As described herein, a multi-species mass transport model has been developed. It can predict time-dependent of variation of both a pore solution and solid-phase composition due to the mass transport into hardened cement paste. Most previous multi-species models were based on the Poisson-Nernst-Planck theory and did not involve modeling of the chemical process. For this study, it has been coupled to a thermodynamic equilibrium model. By coupling it with a thermodynamic equilibrium model, the multi-species model can simulate myriad phenomena related to hardened cement paste: (i) variation in solidphase composition when using cement of different types; (ii) physicochemical evaluation of steel corrosion initiation by calculating the molar ratio of chloride ion to hydroxide ion[Cl^-]/[OH^-] in the pore solution; and (iii) complicated changes of solid-phase composition resulting from penetration of mineral salts during marine seawater exposure. Those phenomena in concrete are predictable using the coupled multi-species mass transport model and the thermodynamic equilibrium model described herein.

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 Low-alkalinity cement based on sulfoaluminate-belite clinker was produced experimentally. Fresh properties and hardening behavior of mortar and concrete were examined using this cement. Generally, development of compressive strength was good, but the early stage of strength tended to decrease when a large quantity of retarder was used. Additionally, results clarified that the C/W and compressive strength did not have linearity relations after the age of 7 days. Because of replacement of some cement with fly ash or limestone powder, less strength was gained, but practical strength was secured. Additionally, reduction of the adiabatic temperature rise and improvement of fluidity of concrete was confirmed. Regarding volume change, shrinkage occurred immediately after setting, but it soon changed to expansion and was maintained to the age of 10-30 days. At 1 year, displacement from the base point was approximately zero when using standard grain size cement; shrinkage of 100-150×10^-6 was observed when using fine cement.

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 This paper evaluates the fresh properties, compressive strength and shrinkage of shrinkage controlling concrete (SCC), produced in two ready-mixed concrete plants, corresponding to special grade concrete standards (drying shrinkage strain: 500×10^-6 and below) as outlined by Architectural Institute of Japan "Recommendations for Practice of Crack Control in Reinforced Concrete Buildings (Design and Construction). " The SCC was produced in two plants over three seasons (Spring, Summer and Winter) using a shrinkage reducing chemical agent, expansive admixture, and limestone coarse aggregate with a water-to-binder ratios of 35.1-55.6%. Fresh properties achieved the target performance by adjusting the dosage of chemical admixtures during each season. The properties needed for the strength design, which are the relation between binder-to-water-ratio and strength as well as the corrected value based on the relation between strength and average temperature, were derived from data obtained under various conditions. The shrinkage strain satisfied the limit value of JASS special grade standards. The investigation results demonstrated that SCC is applicable in a practical and realistic manner.

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 Because the fishery industry yields scallop shells as waste products in great quantities, we wish to explore disposal methods of these shells to reuse them as a raw concrete material. We seek to use more finely crushed shells in concrete per unit volume, while minimizing impacts on concrete quality. We examined influences on the properties of concrete by the fineness modulus of the crushed shells. A reasonable range of fineness modulus was found that satisfied both the crushing efficiency of shells and concrete performance. Additionally, we compared the strength and durability of concrete that incorporated crushed shells at 400kg/m³ with concrete that did not contain shells. Results confirmed that the shell-containing concrete provided similar performance to that of regular concrete.

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 Generation of electricity can be accomplished using a piezoelectric device: mechanical deformation is transformed directly into electricity. That mode of extracting electrical power from the natural environment is now attracting much attention. Looking at the electricity obtained using a piezoelectric device, it is apparent that its produced voltage is high, but the current level is low. Considering this basic characteristic, this type of electricity generation has been used for high-voltage output devices such as ignition device or piezoelectric transformers, and also for other devices that require a high response rate such as acceleration sensors. Therefore, few reports describe its use for electricity generation using natural energy or the use of such generating capacity for supplying power to various devices and equipment.
　This paper presents a description of various technical components in building a wide area sensor network to observe wind velocity using piezoelectric generated power, which is supplied to the network’s wireless transmitter, without commercially supplied electric power.
　We first examined the piezoelectric device’s basic characteristics to investigate it from an electrical generation perspective. We then improved its design and thereby invented a piezoelectric generation mechanic that generated electricity from wind power. This electric generation by the piezoelectric device that we invented was able to supply sufficient power to drive a transmitter that can establish radio communication to 1 km distance away at intervals of a few seconds, when available wind speed of 6.5m/s.

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 TAIHEIYO CEMENT CORPORATION designed a group research and development strategy for Taiheiyo Cement Group that unites the alliance through research and development. In this strategy, an action program was installed in the group to strengthen systems used to research and develop new ideas. The Research & Development Center began Research & Development Knowledge Support, which shared technology throughout the group. As part of this activity, the “Concrete Solution” system, which efficiently proposed concrete technology of Taiheiyo Cement Group, was constructed. Furthermore, to promote the “Concrete Solution” system, technological lectures were held to introduce our technology.
　This report introduces the technological lecture “Taiheiyo Cement Group Techno Forum”, which has the following purposes. It positively proposes the technology that Taiheiyo Cement Group offers to the user. Additionally, the relations of the group are strengthened, and technology development needs are addressed. “Taiheiyo Cement Group Techno Forum” has been held in four areas of Japan: Tokyo, Miyagi, Aichi, and Osaka. Invited guests have included educators, sponsors, design consultants, general contractors, ready-mixed concrete companies, concrete products companies, and thers; about 560 other guests have attended. Future “Taiheiyo Cement Group Techno Forum” events are planned for other areas of Japan.

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