In this report, the history of stipulations relating to grading of coarse aggregates was investigated. In the course of survey, great influence of ASTM standards on those in Japan was verified. So many changes were proposed in the stipulations of JASS 5 and related guidelines on the way, but finally those were made consistent with the specification of Japan Society of Civil Engineers, that is, ASTM C 33 except for the few sieve sizes. The stipulations of JIS for slag and recycled coarse aggregates were established or revised in a similar way with that of JIS for crushed stone.

A variety of coating materials are available as finishing materials that suppress carbonation, which is the main cause of degradation of reinforced concrete buildings in general. Therefore, accelerated carbonation tests, outdoor exposure tests, and carbon dioxide gas transmission rate tests were carried out in various water-based finishing materials, and the carbonation suppression effect was confirmed for the purpose of improving the durability of reinforced concrete buildings. The possibility of predicting the suppression effect of the coatings through a mathematical formula was also examined.

It is necessary to reduce greenhouse gases in the construction industry to reduce environmental loading. Therefore, we confirmed the performance of concrete using ground granulated blast-furnace slag, which is expected to reduce carbon dioxide emissions. As a result, the influence of the ground granulated blast-furnace slag usage rate on the strength development and durability could be confirmed. In addition, from the results of the accelerated carbonation test, the durability design strength could be set, and a similar value could be set A and B classes as that of normal concrete.

A concrete pumping-up experiment for full-scale CFT column using two different mix designs of strength lower than 45 N/mm² high-fluidity concrete with admixtures containing viscosity modifying agent was carried out to verify its applicability.

As results, it was verified that satisfactory filling property could be obtained even with admixtures containing viscosity modifying agent, coefficient of pumping-up resistance at the inlet was within the limits of CFT guideline, and strength correction value S_c considering variation of concrete strength near diaphragms was less than the recommended value in the CFT guideline.

We conducted a survey on the actual conditions of material temperatures at ready-mixed concrete plants in 4 areas (Fukuoka, Osaka, Aichi, Tokyo) in hot weather in 2018. Cement is 45-55℃, groundwater is 20-25℃, and other materials are slightly lower than 30℃. The amount of temperature increase of the material temperature with respect to the outside temperature of 1℃ is 0.38 to 0.4℃ for aggregate and 0.25 to 0.32℃ for mixed water other than groundwater. Based on the current situation of 4 areas, the need for further temperature control measures for the materials used was shown.

Consideration for environmental load using blast furnace slag in concrete, we conducted various experiments. As results, even if a large amount of blast furnace slag, satisfy the required performance of the fresh concrete and structures by conventional mix design. The required durability performance is ensured by wet curing for a period set from the average temperature during the curing period and the expression of compressive strength. Compared to concrete using ordinary Portland cement, carbon dioxide emissions at the same strength are reduced by 9 to 63%. This study is expected to increase the spread of environment-friendly concrete.

Panam Nagar is one of the most important areas in Bangladesh where old buildings are preserved. In this research, we measured the dimensions of the bricks and conducted elemental analysis of the samples in order to obtain basic information on the construction age and manufacturing method of the bricks, which will be useful for future conservation and restoration. As a result, the height dimensions of the bricks were divided into two major groups and there was no clear difference in the constituent elements of each group.

In this study, a flexural loading test of a wooden beam with CFRP rods embedded in grooves provided on the tensile surface of the beam was performed and experimental investigations were conducted regarding a flexural reinforcing effect of the CFRP rod.　As a result, it was shown that as for beams reinforced with CFRP rods, a large increase in flexural rigidity and ultimate flexural strength was experimentally confirmed in comparison with non-reinforcement, and a reasonable correspondence was seen between the calculated value of flexural rigidity by equivalent cross-sectional analysis and the measured value.

In this study, shake-table tests were conducted on a three-story RC structural frame with FIX windows and sliding windows as test specimens at E-Defense facility. Windows were set on 2nd and 3rd floor of the specimen. The inertia force and story-drift applied to the windows differed by floor. By comparing this difference with damage observation results in the experiments, the effects of inertia force and story-drift on the damage to windows discussed.

The Ministry of Construction Notification No. 1454 of 2000 stipulates the standard wind speed for calculating the wind load acting on a building. The standard wind speed is based on the 50-year return period wind speed, which is obtained by the stochastic method using the wind observation data. The present paper verifies the validity of the standard wind speed by comparing the 50-year return period wind speed obtained using the strong wind observation records up to 2019 with the standard wind speed.

