Applicability of high-strength/high-fluidity concrete using eco cement to environment-conscious CFT was examined. As a result, the following conclusions were obtained. (1) Within W/C=28% or more, high-strength/high-fluidity concrete using eco cement can be placed with a usual concrete pump. (2) In the comparison with W/C=35%, high-strength/high-fluidity concrete using eco cement had a pumpability almost equal to high-strength/high-fluidity concrete using ordinarily portland cement. (3) The corrosivity of high-strength/high-fluidity concrete using eco cement with W/C=35% was smaller than that of concrete using ordinarily portland cement with W/C=50%.
After a disaster, it is needed to provide large amount of temporary houses promptly for people who lose their own houses. In this paper, a housing construction technique that is suitable for Japanese historical surroundings is proposed. It is making use of the Japanese traditional plaster technique inherited for hundreds years. And the frame of this system is the shell structure that is one of the most efficient structural system, therefore, it can be build with very little amount of material.
In order to avoid vegetation-dependant damages of waterproofing membranes for roof greening, a test procedure for evaluating root resistance of it was developed. Test procedure is as follows. Two kinds of trees and two kinds of grasses are planted in inner containers of punched stainless metal sheet, inside of which waterproofing membranes are applied, and then, the inner containers are placed in outer containers. After being raised for two years in a greenhouse, the inner containers are removed from outer containers. The test membranes are inspected whether roots penetrate or don't through them.
RFID assisted building information recording and tracing tool was developed. The IC tags were installed in the building during their construction process as a key to receive the information. In the system the visual information and the building materials' information such as the manufacturing companies and mills can be searched by the help of the code written in the IC-tags. And the detail information of the builders and the construction and renovation history of buildings can also be searched in the tool. The system was applied to the retrofitting process of the exhibition hall existing in the Building Research Institute.
“Common Specifications of Construction Work” which the Building and Repairing Department, the Ministry of Construction supervised had been used widely on public and private organizations with repeating a revision beyond the half-century since 1950. A database of these Specifications gives very effective information for estimation of the former specifications in improvement of existent buildings. Changes in specifications about the case of the steel construction on these Specifications are reported in this paper.
This study reports on the prediction for the wood construction wastes of Sendai city based on the house ledgers of fixed asset tax rolls. The survival rate of wooden houses has been supposed to follow a Gompertz-Makeham distribution. The estimated data indicates that the survival rate in 1997 was lower than in 2002-2004. The life expectancy for wooden houses in exclusive residential district was estimated to be approximately 50 years, which is roughly two years longer than the average of whole Sendai city. The prediction for wooden construction have been classified according to destruction rate and new-building rate.
This case study is maintenance situation of village environment in Chinmen Islands and Pescadores of Taiwan. The clarified on traditional materials for possession/supply/reuse in the repair work of the traditional private houses. The purpose of investigating materials security policy to succeed to the historicalness (the use of peculiar materials) of the private house while there is the limitation of resources.
Wood is the one of three main construction materials. Comparing to other two, Iron and Concrete, recycling rate of wood is low and its material flow is not clear yet. One reason of such situation is that there are so many recycling methods of wood. In this research, we tried to make real situation clear concerning about wooden construction materials which manufactured in Akita prefecture. Then we tried to evaluate effects of recycling in some lumber factories using Life Cycle Assessment tool.
The authors attempted to develop a plant-base geomaterial with vibration damping capability against earthquake motion using industrial wastes and construction by-products. This geomaterial will contribute not only to seismic vibration damping but also to urban greening. The mechanical properties of the geomaterial through the results of unconfined compressive test and cyclic triaxial test were discussed in this paper. The geomaterial mixed with wood-chips, recycled fine component and emulsified asphalt was a suitable target of the research.
A new base-isolation system for detached houses is proposed and the results of its full-scale shaking table tests are reported. The new system is based on the concept of the “gage pendulum”. In order to examine the performance of the new base-isolation system a series of full-scale shaking table test with a real detached house was carried out. After the tests the house was directly connected to the foundation and another series of shaking table tests, without base-isolation, was carried out for the comparison. The results show the high performance of the proposed base-isolation system.
