International Concrete Abstracts Portal

Recently, a non-metallic reinforcement is developed using new synthetic fiber, such as carbon, aramid and vinylon fiber in Japan. The fiber is made into a FRP rod. This material has advanced properties, for example, corrosion free, light weight and high strength, and are expected to apply for the practical structures. However, it is important to study engineering properties and design method in many fields theoretically and experimentally. In present paper, the bond characteristics are discussed because the expansion coefficient of non metallic fiber is different from conventional concrete. The results from the pull-out tests are, (l)the bond strength of FRP rod is ensured for the concrete structures, and (2)the deterioration of bond property is not appeared in CFRP, GFRP and VFRP however a little reduction is observed at AFRP rod.

"The American Concrete Institute sponsored an unprecedented six technical sessions on FRP Reinforcement for Concrete at the Vancouver Conference on March 28-31, 1993. Speakers and attendees were present from Europe, Japan, Canada and the United States. The papers in this Special Publication are organized in the same subject areas as the conference. The subject topic areas and symposium sections are: 1. FRP Material Properties and Testing Methods 2. FRP Reinforcement for Reinforced Concrete 3. FRP Reinforcement for Prestressed Concrete 4. Analysis And Design 5. The Japanese National Project for FRP Development 6. Applications of FRP Reinforcement The 55 technical papers in this report represent the most comprehensive compilation to date of FRP research, design, and application information. A comparison of the papers provides an insight to the approach to the use and development of FRP reinforcement within the research communities of Europe, Japan and North America. The two symposium volumes are also significant because substantial portions of the extensive Japanese national research project have been translated into English. The Japanese papers provide an insight to both the magnitude of the technical work being conducted in Japan and the organization of the Japanese research program." Note: The individual papers are also available as .pdf downloads.. Please click on the following link to view the papers available, or call 248.848.3800 to order. SP138

The three-dimensional fabric studied as reinforcement for concrete is a stereo-fabric made of fiber rovings, woven into three directions, and impregnated with epoxy resin. Fiber material, number of filaments, and distance between rovings can be varied easily. Efficient production is also possible, since three-dimensional weaving, resin impregnation, and hardening can all be done by an automatic weaving machine. The authors investigated the flexural and fire-resistance behaviors of three-dimensional fabric reinforced concrete (3D-FRC) toward applying the material to building panels. The fibers studied were carbon and aramid, and the matrix was vinylon short-fiber reinforced concrete. The results demonstrate that 3D-FRC panels have sufficient strength and rigidity to withstand design wind loads, and the fire resistance of 60 min was achieved. The 3D-FRC panels have been used for curtain walls, parapets, partition walls, louvers, etc., and installations amount to 7000 m 2.

Presents information on the development and use of carbon fiber reinforced plastic (CFRP) to strengthen reinforced concrete chimneys, bridge piers, and beams in Japan; bridge beams in Switzerland; and ongoing structural research and use of fiber reinforced plastic (FRP) composite materials to strengthen such structures in the U.S. The concept and equipment for strengthening existing reinforced concrete chimneys by wrapping them with carbon reinforced plastic materials began in Japan. The procedure permitted earthquake-damaged chimneys to be repaired without taking them out of service. Research in Switzerland has led to the use of adhesively bonded sheets of carbon reinforced plastic laminates to strengthen existing bridges. This concept is an extension of use of bonded steel plates to strengthen many types of structures throughout Europe. Research, development, and some use of these techniques has been done in the U.S.

FRP are new materials for structural engineers. Therefore, an overview on the important fiber properties, matrix resins, and composite elements becomes necessary to show the assets and drawbacks of FRP and to illustrate their potentials and limits. Besides several other fields, concrete prestressing seems to have become a promising field of application of FRP. In prestressed concrete construction, high strength and good corrosion resistance of FRP can be utilized optimally. In this field of application, FRP can compete with prestressing steel, especially in such cases in which the corrosion protection of prestressing steel becomes expensive or remains tarnished by residual risks. The post-tensioning of concrete structures requires anchorages with a high mechanical efficiency. The main avenues of development are discussed, and the necessary future research is outlined.