This report investigates basic properties, such as compressive strength, drying shrinkage and freeze-thaw resistance, of normal strength concrete containing shrinkage reducing agent (SRA) of three brands, by same cement and aggregates as well as water-to-cement ratio (=0.5). SRA-added concretes show that compressive strength tend to lower with the increase in dosage, drying shrinkage strain is obviously reduced (more than approximately 15 %), while freeze-thaw resistance is significantly deteriorated.
Previous report said that it is quite difficult to satisfy the value of standard in the 28 day activity index of JIS of fly ash for use in concrete. First, in consideration of the fluid improvement effect, a compressive strength ratio examination which is based on the old JIS method is carried out. It was found from the test results that a compressive strength ratio is more practicable to show a concept of mechanical aspect of fly ash in comparison with the activity index of the present JIS method. Second, if activity index can presume at an early stage before 28 days, it will be thought that it is very useful on quality control of fly ash. This paper also reports the result of developing a simple prediction method of 28 day activity index.
The authors surveyed the intention of ready-mixed concrete suppliers for concrete traceability with the questionnaire. This questionnaire was designed with 9 questions on not only their intention for concrete traceability and the sophistication of it, also the expectation and problem to use IC-tags for concrete traceability. It was handed out 279 suppliers in November 2010. This technical report indicated about the tendency of supplier’s intention for concrete traceability and introducing the system with IC-Tags in 3 conditions, based on answers from 196 suppliers.
One of the difficult points of concrete traceability is that a product number or product data can not be pasted directly on fresh concrete due to its flow ability. In this study, several types of IC-Tags and concrete were unified by mixing on agitator. The behavior of IC-Tags at concrete work, influence of them on concrete and responsiveness of them by the radio wave were evaluated through the actual construction steps. Besides, suitable number of IC-Tag for reliable detection from the hardened concrete was estimated. From these results, it was demonstrated that IC-Tags could be apply to concrete traceability.
It is unusual to apply powder coating to the present Japanese building exterior. On the other hand, it has been popularized in overseas countries and over 10 years has been already passed from building completion. Durability has to be discussed in order to popularize in the Japanese construction industry field. Therefore, investigation into the actual conditions in overseas buildings has been executed. A main fruit of this research is as follows. The powder coated building exterior has not visually remarkable deterioration and also it would be expected enough durability in application to the Japanese building exterior.
In recent society, global warming caused by emission of carbon dioxide raises remarkable issues. This study investigated the quantities of carbon dioxide on reinforced concrete buildings in the Tokyo metropolitan area during the manufacturing and transportation of materials to be used.Moreover, those quantities were compared between a general RC building and a building using scallop shells. Scallop shells can fix carbon. As a result of calculations, scallop shells can contribute to the reduction of total carbon dioxide quantities because they can store carbon dioxide on their own, and achieve the carbon neutral theory.
Finishing materials are known to have suppressive effect of reinforced concrete structures deteriorations. It is useful to have shown the extent of each type of finishing material effect in order to predict the deterioration. We were carried out documentary survey on carbonation resistance and chloride ion diffusion coefficient of coating materials for textured finished and paints. According to the results, we proposed the extent of carbonation resistance and chloride ion diffusion coefficient of various coating materials for textured finished and paints.
In today’s society, the wallpaper companies have been producing many types of wallpaper to meet variety user’s demands. The study analyzed on the three types of wallpaper, general PVC (polyvinyl chloride) type, natural materials type and new materials type(electrical improvement olefin), and evaluated the impression of these wall papers through sensory test. With the results of these analysis, new type wall paper is expected to improve living environment and be used in long term because it could be improved the resistivity for fragility and filth. The new one could be given an impression as same as the natural ones, and finally the study could be suggested the selection system of the flow chart optimizing the selection of wallpaper for users and suppliers.
In Tokyo, the 32-story reinforced concrete building with a multi-level car parking tower was constructed in 2000, and earthquake observation has been performed since the completion. During the 2011 off the Pacific coast of Tohoku Earthquake, the maximum acceleration over 300 cm/s2 was recorded in this building. The non-linear earthquake response analysis based on the earthquake observation records was performed, and good correlations were obtained between the records and the analysis results.
This paper presents dynamic characteristics of a gymnasium determined from recorded strong-motion response data and from microtremor tests. The results show that the fundamental periods and corresponding percentages of critical damping before the 2011 off the Pacific coast of Tohoku Earthquake changed significantly after the severe Tohoku Earthquake. The data set collected during this study contributes to the evaluation of dynamic characteristics of large space structures.
