Outdoor exposure tests of fly ash concrete have been carried out in various places around Japan since 2009, and the durability of the specimens has been monitored for 10 years to assess how differences in exposure environment would influence the long term physical property and durability of fly ash concrete as well as the degree of pozzolanic reaction of fly ash. This paper reports the changes in physical properties observed during the first seven years and the pozzolanic reaction degree after seven years of exposure. The durability of fly ash concrete was found to be improved as the pore structure became complicated due to pozzolanic reaction. It was also found that there was no difference in the pozzolanic reaction degree of fly ash in concrete between the different exposure conditions after an adequate time period of seven years.

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 The use of ultra high strength fiber reinforced concrete (UFC) has been increasing since the publication of the recommendations on design and construction of UFC structures by the Japan Society of Civil Engineers in September 2004. UFC is a unique cementitious composite with a high tensile strength which enables concrete structure designs without reinforcing bars. Its durability is also very high compared to conventional concrete. UFC has been applied mainly to bridges, taking advantage of its high strength. Sakata-Mirai Footbridge completed in October 2002 was the first bridge in Japan constructed with UFC. In this paper, the durability and the mechanical properties of the 15 year old UFC bridge have been studied by using the specimens exposed to the field inside the box girder. The main results obtained are as follows: (1) The compressive strength of the field specimens has gradually increased until the age of 15 years; (2) The flexural strength of the field specimens has increased almost linearly until the age of 15 years; (3) Chloride penetration depth after 15 years of exposure was less than 3.0mm from the surface; and (4) Delayed reaction of unhydrated cement grains richly contained in UFC with external water allowed the initial cracks to close gradually.

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 Pt–Rh/CeO₂/Al₂O₃ was successfully synthesized by a hydrothermal method, and its chemical and physical properties as well as catalytic activity were evaluated. Pt–Rh/CeO₂/Al₂O₃ was also prepared by a conventional impregnation method synthesis method for comparative purposes. The Pt–Rh/CeO₂/Al₂O₃ synthesized by the hydrothermal method was found to comprise hollow CeO₂ nanorods coated with nanoparticle arrays, with the CeO₂ surfaces being selective supports for Pt and Rh. Furthermore, although the light-off temperatures of NO and C₃H₆ were similar between the Pt–Rh/CeO₂/Al₂O₃ catalysts prepared by the two different methods, the hydrothermally synthesized Pt–Rh/CeO₂/Al₂O₃ exhibited a lower light-off temperature of CO compared to the one synthesized by the impregnation method. The hydrothermally synthesized Pt–Rh/CeO₂/Al₂O₃ also exhibited a higher catalytic activity, which was attributed to its better dispersion of Pt and Rh compared to the impregnation one.

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 Mineral fertilizers were prepared using three different types of sewage sludge incineration ash (SSA) and CaCO₃ by means of calcination. The raw mixtures with varied CaO contents were calcined in an electric furnace at different temperatures. To evaluate the fertilizer performance, water soluble SiO₂, citric acid soluble P₂O₅ and mineral composition were analyzed.
　The results showed that the formation process and dissolution behavior of minerals varied depending on the composition of the raw SSA.
　 Calcining higher Al₂O₃ ash with a CaO content increased to 55.0% produced a mixture of gehlenite and Ca_14.92 (PO₄)_2.35 (SiO₄)_5.65, with citric acid solubility of P₂O₅ and water solubility of SiO₂ improved up to 98 and 86%, respectively. Calcining lower Al₂O₃ ash with a CaO content increased to 57.5% produced dicalcium silicate, with both citric acid solubility of P₂O₅ and water solubility of SiO₂ improved to over 98%.
　Consequently, it was found that regardless of the chemical composition of raw SSA useful mineral fertilizers with high solubilities of P₂O₅ and SiO₂ could be obtained by adjusting the CaO content properly.

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 In order to elucidate the particle characteristics affecting the reactivity of fly ash (FA), reactivity of each particle in hardened FA cement and the its influence on the alkali reactivity were analyzed. As a result, in the 6 classes constituting FA, it is 4 classes whose surface is covered with glass, among which the main component of the glass having the largest proportion is Al₂O₃-SiO₂ (AS). Therefore, composed class had an influence on reactivity. Also, it is the sphere reduced specific surface area that most affects the activity index of FA cement, and the influence of the chemical composition of the glass phase is small. Based on the finding that the reactivity of FA varies with the surface area of reacting glass particles, it will be possible to streamline quality control of FA cement by means of characterization of FA.

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 Condition of highly expansive material (HEM) after 14.5 years of service as anchorage in the field was investigated. Depth of carbonation, state of hydration and pore size distribution were analyzed, and observation of the hydration structure was performed. In addition, long-term material durability was analyzed with the focus placed on the relationship between the obtained results and expansive pressure influencing the anchorage performance. The results showed that HEM was still in good condition to exhibit the anchorage performance, as reported previously.
　The present study was a data analysis focused on the state of the hardened HEM. Interesting findings were obtained as follows: 1) Hydration rate of HEM was about 94%; 2) 2% of quicklime was still present in the HEM, suggesting an adequate remaining capacity as anchorage; and 3) Hardened HEM was in constant exposure to high pressure due to the expansive force generated in it and might have a different hydration behavior from the normal cement materials.

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