International Concrete Abstracts Portal

"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

Utilizing fiber reinforced plastic (FRP) reinforcement for concrete guideway structures in a superconductive magnetically levitated train system is desirable because FRP reinforcement is diamagnetic. For the design of guideway structures using FRP reinforcement, performance of structural reinforced concrete (RC) and prestressed concrete (PC) members must be understood. Flexural behavior of these members can be predicted by conventional design procedures, taking the mechanical properties of FRP reinforcement into account. However, shear-resisting behavior of RC and PC members has not yet been clarified, for the following reasons. 1. Unlike flexural behavior, shear-resisting behavior is complicated. 2. An experimental equation for shear capacity of RC members using reinforcing steel does not appear to be applicable, since such mechanical properties as Young's modulus and elongation are different from those of reinforcing steel. Under these circumstances, the authors carried out a basic experiment on shear capacity of rectangular beams using FRP tendons and FRP shear reinforcement. As a result, the following factors are elucidated. 1. Shear capacity of RC beams without shear reinforcement can be predicted to some degree by taking into account the tension stiffness of FRP reinforcement. 2. It seems possible to predict contribution of prestress to shear capacity from decompression moment. 3. Contribution of FRP shear reinforcement to shear capacity is smaller than the value calculated by truss analogy. The reasons seem to be related to experimental results showing that the maximum strain value of FRP shear reinforcement at shear failure is smaller than the elongation of FRP reinforcement.

Post-tensioning of concrete members is a promising field of application for FRP tensile elements. The high tensile strength and good corrosion resistance of FRP can be utilized to compete with prestressing steel tendons. To be able to compete successfully, suitable anchorages for FRP need to be developed. The interactive process of experiments and theoretical models for the development of tendon-anchorage assemblies with high mechanical efficiency is demonstrated. This process is then illustrated for a resin-bonded GFRP anchorage.

The permissible crack width of concrete members reinforced by reinforcing steels is generally determined by the durability of the member based on reinforcing steel corrosion. However, since FRP reinforcement does not corrode by rusting, another factor should control permissible crack width for FRP reinforced structures. Paper examines permissible crack width of FRP reinforced concrete members in terms of the esthetics of external appearance. As cracks are wider, appearance deteriorates. Since esthetic evaluation is subjective, the authors used a questionnaire survey to gather information from experts. The surveys were completed by members of the JSCE Research Subcommittee on Continuous Fiber Reinforcing Materials. After reviewing a statistical analysis of the results, the authors offer estimates for permissible crack width of FRP reinforced concrete members.

Presents the test results on fundamental mechanical properties of several kinds of continuous fiber bars. Three kinds of fiber materials (carbon, glass, and aramid) have been used. The shape of the deformed bars differed and the diameter was approximately constant (8 mm). Tensile strength, Young's modulus, tensile creep, and pullout bond strength were tested. The main results were that Young's modulus of carbon fiber bars is about two-thirds that of Young's modulus of steel bars, whereas that of glass fiber bars and aramid fiber bars are nearly one-third that of steel bars; also, the initial slip bond stress and maximum bond stress were more likely to differ with the shape of the continuous fiber bars than with the kinds of fiber materials.