Recently, the grid-form ground improvement against liquefaction got to be used for buildings. We have many earthquake observation records including the 2011 off the Pacific coast of Tohoku Earthquake at a base-isolated building with the ground improvement. In this paper, we studied the dynamic soil-structure interaction of the building. First, the records concerning the soil-structure interaction were analyzed. Then, the earthquake response analysis was conducted to simulate the observed record using a detailed three dimensional FEM model. In the analysis, the input loss effect was confirmed. Moreover, the contribution of the grid-form ground improvement to the effect was estimated.
The authors conducted vertical loading tests on a model screw pile in a calibration chamber where the different mechanism of toe resistance mobilizing at the closed end and helical screw was in focus. Layered sand deposits were prepared in two different densities concerning relative position of the pile toe and the thin layer around it. A new formula to evaluate the toe resistance of a screw pile is proposed based on the test results. The formula shows fairly good applicability to estimate the toe resistance of full-scale piles by taking different soil modulus at the closed end and helical screw.
To investigate the influence of construction methods on the strength of soil-cement in the base bulb of bored piles, laboratory mixing tests are carried out for in-situ soil obtained from base layers of piles and for soil controlling grain size and water content. Unconfined compression tests are conducted for these specimens and those of fresh soil-cement mixture sampled from the base bulb under construction of bored piles. It is found that the strength of the base bulb is determined mainly by the effective cement-water ratio which considers the water content in the original ground. To insure the strength of the base bulb a practical measure is proposed in regard to the quantity of the cement grout mixed into the base bulb.
New passive damper device with high damping rubber was developed. Static shear loading test and shaking table test of a wood frame which the damper device was installed were conducted. The initial shear stiffness was higher than the one of conventional shear resisting element, such as plywood or wood brace. The hysteresis loop of the wood frame with the damper device was stable even under cyclic load. Moreover, a structural model of a wood frame with the damper device for earthquake response analysis was constructed. It was found that the simulated response motion of the wood frames with the dampers was in good agreement with the measured response of them obtained from the shaking table test. In the analysis of various combinations of conventional shear resisting element and the damper device, it was also found that the more damper is installed, the less response displacement become. This result is based on the feature of the high damping rubber used for this damper.
As an effective nondestructive diagnosis method without giving any damage to the mud wall on the traditional building, the ultrasonic measurement method was introduced in order to estimate their mechanical properties and shear performance and to make a diagnosis of their damage condition. Comprehensive evaluation for the relationship between the change of ultrasonic transit time and the mechanical property by compressive and shear test was performed. Consequently, it was concluded that ultrasonic transit time showed a very high relationship with the plastic behavior of the mud. On the small mud wall unit with the bamboo lath, it could obviously make grasp in its total estimation of the damage level and pattern with contour mapping by change-ratio of the ultrasonic transit time on each sector of mud wall. Ultrasonic measurement method was proved its high potential on the executive nondestructive diagnosis of traditional mud wall.
In this paper we conducted bending tests of a simple joints using lagscrewbolts with steel-wooden- members connections and analyzed those strength. For the tests paremter, we used two species of wood of wooden members two types of cross-section of steel members and chaged the arrangement of lagscrewbolts. With the proposed equation and material values on the guideline, we could estimate the bending strength. The values of stiffness from tests and equation have a little difference. In the case with Scots pine and H shape beam, that equation is precise in this study.
In this study, the structural performance of fully precast reinforced concrete beam-column joints was examined by conducting loading tests while varying the shear capacity in the panel zone, anchorage capacity of reinforcing bars of beam and the ratio of column flexural strength to beam flexural strength (axial force ratio). As a result, the structural performance was identified by comparing the relationship between beam shear force and inter-story drift angle, and between their envelopes. The adaptability of a maximum strength evaluation method was verified and the deformation capacity was identified based on the ductility factor.
Mechanical properties of concrete are important factor in the seismic evaluation of the existing reinforced concrete buildings. Maximum strength and Young’s modulus are directly related to the strength and the stiffness of the RC members respectively. Young’s modulus is concerned with the evaluation of the shear strength of the post-installed anchor bolts used in the retrofitting process. In this paper, the mechanical properties of the concrete in the structural member were discussed based on the stress strain curves which were obtained from the compressive tests.
In order to continue to use buildings that have been severely damaged by a major earthquake, it is necessary to clarify the resistance mechanism of the repaired members. Focusing on the existing buildings with low strength concrete, experimental investigations were conducted using the short RC columns damaged in shear. In this paper, it is expected that the low seismic performance of damaged buildings can be restored by epoxy resin injection alone, although epoxy injection is usually used together with wrapping steel plates or CFRP sheets. The maximum strength of the repaired columns was greater than those of the original columns.
