This study examined the influence of air content on the strength activity index test specified in Annex C of JIS A 6207:2016 (Silica fume for use in concrete). The results confirmed that the effect of air content difference on the activity index was greater than that of the flow difference between the reference mortar and the test mortar. Furthermore, an investigation of quality control records over the past five years, conducted in accordance with this Annex, revealed that the air content difference between the reference mortar and the test mortar has been controlled within approximately ±1.0%.

A literature survey was conducted on the transition of standards and test methods of recycled aggregates for concrete. Before the establishment of JIS standards for recycled aggregates, various standards of recycled aggregates had been created by different organizations. However, with the establishment of JIS standards, the standards of each organization have been unified to cite JIS. It appears that overseas standards were not heavily referenced during the development of these standards. Rational and efficient test methods have been developed to evaluate the quality of recycled aggregates. However, there appears to be room for further improvement, particularly regarding tests for impurities.

This study investigated the effects of differences in the main components of curing compounds for concrete on various properties. As a result, no differences in moisture dissipation rate were observed due to differences in the main components of the curing compounds, while a correlation was found between the residue ratio and the moisture dissipation rate. In addition, the effectiveness of curing compounds in suppressing initial cracking of concrete was confirmed. It was also clarified that the effects on bond strength and abrasion resistance vary depending on the differences in main components.

This study evaluates the effectiveness of precut systems for light gauge steel framing and gypsum boards in interior wall construction. By comparing conventional and precut construction methods across multiple floors of a steel-framed office building, the study analyzes labor efficiency, waste reduction, and material logistics. Results indicate that precut methods reduce material waste and improve work consistency. The findings suggest that precut systems can enhance construction productivity and standardization in interior works, with potential as a foundational strategy for future process optimization.

In this report, a questionnaire survey was conducted on factories that have obtained “N(T) Certification,” “N Certification,” or “N+H Certification” in the Prefabricated Construction Materials Association’s “PC Component Quality Certification.” In terms of factory overview, the scale of the factory has increased with the N+H certification, and as a result, the number of mixers has increased and the stockyard area has also become larger. Regarding whether or not heat curing was performed, there was a tendency for responses to heat curing to increase when the component thickness was 300 mm or less, in winter, and when the design standard strength was low.

Three evaluation indexes are introduced for quantitative non-destructive evaluation of anchorage zone of post-installed anchor by using electromagnetic pulse method. One is derived from frequency spectrum in high-frequency band and the other two are from phase spectrum. In addition to conventional indexes, use of the three ones contributes further improvement of evaluation performance.

The purpose of this study was to verify the concentration of asbestos and other fibers generated during cutting and related work with power tools, and to evaluate the effectiveness of dust suppression measures. The research also aimed to provide insights for safer renovation and demolition practices to prevent asbestos exposure. Experiments, including cutting tests, were conducted in an isolated curing area using asbestos-containing finishing coating materials, slate boards, and type 1 calcium silicate boards. The level of asbestos fiber release was measured and compared with findings from previous studies.

Dam-break experiments simulate the sudden release of stored upstream water and its impact on a model. Since the stored water depth is the only adjustable parameter, it is difficult to control the flow velocity and inundation depth. In this study, roughness blocks were installed on the channel bed to regulate the flow, and the effects of their arrangement and height were examined. These blocks reduced the flow velocity, Froude number, and the drag forces on the model. The results revealed that the drag coefficients on the model depended on whether the dam-break flow overtopped or bypassed the roughness blocks.

This paper aims to provide material to assist in the design process. The authors surveyed the literature on aging effects of natural rubber bearings and consider their basic and rupture characteristics. Aging tests were conducted either by real time or by accelerated heating tests. In both cases, the horizontal stiffness of the natural rubber bearings tended to increase with age. Comparing the results of the real-time aging tests and the accelerated heating test, the results were generally comparable after about 40 years of aging. The rupture characteristics, i.e., rupture strain and rupture shear stress, both tended to decrease with age.

The building mass damper (BMD) utilizes part of a building as a tuned mass, achieving a larger mass ratio than typical TMDs, thus enhancing seismic performance. However, effective application in real buildings requires considering various factors beyond TMD theory. This paper initiates BMD design methodology by analyzing seismic response using a multi-degree-of-freedom model with stiffness and damping of the connection layer as parameters. It examines the relationship between response distribution, seismic characteristics, and TMD-derived optimal solutions. Practical design examples and BMD applicability are discussed. The CCQC method is also applied to estimate response values without analysis, evaluating its applicability.

