In this study, durability of polymer-modified mortar is examined. The examination results are marshalled data about the relation with a polymer cement ratio and each property. In addition, carbonation resistance of polymer-modified mortar is evaluated. In the result, it is confirmed that compressive strength and air content have a profound effect on durability of polymer-modified mortar than polymer cement ratio. Moreover, it is confirmed that most all of commercially available polymer-modified mortar used in this study have necessary resistance for carbonation.
Organic reconstituted stone is often used as flooring of buildings in countries outside of Japan. As organic reconstituted stone contains polymer resin, it may discolor yellow by ultra-violet light and heat. At some construction sites, organic reconstituted stone became yellow. Authors conducted tests to investigate the causes of yellowing, methods of prevention and possibilities of further yellowing by replicating the process and making chemical analysis. They found out that long-term exposure to water and heat changes its chemical component and leads to the formation of chromophore having a conjugated double bond and auxochrome having a hydroxyl radical.
Various studies have been conducted to estimate the suppressive effects of coating materials on the carbonation of concrete. For many coating materials, a simpler and faster evaluation method than the accelerated carbonation test and the air permeability test is necessary. We applied a box method to evaluate the carbon dioxide permeability of coating materials and determined that the permeability could be evaluated quantitatively. In addition, the evaluation was completed within one or two weeks. Hence, the box method can evaluate carbon dioxide permeability rapidly and is useful for predicting the suppressive effect of coating materials on the carbonation of concrete.
In order to reduce the energy consumption of buildings and improve the resistance of aluminum framing members to condensation, the glass curtain walls with thermal break framing system are very important. However this framing system has barely been utilized in Japanese buildings. In this paper, we proposed the idea that glass curtain walls with both fins shading solar radiation and a thermal break framing system are suitable for buildings in the warm regions of Japan. Calculating results for the heat load confirmed that this idea has obvious benefits of improving the thermal performance and reducing the energy consumption.
The authors have developed an air-purifying interior finish applied photocatalyst to create a good and comfortable indoor air quality. Developed interior finish applied photocatalyst is a high-function calcium silicate board that has many microsized pores. The optimum amount of photocatalytic TiO2 is applied to effectively eliminate harmful gas by adsorption and photodecomposition. It is shown that developed interior finish eliminates harmful chemical gas and bad smelling gas. In addition, developed interior finish is used in the conference room at OBAYASHI corporation and it has been confirmed that it eliminates formaldehyde and toluene gas.
This paper presents a new performance-based seismic design method using PML(Probable Maximum Loss) for steel buildings. Monte Carlo simulation using three dimensional elasto-plastic dynamic analyses with two-directional inputs evaluate restoration costs of the building frame per component, and non-structural elements per place. This enables us to analyse the restoration costs and to improve the design to hit the target performance. PML of an example building was evaluated repeatedly and the detailed restoration costs information derived from this method helped to improve the design of the building by adding and rearranging vibration control braces to hit the target PML.
This report describes engineering bedrock motions in Urayasu and Yumenoshima sites using the strong ground motions recorded in the downhole array observations during the 2011 off the Pacific Coast of Tohoku earthquake. Site amplification characteristics of long period ground motions are discussed in Tokyo bay area, where soft surface layers on the engineering bedrock attributed to amplification of the ground motions with period range over 1s.
After the 1995 Kobe earthquake, the application of base isolation in detached houses increased in Japan. To date, about 4,000 base-isolated detached houses have been built. However, large base displacement of a base-isolated detached house, beyond the usual design limit, was observed in Sendai when the Great East Japan Earthquake occurred on 11 March 2011. In this paper, a new device is proposed for controlling seismic displacement of a base-isolated building structure by means of a friction damper with coupling mechanism. Experimental and analytical results show the effectiveness of the proposed device.
We propose a method to estimate the response of a seismic isolation layer using an accelerometer which is located immediately above base-isolated layer. The method is based on the assumption that seismic isolation structure is excited mainly by its first mode. In this paper, we estimate the displacement response of the isolation layer utilizing a state space expression and a transfer function between response acceleration and a relative displacement. Simulation and experiments results confirmed the feasibility of the proposed method.
The authors have conducted full-scale dynamic tests of the largest force-restricted tuned viscous mass damper (FRTVMD), and analyses of a single-degree-of-freedom structure incorporated with the FRTVMD. A comparison verified the validity of the linearization method for a non-linear viscous element in the FRTVMD.