In this paper, a laddery beam with high damping viscoelastic dampers is proposed to enhance seismic capacity of traditional timber structures. To make clear the effect of the reinforcement member, shaking table tests were conducted in the Disaster Prevention Research Institute, Kyoto University. As a result, a laddery beam with high damping viscoelastic dampers increased damping ratio and reduced response, compared with those without dampers. The laddery beam with viscoelastic dampers tested was proven to have effectiveness in enhancing seismic performance of traditional wooden frames during earthquakes.
The method for evaluating the difference of SPT N-values is investigated based on the nine SPT at the same site, and the trial design on bearing capacity of the pile considering the SPT N-values variations is conducted. It is shown that (1) The coefficient variation of the average N-values of the layers is comparatively small, though the coefficient variation that uses all N-values is very large; (2) The bearing capacity of the pile obtained from the limit state design is larger than the allowable stress design, if the difference of the ground constants is appropriately evaluated.
This paper discusses on performance for the passive control of structures such as bridges and space structures by using a tuned mass damper with Toggle Strut String Systems (TSSS). TSSS are deformation vibration control devices with lever mechanism having auxiliary masses, which are invented by authors. In this paper, the proposed system is applied to Pedestrian Crossing Bridges. The forced vibration experiment and micro tremor observation were carried out, which prove the effectiveness of the system and fundamental vibration characteristics of the Pedestrian Crossing Bridges.
One week after the Niigata-Chuetsu-Oki earthquake, 2007, the authors investigated damage to non-structural components, especially suspended ceilings, in six large enclosures at Nagaoka City. All of the six enclosures had damage to suspended ceilings in 2004 Niigata-Chuetsu earthquake and have made certain recovery works and improvements to their ceiling systems. In this paper the authors compare the damage in these six structures in both earthquakes and try to examine the validity of the improvements that have been made between the two earthquakes.
The purpose of this report is to grasp the behavior and the damage states of the building by wooden unit construction method at the time of a big earthquake. Then, we gave shaking table tests using fullscale model. In the size of this full-scale model, first floor area is 58.06m2, second floor area is 47.11m2, height is 7.0m and total weight was 199.1kN. The examination items are natural frequency, response acceleration, hysteretic characteristics, deformation characteristics, pull-out load of leg section, and damage states. As a result of this full-scale shaking tests, the behavoir and the damage states which are thought to be some features of building by wooden unit construction method were obtained.
A new type of moment resisting timber joint has been developed. The joint is made up of steel plates, bolts and steel cotters. The plates and the bolts are embedded with timber element of frame structure. By combining those elements with steel cotters, moment resisting joints can be constructed easily. Static loading tests of the joint have been performed, and results of the tests made it clear that the joint have rotational rigidity and strength required from constructing moment resisting frame. And when we design the structure of wooden residence, we must use the shear elements. So, we simulate of shear-displacement curves of shear elements. In this paper, we show the results.
In order to estimate the dynamic characteristics of two temples constructed by modern method, we carried out microtremor measurements. The main results obtained from microtremor measurements and analytical investigations are as follows. Natural frequency of these temples distributes from 4.3 to 5.0 Hz.Torsional angle between first and second floor is about 10-8 rad. Damping constants for translate mode distribute from 2.5 to 4 % and those for torsional mode distribute from 1.5 to 3 %. Results obtained by an analytical model considering two axis eccentricities satisfactorily coincidences with results obtained by microtremor measurements.
In order to estimate the compressive stress and frictional shear stress at the mortise-tenon joint with pin , we carried out the static horizontal loading tests. The main results obtained from these tests and analytical investigations are as follows. Within small deformation range the frictional shear stress account for about 60 percent, around yielding point about 20 percent of all stresses. The analytical model shown in Fig.1 expresses the stiffness and bearing force within yielding point.
When concrete of 100 N/mm2 class is used so that outside columns of a high-rise building may receive a high axis load, concrete at the edge of an R/C column member is violently crushed by compressive force at a story drift angle of 1/200 - 1/100 rad. To prevent this, as there were problems in structural performance as strength rapidly decreased, 1 - 2 vol.% steel fiber was mixed in to reinforce the precast concrete shell R/C column. As a result: (1) Crushing of concrete at the edge of the member and exfoliation of cover concrete were decreased. (2) Deformation capacity increased in a straight line as the steel fiber content increased and that increase was 20 % when the steel fiber content was 2 %. (3) It is conjectured that the flexural ultimate strength increased about 25 %.