In this report, we investigated the roof damage to wooden house in the center of Sukumo City, Kochi Prefecture, and the toppling of bookshelves and scattering of books at the Sukumo City Sakamoto Library, caused by the 2024 earthquake Bungo Channel. We also conducted interviews with victims of roof damage and staff of the Sukumo City Sakamoto Library. We then analyzed the ground motion observed at the Sukumo City observation point, and analyzed the observed ground motion and the damage to the tile roof of the wooden house, the toppling of bookshelves at the library, and the scattering of books.

This paper reports the results of full-scale experiments conducted to clarify the static friction characteristics of a Spherical Sliding Bearing (SSB). In recent years, the number of seismic-isolated buildings where the wind-induced responses cannot be ignored has been increasing. In the case of SSB, static friction characteristics, particularly the upper limit of static friction force, are important for wind-resistant design. However, few experiments or research have focused on these characteristics. The experiment was carried out by applying a horizontal load at a constant rate to the SSB while it remained at rest, to reproduce the effect of wind-induced loading conditions.

This study verifies the effectiveness of a formfinding analysis method for bending-active latticed kagome shells (ASE&BSE method) using a general-purpose finite element code through model experiments with aluminum. To capture the geometry, 3D scanning and a 3D non-contact measurement system were employed. A novel method was developed to identify member axes from the acquired data. The deviation of the measured geometry of the model from the formfinding analysis results was slightly large in-plane, but sufficiently small in the out-of-plane direction, and it is considered that the formfinding analysis method has a reasonable degree of accuracy.

This paper presents the effect of cumulative damage on the performance degradation of wooden houses subjected to multiple earthquakes. Regarding the residual seismic capacity ratio R in the post-earthquake damage classification guidelines, time-history response analysis confirmed that the guideline formula generally provides a safety margin for various shear walls. The effects of damage sustained in the previous year’s earthquake were examined during the 2024 Noto Peninsula Earthquake. The guideline’s formula of R primarily explained the additional strength required to prevent collapse.

Recently, seismic diagnosis has been carried out to ensure the safety of important cultural properties (buildings) during an earthquake. These seismic diagnosis data from past implementations have been accumulated. This study aims to clarify the current state of seismic diagnosis for important cultural properties (buildings), especially for traditional wooden buildings by literature survey. Analyzing the structural characteristics indices, both residential and temple/shrine buildings showed a tendency toward low seismic performance. Then, we analytically examined the factors that caused differences in the seismic results, focusing on the base shear coefficient, representative height, amplification factors of acceleration and the skeleton curve.

This study examines the structural performance of a timber carport frame with knee braces. The wooden columns are inserted into aluminum square columns embedded in the frame foundations. Full-scale lateral loading tests of a timber carport frame demonstrated stable load resistance and ductile behavior even under large deformations, though local connection damage occurred. Comparisons with frame analyses indicated that stiffness was overestimated because the models assumed pin joints, neglecting initial slip and embedment observed in the experiments. The results confirm practical applicability for snowy regions.

In this study, adhesive post-installed anchor specimens with ribbed bar as a variable were fabricated, and without using strain gauges, the strain distribution of the anchor bars under tensile loading was measured using neutron diffraction. The objective is to clarify the bonding zone of the anchor bars. As a result, it was found that the plain bar portion at the loaded end does not provide bond resistance, that the strain gradient under applied load varies depending on the rib spacing, and that the effective bonding zone against tensile load is the rib portion and the adjacent plain bar region.

Non-compression (NC) braced frames proposed by the authors have seismic response reduction capability due to elastic strain energy accumulation. This research aims to develop a response prediction method based on an equivalent linearization technique that takes into account the response reduction. In this report, a non-linear elastic hysteresis rule of multi-story NC braced frame is formulated and a method to create an equivalent SDOF system from the MDOF system applied the rule is described. From time history analysis results, representative seismic responses of 6DOF NC braced system and its equivalent SDOF system showed good correspondence.

This paper studied effective repair methods for H-shaped steel beam-column connections with fractured beam flanges under earthquake considering not only structural performance but also repair time and repair cost. First, a cyclic loading test was conducted to reveal the structural performance of the original and repaired specimens, which were taken out from an existing steel building constructed in the early 1970s. Next, the repair time and repair cost were compared among several repair methods, based on hearing survey to a steel fabricator.

There is room for further investigation regarding the effects of bonding area and clearance in buckling-restrained brace using steel mortar planks (BRBSM). In this study, experiments were conducted using BRBSM with varying bonding areas and clearances. The results indicate that by appropriately setting both the bonding area ratio and clearance, the lower limit of performance evaluation can be satisfied, and a compressive-tensile strength ratio comparable to that of BRBSM with full bonding achieved through clearance adjustment methods can be obtained. Furthermore, a clearance adjustment index for estimating the lower limit of cumulative plastic strain energy rate was presented.

