In this paper, the relationship between chloride ion diffusion coefficients measured by ponding and migration test was theoretically considered in order to predict the amount of chloride penetration into concrete using those measeured diffusion coefficients. As the result, the theoretical consideration shows that the prediction method of penetration under the condition of linearly chloride binding isotherm is different from that method under the condition of non-linearly chloride binding isotherm. In addition, chloride binding capacity is estimated by theoretically calculating from the diffusion coefficients measured by ponding and migration test under the condition that the chloride binding isotherm is linear. And the capability of predicting the amount of chloride penetrattion by using the value of chrolide binding caracity and migration coefficient is clarified.

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 Many studies to clarify the mechanism, that hydrated cement maintains high pH condition for a long period have been reported. However, due to the lack of solid phase analysis, they do not related to the dissolution process of cement hydrates. We have performed a permeability test in which centrifugal force is used to percolate pore water and have studied the change of aqueous chemistries and that of the solid phase simultaneously in order to investigate the dissolution phenomena of hydrated cement.
　The dissolution process of the hydrate phase agreed with that of the results of the other dissolution tests that is dissolving in the order of Na₂O and K₂O Ca(OH)₂ and C-S-H gel. Accordingly, it was ascertained that this permeability test was carried out under the equilibrium condition between percolated pore water and hydrates. It was confirmed that pore volume increased by the dissolving of hydrates and pore structure clearly changed. The relation between the volume of percolated water and its chemical composition was evaluated by the model coupling transport and chemical equilibrium calculations. The calculated calcium and silicon concentrations of the percolated water were in good agreement with the experimental values, and thus, we were considered that this model was useful for evaluating the behavior of cement hydrates dissolution.

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 This report describes the field survey on durability of roller compacted concrete pavement by the use of limestone as aggregates which was constructed in December 1988. The following results are observed in this study:
(1) The performance of pavement has been maintained for fourteen years.
(2) The compressive strength of pavement determined by core specimens has not decreased for fourteen years.
(3) The changes in surface smoothness and rutting of limestone concrete for fourteen years is larger than those of sandstone concrete.
(4) Longitudinal cracks and potholes are observed in the pavement. This is likely due to construction defects such as poor compaction and thin pavement sections.
(5) The coefficient of linear expansion of limestone concrete is only 60% of that of sandstone concrete. As a result the thermal stress of the pavement is reduced.
　This is the reason why the durability of the pavement under cyclical temperature loading is improved.

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 In this report, the influence of mix proportion of cement pastes on shrinkage was investigated. These pastes were composed of four types of cement(ordinary Portland cement, high-early-strength Portland cement, two types of belite cement), powder admixture(lime powder, silica fume) and additive agents (expansive agent, shrinkage reducing agent, forming agent). The results were obtained as follows:
(1) The shrinkage was separated into three types: two phases of chemical shrinkage (primary chemical shrinkage and secondary chemical shrinkage) and drying shrinkage. Primary chemical shrinkage was high compared to other shrinkage.
(2) Belite cement had beneficial effect in reducing of secondary chemical shrinkage and drying shrinkage. However, the amount of primary chemical shrinkage tended to increase with using belite cement.
(3) Combination use of expansive agent and shrinkage-reducing agent had beneficial effect on reducing of secondary chemical shrinkage at extremely low W/P.
(4) Multiple regression analysis of the test results showed that the amount of shrinkage could be predicted from mix proportion of cement paste.
(5) According to optimization of the mix proportion for shrinkage deducing, chemical shrinkage and drying shrinkage were improved dramatically.

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 A new numerical evaluation for risk of recyclable resources was proposed in order to establish a risk assessment procedure that is suitable for recyclable resources received at cement plants. A conception of "dummy point" was adopted in order to make possible a comparison of risks using different factors (hazard, concentration, working environment and working method) concerning harm, like the presence of harmful chemicals, on oxygen shortage, explosive gas, or injury by sharp things. The relationship between risk point and the level of protection was shown by comparing risk points with numeric values that expressed the degree of harm.

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 The thermal expansion behavior of ceramic composites was investigated to obtain ceramics that has zero thermal expansion coefficient at room temperature (296K) and high elasticity. The thermal expansion coefficient was controlled by making a composite if two types of ceramics, which have either positive or negative thermal expansion coefficient. In this study, lithium aluminum silicate (LAS) was selected as the negative thermal expansion ceramic.
　LAS and silicon nitride were mixed and sintered under N₂ atmosphere. No phases were detected by the X-ray diffraction, except for LAS and silicon nitride, in the sintered material. The thermal expansion behavior was investigated by the laser-interference method. The rate of liner expansion versus temperature showed a parabolic curve. The thermal expansion is zero at the local minimum point of the linear expansion ratio curve. The temperature of the local minimum point became lower as the ratio of silicon nitride increased, and the local minimum point reached 296K at 40wt% of silicon nitride. The Young's modulus of this composite was as high as 168GPa.

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 The 3rd Session of the Conference of the Parties to the United Nations Framework Convention on Climate (COP3) Kyoto Protocol was ratified in December, 1997 when the consideration to conservation of energy rises caused by global warming in the world scale. Because a further CO₂ reduction in industry, transportation, and the public welfare each section comes to be going to be demanded in the future also in Japan, we will take up the External thermal insulation components system (outside insulation) for the reinforced concrete (RC) construction, and will discuss about an excellent feature on both sides of the living environment and the global environment like a dramatic effect to the decrease of healthy damage and frame concrete durability improvement. This thesis introduces the domination of this outside insulation industrial method and the view in the future basing the energy conservation　circumstances inspection result of Sweden and Germany which are advanced countries in insulation, and considering the climate, manners, and the weather situation in Japan.

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 Recently, requirements for concrete technology have been diversified with progress in the methods of structural design and construction technology.
　In 2002, Standard Specifications for Concrete, published by Japan Society of Civil Engineers, were all revised by a new concept of Performance-Based Design instead of the material specifications. According to this new guideline, providers for construction　materials are required to prepare the technical proposal that the materials should meet the requirements on the structure clearly.
　For one of this purpose, we propose new technical reports "Concrete Solution Menu" for customers. As the customers will require the technical information on the construction materials through the Internet, material providers will be requested to respond it quickly.
　This report describes a new business model to propose the high quality concrete utilizing Information Technology (IT).

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 TAIHEIYO CEMENT CORPOLATION Research & Development Center is promoting the research and development support to enhance the business for companies in TAIHEIYOCEMENT group.
　This support services were provided using portal site called RDKP (Research & Development Knowledge Portal) on the internet and released on April 2003. RDKP has more than ten data bases covering cement, concrete, eco-environment and advanced ceramics, and THD (Technical Help Desk). THD delivers a solution for technical subject and also has a function of interchange for technology in TAIHEIYOCEMENT group companies.
　We introduce the outline of content in RDKP and operation system.

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