J.G., Ed., Elsevier, Amsterdam, 2001, p. 273. 

The Japanese are also active in the application of fibre reinforced plastics to reinforced concrete structures to improve their earthquake resistance. Kabatake et al [22] reported on 14 cases in which chimneys were retrofitted with fibre reinforced plastics and were judged by the Building Disaster Prevention Association of Japan to be one of the most effective retrofitting methods. In this retrofitting programme, carbon fibre tapes impregnated with an epoxy resin were wound and adhered to the exterior of the chimney. Sumida et al [ 23] have described experiences with aramid reinforced... 

Fibre reinforced polymers (FRPs) are composed of a reinforcement material (glass, aramid or carbon fibres) surrounded and retained by a (thermoplastic or thermosetting) polymer matrix (unsaturated polyester, epoxy, vinyl ester, or polyurethane). FRPs were first used in the rehahiUtation of reinforced or pre-stressed concrete, but they have also been widely used in the reinforcement of timber structures. 

The use of fiber-reinforced polymer (FRP) composite materials in the reinforcement of concrete structures has shown important results. These interventions are based on the application of carbon fiber, glass, or aramid impregnated with thermosetting polymers. The effectiveness of these interventions is demonstrated both by extensive research in the laboratory and by applications to existing structures. 

Masukawa, J., Akiyama, H., and Saito, H. (1997). Retrofit of existing reinforced concrete piers by using carbon fiber sheet and aramid fiber sheet . In Proceedings of the Third International Symposium on Non-Metallic (FRP) Reinforcement for Concrete Structures, Vol. 1. 

H.J. Schurhoff and A. Gerritse, Aramid reinforced concrete (ARC), aramid fibres of the twaron type, for prestressing concrete , in R.N. Swamy, R.L. Wagstaffe and D.R. Oakley (eds) Developments in Fibre Reinforced Cement and Concrete, Proc. RILEM Symp., Sheffield, RILEM Technical Committee 49-FTR, 1986, Paper 2.6. J.L. Daniel and E.D. Anderson, Acrylic fibre reinforced cement composites , in R.N. Swamy, R.L. Wagstaffe and D.R. Oakley (eds) Developments in Fibre Reinforced Cement and Concrete, Proc. RILEM Symp., Sheffield, RILEM Technical Committee 49-FTR, 1986, Paper 2.8. 

C. Meyer and G. Vilkner, Glass concrete thin sheets prestressed with aramid fiber mesh , in A.E. Naaman and H.W. Reinhardt (eds) Fourth International Warkshop on High Performance Fiber Reinforced Cement Composites (HPFRCC 4), RILEM Publications, Bagneux, France, 2003, pp. 325-336. 

Since important properties of the poly(p-aramide)s are quite different from those of Nomex , most apphcations are also different. Characteristic are applications as bullet-proof body armor, cut-fast gloves, substitute of asbestos, and as reinforcing component in concrete. They are also used as fibers in high performance tires for airplanes and racing cars, or as laminates for the constmction of boat hulls. Furthermore, poly(p-aramide)s are used for the production of sports articles, drum heads, brake pads, turbo hoses, optical fiber cables, or electrical-mechanical cables. Their fabrics serve as hot air filters and in combination with Nomex for the production of protective clothing and helmets. The total production of polyaramides amounts in 2008 to 60,000 tons. 

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