Observation of indoor simuration during earthquakes was performed in the E-defense shaking table experiment by use of newly developed monitoring system with 360 degree video camera and ecceleration sensors. Response simulation of furniture in the room was tried using the software with realistic experessions. Parameters setting in the simulation such as the center of gravity, mass and friction coefficient are examined as compared with the experimental results. Introduced observation and simulation methods will be useful for educational purpose as well as disaster emergency response.
The ultimate bearing capacity formula of embedded foundation is specified in the guideline published by the Architectural Institute of Japan for design of building foundation. The rigid plastic finite element method was developed by Tamura and Ohtsuka to estimate the ultimate bearing capacity of footing. The characteristic of this method is to employ few strength parameters. It does not use the Poisson’s ratio and the elastic modulus since it directly deals with the limit state by disregarding the elastic deformation of building and ground. The strength parameters as cohesion, c and internal friction angle, φ are only employed. By performing a series of rigid plastic finite element analyses, the comparison of ultimate bearing capacity of embedded foundation was conducted between the formula of the Architectural Institute of Japan and the simulation results. On the dispersion failure mode of ground, the bearing capacity of penetration foundation was made clear by the width and the penetration length of foundation and the strength ratio of first and second layers of two layered ground.
The ultimate bearing capacity formulas of foundation and penetration foundation have been specified in the guideline published by Architectural Institute of Japan for design of building foundation. The rigid plastic finite element method was developed by Tamura and Ohtsuka and has been applied to estimate the ultimate bearing capacity of footing. The characteristic of this method is to employ limited soil constants in comparison with deformation analysis. It only uses the strength parameters as cohesion, c and friction angle, φ since it deals with the limit state directly by disregarding the deformation of building and ground. Through a series of rigid plastic finite element analyses, the comparison of ultimate bearing capacities of penetration foundation between the simulation results and the formula of Architectural Institute of Japan was conducted for two layered soil system of clay. The change in failure mode of ground was discussed with the geometrical ratio between the width of footing and the height of surface layer. The strength ratio of the surface and the second layers of ground was clearly shown to affect the formation of failure mode. The applicability of rigid plastic FEM was demonstrated to the assessment of ultimate bearing capacity of two layered clayey soil system.
In order to investigate the structural performance of glulam beams with holes, full-scale bending tests and FEM analyses were carried out. Two 9m long glulam beams with 9 round holes were used. The parameter of the tests was hole placement, the deviation of hole center was 1/7.2 of beam height. As a result, shear failure occurred in both beams, and the effect of the deviation on strength was considered to be small. Comparing between tests results and FEM results, we found that we could grasp the situation of tests using FEM results. But that’s the problem that the assessment of shear collapse is not established.
Earthquake-proof measurement, control regulation and automation at the existence wooden architectures are urgent problems. This time we obtain an opportunity to perform the seismic diagnosis and the seismic strengthening design of the wooden kindergarten building. We inspected earthquake resistance using the way of finding a pillar joint reduction coefficient by calculating backward N value calculation method in this seismic diagnosis. We also propose an earthquake-proof diagnostic procedure for wooden architectures which were reinforced with the steel frame members.
In this paper, we conducted tensile loading tests, with grid-bolted connections loaded perpendicular to the grain. From these tests, we would appear the relationship with the visual fracture characteristic, load-disp-behaviors and ductile factor coded in 2006 of Japanese design methods. As a result, the fracture characteristic is almost in brittle and we could see linear behavior in a diagram. We could show fracture information of the bolted connections graded on JC.
In this paper, tensile behavior of split wedge joint is examined. Tensile tests for split wedge joint are conducted. Fifty-four specimens are tested, and their parameters are dimension of post, beam, tenon, notch line and wedge and tree species of members. The tensile properties are shown from the experimental results. In addition, evaluation rule for tensile behavior of split wedge joint considering initial bearing stress by wedge is proposed. It is based on the result of embedment test of wooden materials.
The Yuasa-cho in Wakayama prefecture, which will be one of the most heavily damaged area in the next Nankai earthquake, is selected to consider how to reduce the earthquake damage of traditional wooden houses in the important district of groups of historic buildings. Seismic performance of 10 houses is evaluated based on microtremor measurements and structural characteristics investigation. As results, yield base shear coefficient of large houses with large hanging walls is about 0.2 and such houses may collapse at the maximum shear deformation angle of 1/25.
Recently, ultimate strength of r/c interior beam-column joints with floor level difference using mechanical anchorages has been researched. However, design method of such joints is not necessarily clear. This paper shows its design criteria and mechanism based on past tests result. Consequently, estimation method of design ultimate strength of such joints is clarified.
