The optical fiber sensor is noticed from that the easily wide measurement sensor itself serves as a transmission division is possible, that the real-time measurement is possible and that it does not receive the effect of the thunder as soundness monitoring technique of the structure. In this paper, technique and principle of the optical fiber application sensor for strain measurement are introduced. And, the monitoring technique of concrete structure using these sensors is concretely described referring to past research.

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This report reviews data on struetural characteristics of High-rise buildings in Japan. These data were shown in the Building Letter No.1 (1967) -No.427 (2001.1) published by The Building Center of Japan-BCJ. In Japan at present RC High-rise building (Shiodome H-block, 2000 year) reached 56 stories with high strength concrerte 100 N/mm² and high strength steel bar USD 685.

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The third revision of Architectural Standard Specification “JASS 5 N, Reinforced Concrete Work at Nuclear Power Plants”, was published in 2001 by the Architectural Institute of Japan. This revision was made in order to keep up with the progress in technical research and with advances in materials, as well as to keep the compatibility with JASS 5, Reinforced Concrete Work, which covers reinforced concrete buildings in general and was newly revised in 1997. The contents of the revised JASS 5 N were introduced. Section 2 “Performance Requirements of Structures and Members”, section 11 “Cold Weather Concreting” and section 12 “Hot Weather Concreting” were newly established, and durability design strength, low heat portland cement, superplasticized high-performance concrete are newly defined, as well as the revision of correction values of concrete strength “T” and “S” and the range of design strength for high-strength concrete.

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Elastic-plastic behaviors of steel reinforced concrete (SRC) beam-columns under earthquake loading were evaluated well by skeleton curves consisted of the following four points : happening point of transverse tension crack of concrete, flexural yield point, maximum strength point and maximum deformation point. Dimensions of encased steel, strength of materials, hoop ratio and axial load ratio affect the behaviors of beam-columns. In this paper, it was studied by an experimental study and a numerical analysis that quantitative difference of those parameters effects on behavior and skeleton curves of SRC beam-columns encased simple H-shaped steel, and formulae of hysteresis characteristic of SRC columns under earthquake loading were proposed.

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This reports present the investigation of choride-induced damages on NOHO Bridge. This Bridge was constructed 22 years ago as a type, of PC bridge under marine enviroment connecting two islands. The investigation shows the great amount of chloride penetration causing severe chioride-induced damages. It should be noticed that low water-cement ratio such as 38% was used for the concrete and hight compressive strength was obtained.

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For the purpose of selecting proper materials for the repair of concrete structures damaged by both ASR and freezing under the influence of de-icing salt, the examinations on the performance of coating materials by the indoor and outdoor accelerated tests with spreading salt water on concrete specimens with reactive aggregates were executed. As the result, the 10 coating materials respectively showed different level of performance in every condition and it has been clear that the penetrability of water through coatings related to the control of ASR, and the tendency of participation depend on the environmental conditions of the concrete structures. Moreover, a few characteristics of the coatings and the information on the performance tests of coating materials have been gained.

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An adequate evaluation of the current state of RC structure for deterioration, and the deterioration prediction in the future should be necessary in the maintenance of RC structure. And to maintain the performance of the structure, RC structure should be repaired and be reinforced to the appropriate time by an appropriate method. However, RC structure is repaired often when the crack is caused in the concrete structure without considering the required performance of the structure. If the load performance of the structure can be maintained even if the crack is caused at RC structure, the repair time can be delayed, and the repair cost can be reduced. Then, the load capacity evaluating method of the reinforced concrete structure under the chloride deterioration environment was examined, and the model by which all processes from the occurrence of the crack with the chloride ion to the yield strength decrease could be evaluated was proposed. This system gives information of the current and the future assessment for the chloride deterioration environment based on the proposed model. Moreover, this system is useful for the setting for appropriate repair time in consideration of the performance demanded of the structure.

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