The footing beam of the house is the reinforced concrete construction with deformed steels, and the width of the footing beam becomes narrower than conventional RC beam. Therefore a main reinforcement is arranged by one length and breadth. In late years all strength welding was developed. However, it needs a high technique. Therefore we bent a 180 degrees hook 45 degrees in this study more and developed a machined 225 degrees hook and tested the steel reinforced concrete construction footing beam using this and performed the comparison with a 180 degrees hook and the welding reinforcing rod.
RC beams without stirrups on couplers of longitudinal reinforcing bars were tested to investigate the shear performance. Seventeen beam specimens were designed and constructed with different structural details such as existence of coupler, coupler length, location of coupler, and existence of stirrups on coupler. A method to consider the specific details of these beams in the practical shear design equations was presented to evaluate the shear performance. Its applicability was examined through cyclic loading tests of the specimens.
An outline of a reconnaissance of steel school buildings damaged by the 2011 Tohoku earthquake is presented. In this reconnaissance, a total of 216 facilities have been investigated by the Steel Structure Working Group of the Subcommittee on Seismic Performance of School Buildings, Architectural Institute of Japan. The damage to structural elements, connections, non-structural elements, foundation and surrounding soil, as well as the details including building history and seismic retrofit have been recorded and the overall damage has been evaluated based on the “Standard for Post-earthquake Damage Evaluation of Damaged Buildings” published by the Japan Building Disaster Prevention Association. Not only seismic damage but damage caused by the devastating tsunami are also covered. Detailed analysis of the damage to individual structural and non-structural components are presented in following papers.
In this study, the composite structural member of plywood panel - steel is proposed. This member is consisted that the steel column is sandwiched with two sheets of plywood. To investigate the resistant mechanism and strength subjected to vertical load, the compression tests are conducted. In this paper, the parametric study is performed to investigate the effects of the thickness and the width of plywood panel. From the test results, it is observed that the maximum strength is determined by the flexural buckling, and also this combined member behaves as the layered beam.
For the seismic diagnosis of the existing wooden house, usually the general diagnosis or the detailed diagnosis of type 1 is used. The general diagnosis is the screening that the seismic retrofit are needed or not, and it’s calculation is very simple. Therefore, the seismic capacity grade of the general diagnosis should be controlled to become smaller than the one of the detailed diagnosis of type 1. However, as a matter of fact, it often happens that the seismic capacity grades of the general diagnosis becomes larger than the one of the detailed diagnosis of type 1. The reason of this phenomenon can be considered that the strength of walls except earthquake resistant walls are often evaluated larger than that of actual strength by the general diagnosis. Therefore, we propose modified calculation coefficients of the general diagnosis on the strength of wall except earthquake resistant wall based on the seismic diagnosis of the existing wooden houses. Adopting this method, we can get more accurate seismic capacity grade of the general diagnosis.
In this paper, the height and depth of the building in the region expected to tsunami inundation are calculated by compared tsunami load to necessary horizontal load-carrying capacity in the base of the building. In addition, amount of shear walls to reinforce the building and cast-in-place concrete pile to resist tsunami load are calculated. Based on these studies, structural planning flows and examples by using three building models are shown.
The purpose of this study is clarifying the basic characteristics of the smoke movement and opening jet plume in atrium next to fire room. Authors carried out the experiments about the fire smoke movement of fire source with 1/3 scale two rooms. The main findings are as follows. Flow rate of the opening jet plume has high correlation with the smoke layer height of atrium. And it increases as the rise distance to the smoke layer height becomes long.
In Japan, open-plan type classroom is getting popular in elementary schools. This planning type has various benefits for educational activities. However, sound propagation between adjacent classrooms tends to cause a serious acoustical problem. In this study, a field survey and numerical analysis on acoustical environment of an elementary school, which was newly built with acoustical consideration in its architectural design, were conducted. Based on the results, validity of the acoustical design to mitigate the sound propagation between the classrooms was examined.
The following two points to control colors on building exterior in urban planning of U.K. was demonstrated by analysis for documents and hearing from officer. 1) Colors were not controlled to be separated from other elements in landscape but to be combined with other elements in landscape under development control. 2) Colors on building exterior were controlled in consequence controlled building materials, an outdoor advertising and shop front.
The result of having performed temperature measurement in water mist atomization may be wet-bulb temperature. The air temperature in water mist atomization needs to measure dry-bulb temperature. This report presents the result of having compared with wet-bulb temperature the measured value of an ultrasonic anemometer-thermometer and thermo couple which were water mist atomization and were measured. The result confirmed a possibility that dry-bulb temperature could be measured with an ultrasonic anemometer-thermometer.