Loading tests were conducted using column-beam joint specimens with such a shear-bending capacity ratio in the panel zone as specified for practical design. 1) The Q-R curve indicated stable and ductile hysteresis with no rapid strength reduction beyond the maximum strength. 2) No difference was found in Q-R curve envelope between PCa and RC specimens. 3) The maximum strength at the column-beam joint where flexural yielding of the beam preceded could be accurately evaluated by ACI equation for beams. 4) No difference was found between PCa and RC specimens in the relation between equivalent viscous damping factor and inter-story displacement.
The author has proposed the formulas for estimating the confining ductility of R/C square columns. However, these formulas are not applicable to rectangular columns. In this paper, estimation method of the confining ductility of such columns is clarified on the basis of past tests result of wall specimens subjected to compressive force. Also, the required transverse reinforcement for ensuring the adequate ductility is shown.
An experimental database of 189 R/C bearing wall specimens with rectangular and barbell cross-section was made. The relationship between member classification determined by current standard and deformation capacity observed in experiment was discussed. Criteria of member classification were validated and some issues on the criteria were clarified. The accuracy of ultimate flexural and shear capacity estimation methods commonly used in member classification was also discussed.
An experimental technique using short beam-exterior column joint specimens was proposed to overcome a size limitation of the experimental equipment. Realistic moment distributions were simulated by applying additional moments to the ends of short beams. As a result of the verification test with a steel specimen, it was confirmed that curvature and axial strain distributions were consistent with theoretical estimations. Application tests of the proposed experimental system were conducted using two 3/4 scale R/C beam-column joint specimens representing an earthquake-damaged joint in developing countries. Seismic behavior of the joints was observed and represented by an asymmetric rocking model.
A small waiting room, shop, etc. have been installed on the elevated bridge, for railway customer. However, the design method of a small structure on the elevated bridge is not clear. In this paper, we estimate of seismic design force of the small structure on the elevated bridge, based on the response analysis and SRSS. And, we propose modified Ai based on the results of previous research and the results of the study were to 1/3 the weight ratio used in Ai. By using modified Ai, the seismic load is estimated at safe side. And, We estimated the value of the expression and the proposed shear coefficient (C0 = 0.5). As a result, the shear coefficient (C0 = 0.5) is actually to design, it can be easily computed on the safe side.
This paper presents deformation concentration phenomena in lower part of frames. Steel high-rise buildings subject to extreme earthquake ground motions collapse at only lower part of frame by plastification of columns in middle story of frame. The effect of column overdesign factor to deformation concentration region is verified. Furthermore the effect of skeleton curve of members and input ground motions are also investigated. In the case of small column over design factor and the plastification occurred in columns, the collapse is observed in further lower part of a frame compared with the case of strong columns.
We have developed a noncontact-type relative displacement sensor for structural health monitoring which is capable of measuring relative displacement and rotation angle of the object independently. The sensor is composed of a laser as a measurement target and two position sensitive detectors (PSDs). The accuracy of the sensor system was experimentally evaluated to be 0.10 mm in the relative displacement measurement and 0.22 mrad in the rotation angle measurement respectively. These results indicate that the developed sensor system has a sufficient accuracy for structural health monitoring.
Structural design of buildings is facing two major problems. The first is the negative attitude to the environment. The other is that there is no system can be evaluated easily damaged condition of the entire building, and economy. These problems are turning point. This is because it produces a structural design with a comprehensive perspective. It is necessary for general technology knowledge and it is not limited to the technical fields have been developed until now. I propose new structural design index and evaluation method to a solution for current problems and future prospects.
In Japan, many seismic retrofits are developed as a construction method which increases the safety of buildings in case of an earthquake. In recent years, seismic retrofits have been attracting attention as a construction method which raises the safety of buildings in case of an earthquake in South Korea. In addition, in order to spread seismic retrofits in buildings, it is important that they are able to be easily constructed. Therefore, this paper, suggests a metal connector that can be easily constructed in buildings and as a result of testing, it was clarified that the proposed metal connector can be applied to seismic retrofits.
In the field of building construction, mass consumption of wood materials contributes to reforestation and becomes the environmental burden reduction. However, an application to conventional timber structures only such as house has a quantitative limit. A newly developed timber structure that is able to make a large-scale building is expected. The authors are considering a composite steel-timber structure. In this study, bending test of the composite steel-timber beam members is conducted to grasp basic structural performance. Mechanical properties of the members are confirmed by the difference in joint method and width thickness ratio.