This paper proposes the reinforcement method of existing vertical braces by applying the buckling restrained brace (BRB) utilizing carbon fiber reinforced plastic (CFRP) and urethane foam as buckling restraint materials. This proposed method allows buckling restraint materials to significantly reduce its weight and improve construction workability. In this study, the effectiveness of this method is confirmed through static incremental repeated loading tests and replication analysis using finite element method (FEM) on the designed specimens.

This study examines buckling-restrained braces using steel mortar planks (BRBSM) to clarify the influence of clearance between the core plate and restraining parts on buckling modes. Cyclic tests were conducted on specimens with partially pasted clearance-adjustment materials and different clearance ratios. Results showed that buckling mode numbers increased with the compressive yield strength ratio β, stabilized at β=1.0 for C8S and β=1.2 for C20S, and exceeded evaluation formulas, increasing with larger clearance.

With heating from the fire-proof test, the surface layer of wood carbonizes. Therefore, whether wooden fire-proof members extinguish or continue to combust depends on the combustion of the charcoal. Thermogravimetric analysis on Japanese cedar and Japanese larch was conducted and the differences in combustibility for two species were analyzed. A 90-minute fire-proof test with heating from two sides was conducted on a wooden fire-proof member utilizing the differences in combustibility. By utilizing the differences in combustibility, it is considered possible to produce wooden fire-proof members that extinguish combustion.

This paper presents a simplified method for predicting ground response under multiple-person rectangular excitation, relevant to large-scale events like concerts. The approach considers geometric distribution, timing offset, and jump landing effects, introducing correction factors for excitation force reduction. Validation using finite element analysis and normal mode solution shows agreement with simulations. The results demonstrate that the proposed method enables practical estimation of ground response, supporting rational design and safety assessment for event venues. This framework provides engineers with an efficient tool for evaluating vibration effects without complex modeling.

This study investigated the effect of balancing power supply and demand in the posi-watt thermal storage air conditioning system among different buildings and years. Air conditioning loads were estimated from the whole building power consumption data measured by smart meters. Adequate water capacities were determined as 3–7.5 tons for each condition. Energy simulation results indicated that the operational electricity price in the proposed system was 6.5–21% lower than that in a conventional air conditioning system. The effect of balancing the supply and demand was more significant when cold water was produced at lower prices.

This paper introduced a hybrid-source heat pump system combining air and ground heat sources in a detached house and evaluated its effectiveness. Key findings include: 1) In air-source mode, pump inactivity allowed rainwater and surrounding soil to be heated by ground heat. After nine days of operation, an eight-day recovery period raised tank water temperature by 5℃, enabling reuse; 2) In ground-source mode, outdoor unit inlet air temperature rose up to 9.7℃, averaging 4.3℃, and stayed 4- 10℃ at night; 3) Tank water dropped 8-13℃, and nearby soil 5-7℃.

The characteristics of electricity and heat demand in the Minato Mirai 21 district were estimated and analyzed. Electricity demand under normal and emergency conditions showed a nearly linear relationship. In contrast, heat demand exhibited significant seasonal variability during normal conditions but remained relatively stable during emergencies. Observations of temporal and spatial imbalances in occupant distribution underscored the necessity for effective evacuation guidance. Additionally, heat demand was higher during the daytime in both summer and winter, indicating peak energy requirements during these periods.

This report uses hourly electricity supply data for FY2030, when renewable energy is expected to expand. First, the characteristics of VRE and decarbonized electricity supply were analyzed for each electricity area. Based on this, the share of electricity consumption in standard non-residential buildings that can be met by VRE or decarbonized sources was calculated by region, building type, and time. Various analyses were conducted to assess the compatibility of supply and demand. By identifying differences and factors affecting compatibility, this study aims to provide insights into promoting the adoption of renewable energy.

This paper aims to report present condition of the “peripheral suburban residential area” in Osaka. These residential areas, which were developed about 40 years ago, are facing to deterioration of living environment by vast of vacant lots. We can find over 40% of housing plots are vacant, and about its 70% of lots are not in use and ruined. On the other hand, we were also able to find examples of effective uses, and 50% of un-used lot will be able to use as a new spatial resource.

In order to understand the current state of urban living, this study investigates detached houses not by examining their physical conditions, but by focusing on the life elements of the residents. The survey area was Hakusan 4-chome, Bunkyo-ku, Tokyo, a residential area with many small houses in the city center. The research method will be map creation and field surveys.