The earthquake-resistant steel bar named FLS is developed for the high performance of reinforced concrete members against the earthquake by Center for High-Tech Research Fukuyama University. The mechanical property of the steel is low yield strength and high ductility. The influence of the steel bar do to earthquake energy consumption in formation of the plastic hinge of RC members is considered. This paper describes the seismic performance of RC specimens with FLS and an application example in a seismic reinforcement.
Carbon fiber sheet (CF sheet) is widely used in seismic strengthening for existing R/C buildings. But shear failure is considered to occur in R/C column even if it is strengthened by CF sheet. In the current seismic retrofit standard, effect of CF sheet is only evaluated if the increasing in ultimate strength is observed. However, some past experimental studies showed the ductility of RC column is improved by CF sheets even if the strength does not increase. This research is aiming to propose the rational evaluation for the improving in ductility of RC column by CF sheets which is failed in shear. FEM analysis was used in this examination, and the followings are obtained. 1) There is upper limitation between the amount of the total shear reinforcement(Σpw • σwy) and the ductility. 2) The improvement in ductility reaches upper limit when the ratio of the total shear reinforcement to upper bound shear strength ((Σpwσwy)/(υ σ B/2)) becomes unity.
Experimental results of new precast concrete beam-column connections constructed by post-tensioning precast beams to precast columns using unbonded tendons are presented. The connections consist of precast beams which has steel cap at its ends and precast columns which has steel band at the connection region. The steel cap and steel band are used to reduce damage in the plastic hinge region of precast beams. Four test specimens were subjected to reversed cyclic loading and comparisons were made between the behavior of presented precast concrete specimens and conventional precast concrete specimen.
Loading tests for sustainable building structural system on the past studies have not considered the axial force applied to the beam-to-column connection. These tests have also not considered the change in the rigidity with the floor. Therefore, the effectiveness of the axial force and the floor was indefinite. This study verifies the effectiveness of the floor and the axial force by the behavior of the specimens that set partial frames for sustainable building structural system of one layer one span.
This paper describes static cyclic loading tests of buckling restrained braces using steel mortar planks with initial imperfections. Experimental parameters are initial deflection of core plates due to uneven of mortar face and direction of core plates. Tests are conducted by applying increasing loads alternately in positive and negative directions. As results, the energy absorption capacity of specimens with initial imperfection is lower than that without initial imperfection; however, the absorption capacity is larger than that of required value.
Seismic retrofit of tower structures by additional buckling restrainer or replacing critical members by buckling restrained braces have been proposed and took into practice by the authors. In this paper, these retrofit methods are studied with the point of view of their cumulative seismic energy dissipation capacities until the fracture of axial members. Past experimental results on various axial members including buckling effects are applied to these verifications.
The building facade plays important role for not only creating urban landscape design, but also affecting the.. environmental impact through energy consumption. Also such perimeter zones are effective area for providing seismic resisting elements in structural design. For satisfying all of these demands, the authors proposed the concept of integrated facade engineering, which treats architectural design, structural and environmental design combined together. Following the previous papers, other detailed examples of Integrated Facade are proposed in this paper, and their structural performance is evaluated through mock-up experiments.
The authors have been developing low-rise reinforced concrete masonry buildings with the wall thickness of 150mm, for the purpose of the increase of inner space of buildings, the decrease of building weight, and the usage of the standard building module of 300mm. In order to realize the buildings, out-of-plane bending behaviors of fully grouted concrete masonry prisms, using newly developed small-size units with the strength of 40 N/mm2 class and grout concrete of the strength of 40 - 60 N/mm2, were investigated. Special pre-mixed cement mortal was used for the joints to obtain high out-of-plane bending performance.
We developed Health monitoring system for the structure with Smart AE sensor. The Smart AE sensor, which included a composite transducer, CPU and memory on the substrate, transmits only important information to the monitoring system. We conducted the experiments using the health monitoring system. The system can detect the occurrence and propagation of a crack by the AE count as the index of damage. The health monitoring system with Smart AE sensor is useful to detect the damage for the structure.