In the fire safety design for hospitals, operating suite, ICUs and CCUs are normally protected from fire in adjacent areas by fire separation walls, yet achievement of smoke separation is questionable. This paper discusses feasibility of smoke separation in fire of operating suite, ICU and CCU from other hospital parts utilizing the positive pressure air-conditioning system routinely used for cleaning level control in these areas. The study reveals capability of the normal positive pressure air-conditioning to prevent penetration of smoke from adjacent fires.
Fire resistance tests were conducted on loaded beam and post-beam joints of heavy hardwood (ZELKOVA) designed for traditional temple buildings. The tests revealed the followings: (1) predictability of the structural fire resistance of ZELKOVA beam with safety margin by the assessment of the bending buckling. (2) applicability of the traditional beam and post-beam joint designs to the Quasi-fireproof construction.
In order to evaluate effects of soil structure interaction on characteristics of traffic vibration propagation to buildings with different foundation type, vibration test was conducted to existing buildings with spread foundation and pile foundation from outside. Based on the results, simple evaluation technique for response of building foundation by ground surface point excitation using thin layer method supposing that traffic vibration derives from surface point excitation. It was shown that effect of soil structure interaction of pile foundation is more predominant than that of spread foundation at low frequency range.
In central Singapore there is a conservatory complex which comprises two cooled conservatories - the Flower Dome and the Cloud Forest, situated along the edge of Marina Reservoir. The Flower Dome replicates cool dry conditions while the Cloud Forest replicates the cool moist conditions found in tropical mountain regions. These domes utilize an externally fixed deployable fabric shading systems which are fixed between the main arch structures. This paper shows the algorithm of controlling the shading systems.
In this study, we compared the analytical values of light transmittance through venetian blinds calculated using the lighting simulation program Radiance with measured values of the transmittance. First, we measured the transmittance using a box with blinds on a building roof in summer and winter, and then, we simulated this box using Radiance under the same conditions. We investigated the appropriate conditions for simulation, including the number of planes in the curved surface of the blind slats and the slat reflectance for specular and diffuse reflections. Overall, the analytical values of transmittance are 0-10% lower than values measured.
Survey was conducted various water-saving equipment to set up a detached house of six. In a previous paper, I had reported the findings of wastewater concentration and water. In this paper, we further investigated the water use survey and the number of uses of the toilet. Survey were compared, including the results was carried out and this time the basic unit of 1970s. To organize the contents compared to the findings of the literature, such as an increase or decrease the amount of water for each use of the home.
Sale of hybrid gas-electric water heater was started in April, 2010. In this paper, the field survey was performed in the dwelling house which hybrid gas-electric water heater was installed. COP of hybrid gas-electric water heater on actual usage is 1.10 - 1.45. Compared with conventional water heater, hybrid gas-electric water heater can be expected to reduce 30% of hot water energy consumption.
A time-series assessment of urban environment was carried out by using “CASBEE-City” tool in Kobe city to visualize the disaster recovery process. As a result of the assessment, it was revealed that the score for quality of Kobe city calculated by the tool got drastically worse soon after the Great Hanshin-Awaji Earthquake in 1995. However, the score for quality of Kobe city has gradually recovered after the earthquake and has improved to the current position along with the progress of the reconstruction.
In this study, we aimed to confirm whether it is possible to improve the accuracy of the estimation equations of energy consumption rate of office buildings. By the difference in the type of heat source equipment, we classified the DECC survey data of 2009 fiscal year into three categories: “the electrical type”, “the fuel-based type with boiler” and “the fuel-based type without boiler”. As a result, using the multiple regression analysis, we were able to obtain more accurate estimation equations than before except for summer fluctuation-load rate in the electrical type.
Environmental performance assessment tool for municipalities (CASBEE-City) has been developed and upgraded since 2008. The tool automatically queries the database and extracts the necessary data for conducting the nationwide municipality assessment. The tool also incorporates GIS functionality and enables tool users to understand the conditions, strengths, and weaknesses of their municipalities in comparison with other municipalities in Japan by visualizing the assessment results on easy-to-understand maps.
CASBEE (Comprehensive Assessment System for Building Environmental Efficiency), developed by the Japan Sustainable Building Consortium, is now being widely used in 24 local government in Japan, since it was first introduced in to the green building policy of Nagoya city in 2004. To learn the current status of CASBEE by local governments, this report investigates the evaluation results of local versions of CASBEE in Nagoya city, Osaka city, Yokohama city, and Kyoto prefecture. From various statistical analyses and comparison, characteristics of evaluation results of the 4 local versions of CASBEE have been shown.