In Japan, the planning and design of drainage and vent systems for 2-3-storey low-rise houses is not clearly defined, even by SHASE-S206 “Standard for Plumbing and Sanitary Systems” by the Society of Heating, Air-conditioning and Sanitary Engineers of Japan. Hence, house development companies and building and construction companies use their own devices to design and execute plumbing work. Considering this current situation, this study aims to develop a model of a fitting having a swivel air admittance function, which is specifically for drainage systems for detached houses; verify the effectiveness of the fitting by means of carrying out evaluations on its influence on drainage performance; and provide experimental data which can contribute to the planning and design of drainage systems for detached houses.
This paper describes the analysis of the thermal and air flow distribution inside the floor-chamber and the result of the simulation of heating load which is one of some components in the air-conditioning system using floor-chamber. The temperature and air-flow were measured and calculated the convective heat transfer coefficient inside the floor-chamber. Heating load was simulated using the result of the measurement and analysis.
Through numerical simulation, the solar heat gain and thermal transmittance of a double-skin façade in a hot and humid climate was investigated using Indonesia’s climate condition as a case study and considering the orientation (east and west), the thickness, and the distance between glass skins. The results show that as the thickness of the glass skins increases, the amount of solar heat gain decreases. Similarly, the wider the distance between the outer and inner glass skins, the lower the thermal transmittance. In comparison with single-skin façades, double-skin façades exhibit the best performance at reducing the solar heat gain.
Questionnaire survey was performed to staffs of educational boards and teachers at public elementary schools with and without cooling equipments located in 22 cities of Kanto areas. The ratio of schools installed with cooling equipments were about 12% due to the small educational budget, etc. The differences of thermal environments in classrooms at schools with cooling equipments were more significant than schools without cooling equipments because environmental controls of cooling equipments largely depend on teachers’ subjective judgments. These differences were recognized by teachers except educational boards. The guidelines for environmental control were required in schools installed cooling equipments.
This paper introduces an overview of Ohori high school building built on Mar. 2010. This building was designed as an environmental conscious school that mimics the functions of a big tree. Leaf transpiration for roof top water spray, absorbing heat from roots for the Ground Source Heat Pump system, and rain water retaining for rain water storage, etc. This paper shows the planning concept and design features of the environmental conscious building introducing the concept of biomimicry.
The aim of this study is to develop a simplified Life Cycle Assessment (LCA) model for residential buildings in Indonesia, which can be used under relatively poor data availability conditions. As the initial step, a pilot survey comprising a small number of samples (n=11) was carried out in the city of Bandung in March 2011 to initiate the development of LCA model. It was found that most of the statistical data required for LCA were only available at the national level in Indonesia, while most of the residential buildings do not have design records. Moreover, the household energy consumption data were found to be not available. The results of initial statistical analyses indicated that there is a potential to develop simplified projection methods of embodied energy as well as operational energy and thus to obtain life cycle energy and CO2 emissions based on some explanatory variables such as total floor area, lot area or household income.
Measurements of thermal and air environments and hearing investigations were conducted in 2 gymnasiums of N city in Niigata prefecture where approximately 250 evacuees from Fukushima prefecture had stayed for 1.5 months. The following problems were posed through a group life: Sleeplessness occurred by noises of snores and footsteps, poor physical conditions created by infectious diseases and fatigue, cold thermal sensations caused by cold-radiation from floors and air movement, uneasiness stunk by body smell, and air pollution generated by closed environments. Some solutions were using heat-insulating materials could reduce cold-radiation from floors, wearing masks could moisten evacuee’s throat and ventilation.
Aerial photographs of a block of detached houses in the town of Takasu, Hokkaido, were used to create a 1:200 model for wind wind tunnel experiments on snowdrift formation with snow made of activated clay. The pattern of snowdrift formation was successfully reproduced, as verified by aerial photography and measurement survey. The effects of various conditions in and around the block on the formation of snowdrifts were also investigated, and it was found that windward snow piles affected the depth of snow within the town block. This result suggests the need to carefully determine the locations for piling removed snow at the block.
This paper aims at explaining the effect and subject that the new supply of the day care facilities brought by comparing the level of service sufficiency of local governments in 2000, 2005 and 2010. The sufficient occasion average was raised drastically, but the gaps increased among the local governments, so the expansion tendency of the area gap problem of welfare service supply was pointed out.
This study clarifies the actual conditions of fire safety of group home for the people with dementia and community based multi-care facility in Japan. The nationwide investigation by questionnaire was conducted. Summaries are as follows. The rate of uninstallation of sprinkler in group home in total floor area 275sq. meters to 1,000 sq. meters is 98.0 percent. In case of total floor area is less than 275sq. meters, the rate is 40.9 percent. The examination of the ideal way of the treatment and the sprinkler equipment in community based multi-care facility, are given as problem.