This study aims to assess the status of child psychological treatment facilities nationwide and provide key considerations for planning such facilities with a focus on comprehensive environmental therapy. Specifically, three tasks are set: 1) Understanding the layout characteristics of existing facilities, 2) Analyzing the practice of comprehensive environmental therapy and utilized spaces in facilities opened or relocated since 2015, and 3) Understanding the spaces used for comprehensive environmental therapy during the process from admission to discharge.

Since the modern era, bank buildings constructed by regional banks in Japan have served as familiar landmarks in key areas of city centers. In recent years, however, due to organizational restructuring and the spread of internet banking, many branches have been closed or consolidated, and these buildings are losing their original function. This paper investigates the status of such bank buildings for five regional banks in the Chugoku region. It identifies cases of conversion to other uses and reports their details, providing foundational data for exploring strategies to convert former bank buildings into valuable regional resources.

This study clarifies the trend of location changes of public facilities converted from commercial buildings and the spatial development in cases converted into public libraries. The findings are summarized in the following three points: Firstly, many public facilities relocated to commercial buildings prioritize accessibility from rail stations, resulting in a shift closer to station. Secondly, facilities located near stations have seen a greater increase in visitor numbers after relocation compared to those situated farther away. Thirdly, within libraries, original commercial spaces have been effectively utilized to create more spacious areas for visitors to stay.

This research investigated the effects of introducing monitoring support devices on night shift staff in facilities for persons with disabilities. Staff behavior and mental strain were observed before and after the devices’ introduction. Results showed that the effectiveness of monitoring devices in reducing physical and mental burdens on night staff depends on both resident disabilities and facility design. Notably, the facility with a higher proportion of intellectually disabled residents and fully private rooms experienced more positive impacts from the devices, demonstrating the importance of matching technology to specific care environments.

This study examined palliative care units (PCUs) opened in Japan during the COVID-19 pandemic (2020–2023). Forty facilities were identified, of which 33 were surveyed in detail. Most were renovated wards within existing hospitals, and the establishment pace was about half that before the pandemic. The proportion of private rooms remained stagnant, and regional disparities persisted. Statistical analysis showed that higher private-room ratios and larger floor areas per bed were associated with greater proportions of terminal care admissions. Findings highlight ongoing challenges in equitable PCU distribution and facility design to meet evolving end-of-life care needs.

This technical report examines the spatial configuration and usage of classroom units in Vienna’s Education Campuses, developed in response to contemporary educational reforms emphasizing individualized, group, and self-directed learning. Based on architectural drawings analysis and on-site observations of five campuses, the study clarifies the configuration, area composition, and functional relationships of key spaces, including “Bildungsraum” and “Multipurpose-spaces”. The findings reveal how unit-based planning, characterized by large shared spaces and flexible furniture arrangements, supports diverse learning activities and offers valuable insights for future school planning in Japan.

The division of disciplines in architectural design is expected to continue to progress, but there is insufficient research focusing on the integration of related expertise such as Structure, Architectural acoustic and Stage engineering. From this perspective, this paper reports on the refurbishment of Usagi Hall in Tsukiminosato, Fukuroi-city. Steel substructure was newly inserted into the ceiling to make it a seismic ceiling. The related design issues are 42 items with 8 fields of expertise. By describing and analyzing a diagram of the relationships between these items, this paper clarifies “Multidisciplinary Integrated Parts” that designed by multiple fields of expertise.

This paper aims to analyze an experiment project led by Seki City, Gifu Prefecture, in which a private parking lot was turned into a place managed by the city and architectural designers and joined by the citizens as short-term tenants. Since the citizens’ tenants were ruled to work within one week, they were changed frequently. In conclusion, the characteristics and values created by the frequent change of contents in the experiment project were clarified based on the analyses of the interrelationship between the nature of the social experiment, its management policy, architectural characteristics, and the frequent change of contents.

Creating environments suited to children’s physical and psychological development is crucial. This study aims to clarify children’s ideal images of housing and their characteristics. The method employed was a “collage” approach, in which children created ideal homes by cutting and pasting photographs, followed by interviews. The results revealed that many children envisioned spaces where they could interact with nature. In addition, they expressed admiration for features absent in current homes, and these preferences appeared influenced by gender and housing type. This method was suggested to be effective in eliciting preferences from children who find verbal expression difficult.

At present, artificial intelligence (AI) has demonstrated remarkable advances in multimodal AI. In this study, we employed a widely used, general-purpose AI without additional training to extract spatial information from multiple indoor photographs taken at the sites of fall accidents in residential environments. The AI was then tasked with analyzing the causes of the falls and suggesting countermeasures. The results indicated that spatial recognition itself was difficult in restrooms and bathrooms. However, in other rooms, the AI generally provided appropriate responses regarding spatial understanding, explanations of fall circumstances, and recommendations for improvements.

