[in Japanese]

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 Combined degradation process of concrete by chloride penetration and carbonation is a common situation and it may result in a sever damage of reinforcement in concrete because chloride ions bound by cement hydrates become free after carbonation and concentrate at the carbonation front. In order to simulate these complex phenomena, the authors are developing a numerical calculation code based on a multi-species diffusion model and on a chemical equilibrium model. The validity of the model will be examined by comparing with elements distribution measured quantitatively by using EPMA that is also now being developed by the authors. In this paper, concepts of modeling this complex combined process are explained. Especially modeling of chlorides binding by AFm and C-S-H and chloride release by carbon dioxide penetration is discussed chemically. As an example of this combined process, carbonation experiments were carried out for chloride containing concrete specimen. EPMA shows a peak behavior of chloride concentration at the carbonation front quantitatively. Finally the outline of the advanced model developing is introduced and one calculation example reproducing a peak behavior of chloride concentration is indicated.

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 The grinding aid-diethylene glycol (DEG) affects the handling performance of cement powder after being ground and cement quality. However, DEG content in cement and its quantitative analysis method are not made clear. This study determined the DEG content in cement by the gas chromatograph, and it examined the extraction condition of DEG from the cement. Extraction of DEG from cement increased by optimization of the solid-liquid ratio and addition of lithium chloride, heat with shaking, etc.. Extraction ratio of DEG in the optimizing condition was 75% of the amount contained in cement. However, this extraction ratio was not affected by the addition of DEG and the grinding condition of cement. In the cement that ground at the plant, the part of added DEG had been volatilization or decomposition under grinding by the volatilization, and the proportion is different between plants. In addition, it may be concerned in the difference between initial mortar compressive strength.

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 Acoustic monitoring of tendons has recently received considerable attention as a practical technique to maintain efficiently several bridges in Europe and North America. In acoustic monitoring, the acoustic emission (AE) signals generated by the wire fractures are captured by an array of sensors that are attached to the structure. Each of the sensors is capable of locating the source of the event. In the case of prestressed concrete (PC) bridges, it is necessary to be able to accurately and effectively detect the AE signals in the presence of ambient noise such as those present in traffic conditions.
　The AE signal caused by wire breakages in a PC hollow girder, produced in accordance with JIS Standards, have been investigated using an experimental device that utilizes the original acoustic emission sensor. In order to understand the propagation characteristics of wire fractures, the decay distance of the wave's amplitude and the frequency spectrum of each wave have been studied. It was found that there was a wide range of values for the wave's amplitude in each wire.
　In the same way, existing PC hollow slabs in service were studied in order to examine traffic noise. Notably, large traffic noise amplitudes were occasionally discovered to occur at the joints of the PC slab.
　By calculating the root mean square value of each wave, it is possible to separate the tendon breakages from the traffic noise, provided that the sensors are carefully placed with appropriate spacing between them.

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 The Cisokan Project in Java Island was the first project for Pumped Storage Hydropower with maximum output 1000MW in Indonesia. The dam for this hydropower was planed as RCC (Roller Compacted Concrete) gravity dam. In Java, there was no experience for RCC dam.
　The author totally supervised the design of the RCC including selection of materials, making mix and procedures of placing.
　This article introduced that the author's experiences through the project were assorted into follows,
　　・The outline of project
　　・The circumstance of concrete materials in Indonesia
　　・Thｓe development of rich paste RCC
　　・The development of procedures for joint construction using maturity index
　　・An uniqueness of concrete related in Indonesia

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 To apply the limitation of amount of material passing standard sieve 75μm, micro particles, in aggregates as 1% for crashed coarse aggregate and 7% for crashed fine aggregate on limestone aggregate can be considered to be unreasonable by the following results from the study on the effect of micro particles in limestone aggregate on the properties for concrete.
(1) Micro particles in limestone aggregate produced from crushing and transportation is almost the same as a limestone powder additive for concrete.
(2) The micro particles increasing effects on loss of slump indirectly. It leads to loss of entrained air therefore it leads to loss of slump. A proper content of the micro particles in limestone crushed sand can be more than 10% to improve plasticity for concrete.
(3) The micro particles increasing leads to reduction of bleeding, acceleration of setting time, enhancement of strength.
(4) The micro particles increasing dose not deriver a harmful effect on drying shrinkage and durability to freezing and thawing.

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 Our Information System "Research & Development Knowledge Portal" (hereinafter called RDKP) since April 2003 has provided all kinds of information to major affiliated companies as an internet tool to increase our groups' capacity of technological development.
　In the office, all employees can use this system with groupware "Lotus Notes^Ⓡ".(hereinafter called RDKP for Notes)
　Both RDKP and RDKP for Notes allow users to refer information directly, but the former has a search function, while the latter lacks. RDKP for Notes cannot perform batch searches for all contents in RDKP and multiple searches for each content because it has only a standard equipped search function of lotus notes.
　For users of RDKP for Notes in the office, this is an introduction of a new system "RDKP Plus!", which enables multiple searches in not only contents of RDKP but also other in-house contents (database).

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