As the aging speed increasing rapidly in China, the number of home for the aged in Shanghai also grows fast recently. However, since there is no distinct definition of such facilities, corresponding relationship between the attributes of a facility and its general traits remains unspecific. This research intends to get a general view of the current homes in Shanghai through questionnaire. Meanwhile, a classification analysis is carried out to sort the facilities into groups with significant diversities. Statistics of attributes of the groups are given and further discussions are made to clarify the characteristics of each type of the facilities.
Recently, RFID techniques enable us to obtain enormous amount of information on positions of humans and objects in a building. This paper discusses the visualization method of customer shopping-paths in a Super-Market that are obtained by RFID techniques. For this, two different methods are applied to visualize the customer shopping-paths, which are Kernel Density Estimation method and Vector Field Visualization. By applying the Kernel Density Estimation method, it helps us to visually understand the customer existence probability density in sales floor, whereas the Vector Field Visualization enables us to grasp the customers’ flow.
The aim of this report is to recognize the significance of resident’s attitude survey for long-term refuge person by 2011 off the pacific coast of Tohoku Earthquake. Many of refuge people have taken refuge by the mother and the child, and there are many young generations. The refuge person has taken refuge because of radioactive contamination, and there is almost no damage of a building. The present negative factor is the left-behind family and the present living expenses. Future required support is housing and job support, and expects the support for a new life at a migration place.
The population of about 2/3 lives in DID now. It is a situation in which the wisdom and the knowledge of villages are not succeeded easily. A lot of environmental studies in villages are practiced. However, they target a part of a village. I paid attention the “Time-Cycle” to understand a village overall. I practiced environmental study that two calendars of pickles making made. This paper is intended to report the method and its results. Results show that this method is actually useful to understand a village overall.
This study is aimed to find the generality and the regionality of city and settlement. This paper shows the algorithm for generating subsistent settlements and boulevards which are naturally raised. The evaluation of the flatness of the land gives the expectation of the settlement locations. Then on the network consist of these settlement as node, the evaluation of the total vertical interval of the trail, and thus the optimization of the route give the future boulevards. Through the case study on Musashino Highland and Owari Plain, the efficiency of this algorithm is proven.
The purpose of this research is to study the organizational structures and activities of land banks, which are addressing the issue of vacant houses in urban cities in the U.S., and to explore whether this information can be applied to urban planning and policies for Japan. Land banks demolish vacant houses with dangerous structures or rehabilitate and sell those houses. The activities of land banks contribute to not only improving residential environment, but also maintaining home values and preventing crimes. However, these conversion efforts are on an individual basis and lack long-term planning.
In postwar historical canal have been changed by motorization and pollution among with urbanization. However, in recent years, their various functions were evaluated with vies of community development, preservation of an ecological system, historical view. In historical cities, Kanazawa city pursued some policy and maintenance of historical canal independently. The purpose of this study is to clarify policy and maintenance, management of historical canal in urban area Kanazawa, and to consider the method for preservation and maintenance of historical resources in historical city. This paper finds not only canal itself but also surrounding.
Recently, more than 450 schools have closed annually in Japan. The closed schools should be utilized as the social capital. Not only the public utilization but also the business utilization is indispensable. For the business utilization by the private institutions of closed schools, the regional contribution such as the employment of local people and the procurement from local companies are necessary. It is also required that the local governments and private institutions should cooperate together to achieve this project proactively.
This paper was organized for the awareness of disaster prevention and living environment evaluation about the disaster refuge of crippled people from questionnaire survey previous the Tohoku Earthquake. Result, has been found that many of the people of recuperation at home have not decided the location of evacuation. Moreover, people who needed assistance did not decide where to evacuate at a high rate.
The purpose of this study is to clarify the actual condition of important components of 19 important cultural landscapes designated by August 2010. By this study, the main conclusions which we found are as follows. Eight important cultural landscapes have a lot of important components that the written reports are not necessary for current changes. Two thirds of them have no regulation by the other protection systems including the landscape planning.
This paper focuses on urban design development in professional training and advisory body for local municipalities. Looking at the history of urban design in Japan starting from 1970s, methods as municipal design teams, city planning consultation, citizen participation, and design reviews were exploited. By recent inclination of collaboration with private sector, the public governance for urban design is crucial for effective and efficient urban revitalization. This paper reports on the frontier development in London by training (Urban Design London) and advisory organization (Design for London) to reveal the function and the role of urban design development in local municipalities.