This study investigated a renovation project of a room in a maternal and child living support facility in Japan, where reused materials were actively implemented. Through involvement of the architect in sourcing, inspecting, and coordinating reclaimed components, the project illustrates how reuse practices reshaped the design process. By analyzing workflow changes and quantifying reuse rate and CO₂ reduction based on material mass and transportation data, the study revealed the additional workload and cost implications of reuse. It aimed to contribute to the development of institutional frameworks that supported the sustainable integration of reuse in architectural practice.

This study examines people who still live in thatched-roof houses as ordinary residences and annually harvest thatch from their own grasslands for maintenance. The research aimed to clarify practical methods of maintaining thatched houses in modern times. Results revealed that such practices are closely related to the local climate, the presence of experienced thatchers nearby is important, and that maintenance is integrated into everyday life. These findings suggest that such efforts represent a noteworthy new model for the sustainable maintenance of thatched houses today.

In this study, we clarified the construction costs and funding sources for the reconstruction of government buildings damaged in the Great East Japan Earthquake, investigated annual operating costs to calculate life cycle costs, and visualized the burden on residents over the lifespan of the buildings. As a result, we found that although 95.4% of the construction costs were borne by the national government, the national government’s share of the life cycle costs was only 23.3%, and that reconstruction funding could increase the long-term burden on residents.

This paper presents Oda Project, a community space built in a container settlement after the 2023 Türkiye–Syria earthquakes. Inspired by the initiative of Minna no Ie and KASEI’s participatory approach, the project employed a Japanese timber-frame system constructed by students, residents, and local carpenters. The study covers 15-month of preparation, mock-up, and construction, addressing challenges of material sourcing and design adaptations. Through comparative analysis, the findings emphasize the rapid and efficient structural system for unskilled labor, the value of mock-ups, and the need to support vulnerable groups, particularly children. The study offers a replicable framework for future recovery efforts.

This paper analyses the methods of spatial composition of classroom in seven large scale junior and senior high schools in Japan. Consideration was given through an analysis of subgroups, grade groups and places for students. The following four characteristic methods were extracted. 1) The use of subgroups in the formation of HR groups. 2) A large plan with an atrium for the formation of middle and high school cohesion. 3) Combination of atrium and places to link classroom groups and other groups. 4) Nested multiple scales of places to accommodate groups of different scales.

This study conducted a survey of the tea ceremony house “Koushouken” using 3DLS, and created 2DCAD drawings from the measurements. This digital data with detailed dimensions is an important resource for recording, preserving, and passing on the interior space of the tea ceremony house. Furthermore, the 2DCAD drawings were compared with the original drawings of Tenryu-ji’s Shinjoin tea ceremony house as “Honka” to determine if there were any differences between the two. As a result, although there were some differences in the dimensions of the double sliding doors, the tea ceremony room “Koushouken” could be evaluated as a “Utsushi”.

This report examines the operating conditions of three home service robots in relation to the height and width of steps. The results show that important performance factors differ when going up or down steps. When going up steps, speed is the main factor for a robot without step detection. The relationship between the wheels and the size of the step also has an effect. For robots with step detection, the gap between the base of the robot and the floor is important. A new finding is that increasing the height of the step triggers step detection for safe descent.

This study examined the relationship between stair tread width and the perception of vertical ascending distance using immersive virtual reality. Participants ascended stairs in a virtual environment under different tread conditions and adjusted a reference object to match perceived elevation. The results revealed that 1) narrower treads led to greater perceived ascent in short staircases (5 steps), and 2) as the number of steps increased, participants tended to underestimate ascent distance. These findings suggest that tread width and step count shape perceived ascent and can inform spatial design.

In this study, to gain insights into the appropriate use of urban elements, we observed the use of fixed tables and benches installed in the plaza in front of Building No. 7 at the Setagaya Campus of Tokyo City University. Based on the collected data, diagrams of human gathering patterns were created, and group size, occupied area, and occupancy rate were calculated. The results showed that the size and density of the gatherings varied depending on the number of people.

In Odaka, Fukushima Prefecture, which was affected by the nuclear accident, a facility for passing on the local history and experiences of the disaster was built by residents through the renovation of a kindergarten building that had not been demolished. This paper reports on the process leading up to its opening and the design of the exhibits and provides insight into the local heritage facility in the nuclear disaster area, which differs from a public facility.