First International Conference on Self Healing Materials was held in the Netherlands in April 2007. A technical committee about self healing concrete was established in JCI in 2007. A technical committee of RILEM has also started its activities on Self healing concrete. In this report, the latest movement of research on self healing concrete in Japan and in foreign countries is explained. Our way of thinking about the definition of technical term such as self healing and self repairing is exhibited. Useful information obtained in the first international conference, the research activities of JCI and RILEM technical committees, and some latest research topics are explained.

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In 1985, the Research Committee on Polymers in Concrete in the Society of Material Science proposed “Recommendation for structural design of polyester resin concrete (draft)”. Then, many types of polymers (e.g. unsaturated polyester resin, epoxy resin and acrylic resin) have been used as matrix of polymer concrete. In addition, most structural design concept in civil and architectural fields has been changed to performance-based design. In order to apply the polymer concrete to various kinds of applications appropriately, the recommendation was revised in 2006. This paper introduces the fundamental material properties of polymer concrete and the typical examples of applications briefly, and also presents the contents of “Recommendation for structural design of polymer concrete (draft)”.

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When use molting slag as concrete aggregate, a problem of the expansion by a quality fall by particle size/the surface property of the particle and the metal aluminum component occurs. This study examines expansive melted slag of waste were treated with chemical, and discusses the utilization as fine aggregate for concrete. It was verified that the concrete using unexpanded treatment melted slag of waste has good quality, when fresh and when hardened and durability. Furthermore that unexpanded treatment was availed concrete of steam curing.

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Near-infrared spectroscopy is expected as a useful technique for a concrete deterioration diagnosis Deteriorations on the concrete surface could be detected non-destructively in a short time by this technique. However, the detection varies with the complex material composition and environment due to exposed conditions. Therefore, the obtained spectroscopy analysis should be considered the environmental effect of concrete surface, especially such as carbonation. In this study, in order to improve the problem, Chemometrics technology is applied as a new diagnosis method. Chemometrics : method is known as a technique in the field of chemical analysis. This method is used for analyzing a huge parameter such as chromatography and mass spectrometers. The result in the inspection for concrete diagnosis from the spectral analysis suggests the possibility of practical use. In the case that the carbonation and the penetration of the chloride ion occur on the concrete surface at a time, Chemometrics method is confirmed to detect the amount of chloride ion accurately. After all this method is expected as a normal non-destructive test for the inspection of the concrete diagnosis in the near future.

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As ultra high strength fiber reinforced concrete (Ductal) is new generation concrete material possessing high strength, high ductility, high fluidity and high durability, it is possible to drastically reduce the dead weight of the bridges made of Ductal compared with those made of ordinary concrete. The authors have been challenging the technical development and have accomplished a 40 m long mono-rail girder based on the accumulated design and construction know-how for recent five years. The developed long span girder is consisted of six pre-cast segments and its cross section is a box shape. The construction and structural safety performance have been verified before the construction of a 40 m long mono-rail girder, through a series of experiments and FEM analyses such as a fundamental joints tests, fabrication tests using a 10 m long mono-rail girder and loading tests.

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[in Japanese]

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[in Japanese]

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