The daily maximum temperature of steel materials installed outdoors was estimated using the daily maximum values of the outside air temperature and the amount of solar radiation. By making the following assumptions, it was possible to estimate with good accuracy with respect to the measured values. 1. The total heat transfer with the external environment is 0 (steady state). 2. Heat transfer to the external environment is performed through the polygonal outer surface that surrounds the member. 3. The temperature of each part of the member is uniform with the average temperature of the member.

Under stud-type shear panel damper using low-yield strength steel is installed in mid- and high-rise buildings, there is a problem derived from the excessive axial force by the variable axial force. In this paper, the effect of compressive axial force on the hysteresis characteristic of the damper is examined by experiment and FEM analysis. In consequence, the stable hysteresis was provided under compressive axial force ratio less than 0.3 with specific combination of flange and shear panel. Also, the influence of the hysteretic performance of the stud-type panel damper subjected to bi-directional horizontal loading and axial force is minor.

In the future, skyscrapers or large structures will become lighter and more flexible. In order to clarify the aerodynamic behavior of such structures by wind tunnel test, flexible, low-density square prism models were developed using polyurethane foam. In this report, mechanical properties and bending vibration characteristics of the models are investigated by material tests and vibration tests. The results show that the models can be treated as uniform and elastic within the range of the deformation occurred by the across-wind aerodynamic vibration. It is shown that, bending vibration characteristics can be evaluated using the Bernoulli-Euler beam theory.

Viscoelastic (VE) dampers as passive control device for high-rise buildings has recently gained research interest due to its effectiveness in dissipating both seismic and wind-induced vibrations. Evaluation of VE damper’s dynamic properties is considered to be computationally expensive due to its complex properties and consideration of heat conduction and transfer effects. A simplified method to predict dynamic properties of two-layered dampers has already been proposed but is limited only in steady state. This paper proposes an extension of that prediction method to the transient state considering the effects of heat conduction and transfer regardless of the number of damper layers.

In this paper, deformation modulus in an evaluation method of coefficient of subgrade reaction were evaluated. As a result, the variation of deformation modulus obtained from the pressuremeter tests can be suppressed its variation by considering the strain dependency of the ground rigidity. Furthermore, the relationships between the deformation modulus obtained from the pressuremeter test and the PS logging can be approximated proportionally, and the relationships between the deformation modulus and the SPT N-value are approximated by a power approximation formula with an intercept, which enable to unify evaluation of the deformation modulus.

This paper reports on full-scale construction tests of cast-in-place concrete belled piles using high strength concrete with large bottom area, and the following conclusion are drawn. 1) The proposed technique enables the excavation with an expanded bottom shape having a bottom area lager than the size of the used bucket. 2) A scraper-type tool can reliably treat slime to the periphery of the pile bottom. 3) The pile constructed by casting concrete met design dimensions and strength.

The combinatorial optimization of cross-sections of latticed shells can be solved in a small computational time by using sequential quadratic programming. However, in the case of steel structures, the obtained optimal solution cannot be used as it is because they are usually composed of standardized member cross-sections. In order to solve such a problem, post-processing method to convert the optimal cross-section obtained by sequential quadratic programming to a normalized member cross-section is proposed in this study. It is shown that the proposed method can solve the combinatorial optimization problem for lattice shells in a small computational time.

We have developed the K-type braced shear wall that has superior performance for application to middle or large scale wooden structures, and verified its seismic performance. For the brace, the buckling restrained brace was used to restraint buckling by sandwiching flat steel with wood. As a result, it was confirmed that the K-type braced shear wall has a high energy absorption effect due to its spindle-shaped hysteresis characteristic. It was also confirmed that the standard shear strength is 34.8 kN, which is equivalent to 17.8 times wall magnification.

The aim of this study is to establish the design method of the glulam bracing shear wall using drift-pined joint with inserted steel plate. In this paper, we conducted the cyclic loading test for the specimens with 3 drift-pined joints placed near each glulam edge to grasp the mechanical behaviors. From the test results, we found that the stiffness was overestimated while the strength was predicted precisely by the calculation and the plastic deformability of the joints was improved by the reinforcement of full-thread screws, the slit opening stops and the use of the drift-pins of higher strength.

This study proposes a rehabilitation method (emergency retrofitting) to restore the axial compression capacity and shear resistance mechanism of shear-damaged reinforced concrete (RC) columns. For the emergency retrofitting of shear-damaged RC columns, coupler and aramid fiber belts are used. The key concept of this approach is to provide active confinement to firmly confine damaged RC columns externally. The active confinement is used to close cracks in damaged RC columns and to recover their vertical and lateral load-carrying capacities and ductility. To investigate the rehabilitation capacity using fiber-belt prestressing, axial compression and cyclic loading tests were conducted in this study.