The reduction of residential energy consumption is a very important issue. Housing plans with a combined living room and kitchen are becoming more common. It is impossible to disregard the influence of the heat of cooking on the indoor thermal environment and on the total cooling and heating load in the home. We conducted online questionnaire surveys to find out the actual conditions of cooking behavior and energy consumption. The results identified the main factors that influence cooking energy consumption and showed that differences in energy consumption varied depending on household characteristics.
This research aimed at acquiring knowledge about the formation circumstances for the remodeling example which won a prize in “the housing renovation competition”. In the application works of the “competition”, in 13 years, the building age was extended from 22 years in 35, and the total construction amount is extended from 10 million yen to 15 million yen. In winning-a-prize works, there are remodeling which reproduces the vacant possession residence, remodeling which inherits a purchase residence as cultural assets, etc. These are outstanding examples of long-life housing.
This article is a study about Wooden Temporary Housing built for the victim who suffered serious damage in Fukushima by Tohoku Earthquake disaster and the later nuclear plant accident. As study content, we analyzed site, floor, section planning of Wooden Temporary Housing with a few past precedents and compared it with prefabricated one, and arranged it about physical characteristics. At the same time, we inspected about actual situation from construction to the present and future versatility and reuse after finished the use as temporary housing and aimed at it becoming an effective document for the future disaster.
In recent years, a major city Shanghai has been facing a rapid aging of population. In the meantime, since living at home is becoming mainstream for the elderly, there is an urgent need to provide an equipment and space with various measures that respond to the elderly in each residential housing. Therefore, we conducted a questionnaire survey and measured survey of elderly people living in public subsidized housing. In order to continue living at home, the elderly classified into four clusters consisted of personal conditions, family conditions, and living conditions. Through the analysis, elderly people’s needs for living continuation are found out in accordance with their conditions.
The aim of the study is to point out essential and critical factors to be considered at the stage of planning and design of hospitals in the case of suffering from great disasters such as earthquakes, because increasing possibilities are anticipated in hospitals accepting a number of casualties suffered from great disasters which will simultaneously happened in a region. In order to attain the aim, extensive literature and hearing/observation surveys were carried out targeting to the hospitals attached by Great East Japan Earthquake on March 2011. As the result, several items were pointed out.
This study aimed to elucidate the proper arrangement of various daily living facilities for the aged, and the following findings were made. Because of the high level of usage of such facilities by the aged, the following four types of facilities, in order of priority, must be maintained: public administration facilities, leisure-welfare facilities, leisure-resting facilities, and welfare facilities. It is necessary to plan pedestrian walkways because the frequency of walking among the aged is higher than that among the non-aged. And, it is essential to select appropriate locations for each facility, all which should be arranged within about a 400-m radius from residential areas.
This paper proposes a methodology for quantitative evaluation of three-dimensional visibility of green spaces by measuring the ratio of visible green in the omnidirectional field of vision. A method of measurement using CG models based on the solid angle was developed, and it was taken into consideration type of green space (high tree, low tree, ground cover plant) and shape classification of tree crown. The three-dimensional visibility of green spaces was then evaluated at Ritsumeikan University. In addition, the multiple planting design was simulated from the perspective of efficiently taking visibility of green.
This thesis estimates the rate between real acrophobic stress level and acrophobic stress level with immersive virtual system based on electro-dermal activity. One result is that the stress under the VR system is larger than the real stress. The other result comes from gender difference under the VR circumstance. The stresses of female participants are larger than that of male examinees. The reasons of these results can be due to the system. According to the questionnaires, participants embrace more sense of altitude and dread of height and lose sense of postural stability under VR condition, which can engender additional stress.
The ultrasound positioning technology used makes it possible to collect the data of the nursing activities consecutively for one week in the respiratory disease center of the Showa University Hospital. The total of 142 person-day and 1,464 person-hour of nursing traffic line data were collected. The nursing activities were visualized in motion picture, and the room-to-room movement patterns were visualized in network models. Analysis of the data clarified the length of stay according to place, the length of traffic line of each nursing staff. According to the nurses’ attributes, the resultant data showed the characteristic nursing activities.
The spaces between buildings play various important roles in the residential environment. To describe and analyze the characteristics of these spaces, present paper developed a program using an AutoCAD application, which measures their lengths and widths automatically. Although this method serves as a criterion applicable to various aspects of evaluations, herein it is employed to evaluate vulnerabilities of residential areas against earthquake disaster.