Present state of the asset management is summarized from the viewpoint of civil engineering technologies where problems of the asset management are pointed out. Firstly, the background of the asset management is described based on the necessity of the management for numbers of structures. Next, the outline of the asset management is introduced with focusing on its definition and positioning, the indices to the investment judgment and the probability-based mathematical models. In addition, the relationship between management and maintenance, and the role of civil engineers' skill and technologies for maintenance in the asset management are discussed. Finally, analytical studies are made for the practical models of the asset management for road bridges in Aomori Prefectural Government, Tokyo Metropolitan Government, Yamaguchi Prefectural Government and Expressway Companies. Based on the review and analysis, the future of the asset management is discussed.

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The purpose of the present study is to obtain the fundamental properties of the connecting structure between the micro pile and pre-cast concrete member. Some fundamental experiments were conducted by using the full scale test specimens, i.e. bending momet test, pull-out test and alternating loading test. In the bending moment test, the flexural strengths were investigated by using RC beam embedded with the steel sleeve. The pull-out test and the alternating loading test were conducted with the experimental parameter of embedment length of micro pile.

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Kobe Airport was constructed on the man-made island located at off shore of Port of Kobe. During the reclamation work periods, the advanced quality control system for density control was adopted to deal with its rapid construction and its huge scale of the work. The advanced quality control system consisted of improved RI method and the new construction management system that used GPS and the acceleration meters mounted on earth-moving machinery. Landfill material used for the construction was procured from inland area near island. It was mainly consisted from mudstone contained in Kobe layers. Mudstone has low durability and high compressibility. The material loses strength at high moisture content during the embankment process such as spreading and compaction. Ground stabilization technique for sub grade soil using blast furnace slag improved its trafficability and compaction ratio with reducing the amount of settlement due to consolidation.

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The present report is an attempt to decide on the policy in order to introduce a new method of premeditated maintenance and management of bridges under Yamaguchi Prefectural Government (YPG) control. Indispensable data was selected in order to develop a bridge maintenance plan. Bridge inspection manual was established in order to inspect all the bridges under prefectural control regularly. And Method of deciding the order of priority about bridge repairing, in the limited budget of maintenance and management of bridges, was decided. And the data base system and support system for inputting bridge inspection data were developed.

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In order to develop a rational and economical shotcrete for repairing and reinforcing of existing concrete structures, the method mixing Polyvinyl Alcohol (PVA) short-fiber into a shotcrete applied for protecting rocky slopes was proposed and experimental study for improving the workability was conducted varying mass of cement, silica fume, and PVA short-fiber. From this study, it was confirmed that: (1) rebound ratio of shotcrete and residual ratio of short-fiber can be improved setting mass of cement and replacement ratio of silica fume to mass of cement so as to be around 430kg/m³ and 10 %, respectively; and (2) the proposed shotcrete can be applied in not only lateral but also overhead operation.

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A simple and low-cost monitoring system, namely TIMS (Train intelligent monitoring system) that can be installed in ordinary trains is developed to inspect conditions of the railway track frequently. The accelerometers and GPS are installed in trains. In the system, train position is identified using GPS and train velocity record, and acceleration records of trains by separate measurement are adjusted by a dynamic- programming-based matching method. The field measurements were carried out in local railways and we confirmed high correlation between the train acceleration and track irregularity.

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The purpose of the present study is to obtain the fundamental data for mix design of High Volume Fly Ash concrete. We conducted compressive strength test by employing HVFA concrete which replaced with 50 to 70 percent of fly ash to cement-volume of normal concrete. The experimental results indicated long term strength contribution by Pozzolan reaction by fly ash even in such HVFA concrete. The conversion rate indicated over 100 percent to mass of cement at the age of 364 days, higher strength contribution of HVFA concrete was confirmed from the experimental investigation.

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In this paper, with a recognition that responsive services of road maintenance are important as well as scheduled/planned services, response time as a performance indicator for responsive maintenance is discussed. This indicator is classified as a service-output indicator. Current status of standards and purposes of this indicator mainly in U.S.A. is surveyed. It is shown that this indicator is put to practical use for administrative rules, contract conditions or communications between administrators and residents. It is clarified that improvement of this indicator is effective for rise of customer satisfaction.

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To reduce uncertainties in the safety assessment of the disposal system for long-lived radioactive waste, cement was developed which generates leachates with a lower pH than that of ordinary cement paste. This cement is termed “low-alkaline cement”. Large amounts of pozzolans were used to produce the low-alkaline cement with ordinary Portland cement. Silica fume was found to be an effective pozzolans to reduce pH, but the needed large amount of silica fume reduced the workability of fresh concrete. Therefore, the authors also used fly ash with silica fume, to develop more workable low-alkaline cement, termed high-volume fly ash silica fume cement (HFSC). Two types of HFSC developed showed high compressive strength, smaller drying shrinkage and lower temperature rise than that of ordinary Portland cement. It was confirmed that HFSC could be used as self-compacting concrete. Therefore they can be applied as either structural or backfilling concrete in the disposal system.

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