This report shows the structural retrofitting of a two-story reinforced-concrete (RC) welfare-facility building in Niigata prefecture, which was built in 2002. During the Chuetsu earthquake in 2004, the first floor window under the bathroom was damaged. Our investigation revealed that the damage was caused by an error in the structural design and insufficient girder strengths. Thus, such RC girders were retrofitted using the beam string structures composing steel members. The stress was reduced by introducing a pushing force to satisfy the allowable stress. This method was simple, easy to install, and economical.

MEMS acceleration sensors were attached to columns, beams, a wall of a full-scale RC frame specimen subjected to static cyclic lateral loads. Rotation angles of the sensors relative to the gravitational acceleration direction were measured. The changes of the measured angles were used to calculate the story drift of the frame specimen, assuming deflection curves. The results showed that, the story drift measured by the sensors agreed with that measured by conventional methods; adopting this system to vertical members was more effective than to horizontal members; the accuracy of the measurement was influenced by shear cracks and yielding of reinforcement.

In the 2016 KUMAMOTO earthquake, the R/C soft-first story building designed after 1981 was severely damaged. To mitigate the damage, study on seismic retrofit with UFC panels has been conducted. Investigation to evaluate structural performance of the retrofitted building with soft-first story is necessary. This paper presents an analytical model for the retrofitted R/C soft-first story frame specimen with UFC panels. The modeling method for such as column retrofitted with UFC panel are discussed, especially it’s focused on structural performance of this retrofitted specimen dependents on mortar in joint between UFC panel and concrete stubs.

Recently, after a huge earthquake, reinforced concrete buildings were not available or demolished due to sever damages. Therefore, a damage assessment becomes important; hence, measuring damages from images is one of the most useful techniques. In this study, crack widths of the non-structural wall specimens were measured by using plural deep learning model. By the models which provide the extremely small values of Accuracy and Precision, cracks could not be predicted. While, the deep learning model, in which the values for Recall and F1Score were high, could properly identify the cracks; then, the crack width was reasonably measured.

Further shake table tests were conducted to examine the seismic performance of unit houses (prefabricated metal houses). A specimen comprising 4 unit-house units connected vertically and horizontally was subjected repeatedly in the long-side direction to the JMA Kobe record. The nonstructural, external wall panels increased the strength of the specimen twofold. The energy dissipated by repeated slipping of the slip-critical bolted connections equaled 88% of the total energy dissipated by the structural frame.

This report describes the overseas field survey observing the ambient vibration characteristics of historical construction-style masonry buildings in Nepal. Most of these buildings are categorized as ‘non-engineered’ constructions without the proper structural design and adequate material production management. Micro-tremor measurement was conducted at the 13 historical masonry buildings in Nepal. The first natural frequencies of these buildings were evaluated and these values were compared with the ‘screening model analysis’ results. Moreover, vibration characteristics of every floor of selected 4 buildings and the influence of the out-of-plane vibrations of the masonry walls were also observed.

In this study, a stiffening method to improve the buckling resistance of steel plates under compressive loading was investigated using an unbonded FRP, which is an effective method against buckling and unstable phenomenon in structures. The buckling behaviors of the steel plates were analyzed by experiments and mechanical modeling. As the results, it was made clear that the compressive strengths of the steel plates with unbonded FRP stiffener can be evaluated by the design method. Moreover, it was shown that the post-buckling load-deflection behavior can be reasonably estimated by the proposed mechanical model.

In recent years, severe flood damage has continued in Japan, with 80% of the damage coming from inundation depths of one meter or less (Level-1). Typical recovery costs are over 6 million yen for house repair, and another 3-4 million for home contents. To prevent Level-1 flood damage, we propose a flood-proofing house with measures against inundation, backflow of drainage pipes, submersion of equipment, and buoyancy. The effectiveness of these measures are demonstrated with a full-scale flood test. Some of the inundation and backflow measures can be applied to existing houses, resulting in the reduction and delay of damage.

We propose a floatable flood-resistant house that is resistant to flooding up to a depth of 5 m. It includes foundation, water supply and drainage pipes that enable smooth ascent, and mooring devices that prevent the loss of the house and slippage during landing. We also propose a draft calculation method to check the ascent balance. These measures and calculation methods were demonstrated in the inundation test of the full-scale test building. It was shown that it is possible to remove foreign drifting objects under the house after landing and to pull it back to its original position.

