The microstructure and optical properties of clinker minerals are strongly influenced by the thermal history during kiln firing, which affects their hydration reactivity. Therefore, microscopic observation of clinker microstructure provides essential information for both process optimization and quality control. However, conventional microscopic evaluation relies on visual inspection by skilled technicians, requiring significant expertise and limiting the amount of observation per unit time. This makes online analysis in industrial production difficult. To address these issues, an automated microscopy system using Artificial Intelligence (AI) and image processing techniques has been developed. This paper presents a comparison between evaluations conducted by a microscopy technician and the automated system for clinker samples produced under different firing conditions. The results demonstrate that the system is capable of evaluating belite grain size and color with a level of accuracy comparable to that of a microscopy technician.

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 Since curing temperature significantly affects the strength development of concrete, monitoring of concrete temperature during curing has been widely studied as a useful means for quality control. Wired sensors such as thermocouples are commonly used to measure concrete temperature; however, measurement using wired sensors is often impractical due to the burden of wiring work.
　To address this issue, a curing monitoring system has been developed using a temperature-sensing RFID tag to measure the temperature history of concrete through short range wireless communication without wiring.
　In this study the system was applied to concrete slabs, and temperature measurements obtained immediately after casting were compared with those measured by wired sensors. The results showed that the temperature-sensing RFID tags provide temperature measurement accuracy equivalent to that of wired sensors. Furthermore, the system was also applied to the determination of the optimal timing of early-entry sawing in concrete pavement construction. The maturity calculated from the measured temperature history accurately captured the temperature evolution required for maturity evaluation and enabled rational decision-making for early-entry sawing timing. These findings indicate that the proposed system has strong potential to improve construction efficiency and enhance quality control, especially in paving works requiring strict timing management under practical field conditions without increasing installation complexity.

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 In the geological disposal of high-level radioactive waste (HLW), a clay material called a buffer, usually made mainly of bentonite, is placed around the waste. The buffer is expected to serve several important functions, including limiting radionuclide migration, maintaining mechanical stability, and providing hydraulic control. However, in the environments with abundant groundwater, like Japan, bentonite may be eroded and transported by water flow. In particular, piping erosion can occur at the interface between the bentonite and the disposal pit wall, where water forms channels along the bentonite surface and carries the material away. This phenomenon is a significant concern because it may degrade the performance of the buffer.
　In this study, we focused on measuring piping erosion in bentonite using X-ray computed tomography (CT) and spectrophotometry. X-ray CT was used to visualize the internal structure of the bentonite, as well as the piping channels formed along the bentonite surface, while spectrophotometry was used to measure the amount of bentonite in the outflow water.
　The results showed that an index representing how easily bentonite is eroded (the apparent erosion rate constant) remained almost constant even when the water flow rate changed. This suggests that the amount of bentonite erosion caused by piping can be estimated using the index. Furthermore, this study demonstrated that X-ray CT would be a highly effective non-destructive tool for understanding bentonite behavior in buffer materials and providing time-dependent data.

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 In response to the growing demand for environmentally friendly concrete in the construction industry, Taiheiyo Cement has been selling Portland blast-furnace slag cement type C since September 2025. As part of preparation for the launch of the product, technical documentation was developed to promote its proper and effective use.
　This report presents the results of evaluations of the fresh properties, strength characteristics, and various durability aspects of concrete produced using the Portland blast-furnace slag cement type C (BC) product of Taiheiyo Cement.
　The admixture dosage required to achieve the target slump and slump flow for BC-based concrete was found to be within a standard range at all ambient temperatures, being lower than that required for concrete using ordinary Portland cement(N).
　Although the compressive strength was lower at early ages compared to N-based concrete, the BC-based concrete showed greater long-term strength development. In addition, higher ambient temperatures resulted in greater 7-day compressive strength. The increase in compressive strength after 7 days was similar between 5°C and 20°C, but was significantly smaller at 35°C.
　Regarding the durability, the BC-based concrete exhibited a lower mass loss ratio than that of N-based concrete in drying shrinkage tests, and its length change at 26 weeks of drying was equal to or smaller than that of N-based concrete. Furthermore, the BC-based concrete was found to have significantly higher resistance to sulfuric acid compared to N-based concrete.

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 Tiled exterior walls are widely used as a building finish. While periodic inspections to detect debonded tiles are required to prevent accidents caused by tiles detachment due to aging, building managers face a significant burden in terms of inspection costs and coordinating with tenants.
　The “Wall Survey System^Ⓡ” is an exterior wall inspection technology using unique devices. Wall survey robot is suspended from the roof to scan the exterior wall surface. Wall survey rod can be extended to access exterior walls up to 7.5 meters above ground level. Both devices are equipped with a mechanism that uses a freely rotating striking unit to strike the wall surface continuously and efficiently.
　This report presents a case study evaluating the accuracy of detecting debonded tiles in existing buildings by comparing the proposed method with conventional manual tapping.
　In July 2025, the “Wall Survey System^Ⓡ” was certified by the Japan Association for Architectural Disaster Prevention's technical certification system as having the same level of accuracy as conventional manual tapping, making it eligible for use in mandatory periodic inspections (inspections under Article 12 of the Building Standards Act).

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