An increasing number of schools are being rebuilt owing to problems such as decrepitude and weak seismic capacity. During the reconstruction process, temporary school buildings are often erected using a prefabricated structure. Such temporary school buildings lack acoustical performance and are exposed to construction noise. This study investigates the actual condition of these buildings, using the case of a temporary school building of an elementary school in Tokyo, and examines the possibility of improvement and countermeasures that could be taken in the operational scene.

When predicting environmental vibration, it is necessary to properly evaluate the distance damping of the ground. However, there is a lack of examples of measurement of transfer function using a vibration source with known excitation force. In this study, we conducted shaking experiments at three sites with different ground conditions to measure the accelerances. Since it is important to know the shear wave velocity to predict the ground vibration, the difference of the several regression equations from N-value was clarified by the reproduction analysis.

In “Introduction to Environmental Vibration Design for Ensuring Habitability” published in June 2020, the example of performance matrix for road traffic vibration in different period is showed. However, there are few cases of making a vibration measurement in a real house for one week. In this report, we made three patterns of vibration measurement for road traffic vibration, and then we examined variation in vibration level for one week. As a result, vibration level depended on changes with the passage of time. Additionally, it was suggested that paying attention to the measurement position when measuring vibration is necessary.

A magnetically shielded room (MSR) equipped with an automatic door is designed and developed to improve a convenience of door operation. The MSR is designed for biomagnetic measurements (e.g., magneto-encephalography), and it is required that such MSR has high shielding performance because biomagnetism is extremely smaller than environmental magnetic noises. In particular, we devise the laminar structure of shield plates and the automatic door structure to prevent leakage magnetic noise passed through a gap. Furthermore, the shielding performance is evaluated by an actual magnetoencephalography measurement, and we confirm the developed MSR has shielding performance which enables to measure biomagnetism.

A simple and practical earth tube system that does not require to be buried deep underground was developed. To investigate the effect of geothermal heat utilization in the central air-conditioning of the house, field measurement and numerical simulation in the model house equipped with the earth tube and thermal storage mat foundation were conducted. In this paper, measurement results for the effects of the earth tube and temperature distribution of the mat foundation over two years were analyzed. Additionally, the reduction effect of the heat load by the adoption of the earth tube and thermal storage mat foundation were clarified.

This paper describes results of a field measurement in which the feasibility of low temperature heating and heating performance improvement by means of convection enhancement around radiators were examined in radiant heating with plastic multi-tubular radiators in an existing reinforced concrete house without thermal insulation. Radiant heating with plastic multi-tubular radiators can make both room air temperatures and MRTs 22〜25℃ and PMVs 0 〜± 0.5 with supply temperature being 30〜36℃. Convection enhancement around radiators by means of small DC fans increases their thermal emissions in 140W/m² at most.

In recent years, passive designs, that acquire solar radiation from large windows during winter time, are becoming widespread. However, due to privacy issues, there are some houses in which curtains and other shading devices remain closed throughout the year. In this research, we focused on the roller blinds that can control the solar radiation and view, in response to the weather conditions and the surrounding environment, and measure the solar heat gain and the heat transfer by component of the windows with roller blinds under the actual environment.

This paper describes the thermal environment in “A House in Sapporo (1968)”, by architect Tetsu Katono. In winter, air temperature versus MRT of the living room were 19℃ versus 21℃ (outdoor: -0.9℃). Based on the value of warm radiant exergy from the wall, cognitive temperature was estimated 20℃, and it was presumed that the room felt “warm”. In summer, air temperature versus MRT of the living room were 26℃ versus 28℃ (outdoor: 30℃). Cold radiant exergy to bring coolness was emitted from the wall surfaces and cognitive temperature was estimated 25℃.

Airflow-pressure loss characteristics of duct fittings for air-conditioning and ventilation systems are required when HVAC designers determine total pressure loss and select fans of appropriate capacities. More accurate characteristics contribute to reducing costs for initial installation and operation as well as to higher energy efficiency of the HVAC systems. This report verifies the accuracy of simplified test methods using a short duct attached to the tested air terminals, and compares results by the simplified method with the results by the precise method, which has already established.

This study is a continuous study to clarify the actual situation of performance improvement Inspection in the market, and the following was found. 1) Even for businesses belonging to one organization, the position of inspection is completely different between design offices and construction companies. 2) As for Inspection items are 3 to 6 items, and there was a difference depending on Inspectors, not a difference in design offices and construction companies.

This paper examines the process of introducing the residential environment check and improvement program in Edamitsu-niku. In this district, which did not have a basic community event, the program gradually expanded the subject of checking from vacant houses and land to become established. The participation of the commissioned welfare volunteers in this process was a unique development. This indicates that the commissioned welfare volunteers can function as information hubs in the living environment management of the area they are responsible for.

The purpose of the study is to identify the needs for the first-time meeting style with staff when considering the purchase of a new detached house. The research conducted a web questionnaire survey of 1,000 people. As a result, we found that the client wants a meeting style that can use photographs while maintaining a certain feeling of distance from the staff. On the other hand, we found a result that clients shun the meeting style held in person with the staff at the housing exhibition place. In addition, the effect of COVID-19 on this study was small.

Investigating students’ behavior in subject center system school, this report aims to understand how students select places to stay in relation to other students' groups and teachers. The analysis shows that, while the majority of students stay in their homebase or the classroom for the next class with a group of two to six students between classes, several characteristic behavior that some students select their spaces and routes that can distance from the majority student groups. Those are a part of the system of using the school space in response to the fluid relationship between students and spaces.

Local public facilities should be consolidated based on the inhabitant’s usage and living areas. This study clarified the actual usage tendencies of those facilities in a widely merged municipality in Japan by a questionnaire survey. We found that the user’s age were depending on types of facilities. And people in mountainous areas go out much far away for daily shoppings and medical services. Their living areas were wide alongside valley, the choice of facilities follows on their accessibility. They preferto go to a far away but larger facility rather than a smaller facility in their neighborhood.

Continuing from the results of our previous report based on simulating the construction of a medical aid station, here we clarify the operational requirements to enable the smooth operations of such facilities. The results clarified the following: (1) Information spaces must be installed at multiple locations; (2) Imaging devices should be installed in a central location to ensure easy access. In addition, they may be installed near critical areas that are frequently used; and (3) The overall layout should allow division of the space into multiple areas based on the severity of casualties.

Toyama-style day care centers were affected by the temporary closure of schools and other facilities under the COVID-19 pandemic. In this study, their management situations and infection preventions were investigated through a questionnaire survey. The results are as follows. The impact of COVID-19 on management is significant. Some facilities installed the wrong infection prevention while the majority followed the MHLW’s guidelines. Small-scale facilities continued to provide services by reducing contents and confirming users’ safety by phone. We saw the emergence of new BCP through the Toyama-style, where users change each other's facilities and both staff are strongly connected.

Cooperative-style group homes, where the elderly with dementia and persons with disabilities live together in one integrated space and structure, follow the current laws and guidelines. Cooperative-style group homes are expected to provide collaborative care for cohabiting elderly with dementia and persons with disability in their local area. The aim of this paper is to contribute to the body of knowledge about of Cooperative-style group homes, especially the current status and challenges of architectural and management aspects.

This research aims to clarify for appropriate long-term use in the planning and operation of public cultural halls in the future by clarifying issues and requests for public cultural halls from the perspective of stage technology companies who are familiar with stage equipment. The purpose is to provide guidance for stage technical planning. The requirements for each company’s stage technology planning were shown in 222 items in four stages: planning / design, construction, daily life, and repair / equipment renewal. From this research, we were able to obtain useful knowledge about the stage technology planning.

In recent years, learning commons spaces have become prevalent in university libraries throughout Japan. The purpose of this study is to clarify the characteristics and operational status of learning commons by focusing on spaces where students can eat and drink, which are thought to contribute to their active learning. The study targets 125 university libraries across Japan, and clarified that students use the spaces in different ways depending on their spatial characteristics, as well as operational issues. It suggests the possibilities and challenges of effective use for active learning.

The study analyzed the changes of open plan classrooms improvement for more than 30 years until 2013 in all municipalities of Tokyo. The main findings are as follows. 1) The number of “open type” partitions in open classrooms has decreased rapidly in recent years. 2) On the other hand, “sliding door type” has become the mainstream. 3) The area of multipurpose space adjoining to the classrooms is shrinking.

The purpose of this study is to clarify the characteristics and utilization of the plan of temporary child protection centers, and to grasp the evaluation by users. In the analysis, the characteristics of the floor planning and the trend of the area composition in the facilities in the local area were grasped. Through the evaluation of the living environment, it was clarified that the bedroom serves as a base for children to calm down and to have private conversation with staff. On the other hand, children are forced to spend time in limited space and daily routine.