The authors developed a new type of smart vibration sensor, which consists of a MEMS tri-axial accelerometer and a micro-processor on board with wireless data transmission unit. The sensor is characterized by converting acceleration data into several indices on board, which are transmitted via power saving wireless standard; ZigBee. Through the two experiments, one was to verify dynamic properties of the accelerometer and another was to confirm data transmissibility in an actual building, it was confirmed that the smart sensor could be the key component for practical structural health monitoring system, such as global monitoring system by detecting the change in dynamic properties of building structures.
The present Japanese code for resist-seismic-load requires that ordinary buildings have to behave elastically during level-1 earthquakes, and as collapse-free structures against level-2. On the other hand, there have been some reports on the events of heavy-furniture-downfalls in buildings even level-1 earthquakes. Such the furniture downfalls could cause the serious accidents resulting in injury or death. The movement called the “KAGUTENBOU-TAI” based on students' volunteer work has been launched about half and two years ago for the purpose of preventing heavy-furniture-downfalls during level-2 earthquakes. In this paper, we reported on the philosophy, history and estimation of this movement, and also discussed its challenges and foresight for the future.
In-plane shear tests and loaded fire tests on post-shear test specimens are conducted on one-story tall conventional post-beam wooden walls retrofitted with both-sides panels for the improvement of seismic and post-earthquake fire resistance. The tests have verified high shear and post-earthquake fire performance of 12.5mm thick structural gypsum board, high density gypsum fiberboard, and ceramic-siding and steel-sandwich panel external walls.
Evacuation safety requirements in China for high rise buildings are reviewed. Evacuation safety of an office building project permitted for construction in Shanghai is then assessed with Japanese performance based fire safety assessment method. The analysis has resulted in general equivalency of the targeted safety level, yet design details show significant conflicts due to the lack of expertise in fire safety technology of the local building authority.
We conducted a Questionnaire survey about the housing performance laveling system and the sound environment for residents. In addition, we conducted an survey into the explanation situation of the supplier. As a result, we got the followings : (1) The cognitive degree of the housing performance laveling system understood that residents, suppliers became high together, (2) For the housing performance whole, the explanation degree to the consumers of suppliers became high, (3) Though the indication demand for the sound environment item of consumers is high, it is not known that sound environment item is a choice item, and it is not almost done an announcement.
We conducted an experimental examination of floor vertical vibration on various movements of persons and the rubber ball impact in some floor structure. We furthermore examined the perception degree on the rubber ball impact. As a result, we got the followings: (1) The difference of the vibration response of each time is very large in the person's movement, but the difference of the vibration response of each time when the rubber ball falls is very small, (2) As for the vibration response when the rubber ball falls, correspondence with the vibration of various movement of persons is good.
This investigation was conducted for the purpose of clarifying the tendency of the indoor color of the Western-style houses, mainly in the important cultural property specified in Nagasaki, Kobe, and Yokohama. The findings are stated as follows. 1) Walls and Ceilings are mainly finished with high-brightness and low-chroma plaster, or with plaster and wallpapers of pastel color. 2) Flooring are made of wood or put down a carpet in low-brightness tone. 3) Skirtings are stained in dark tone or painted in light beige and light green. 4) Many kind of colors are used in the Western-style houses, as many kind of styles and designs are used. 5) These tendencies are similar to those of the present.
Water-closet system equipped with uroflowmetry analyzer to measure out urine flow rate and volume was developed, to improve the medical treatment environment. This is an experimental study to evaluate the performance of the watercloset system, setting up in drainage stack and horizontal fixture branch piping system. As a result of examinations, allowable measurement accuracy with uroflowmetry and the reliability of system are confirmed quantitatively, under the pipe pressure fluctuations which is given by actual drainage load. The Watercloset system can be available for 2-pipe vertical drainage stacks equipped with loop-vent pipes, under the condition of permissible pipe pressure within ±100Pa.
In this study, we conducted the investigation into the surroundings of the meteorological observing stations (AMeDAS, Local or District Meteorologeical Observatory, Air Pollution Monitoring Network System) to evaluate concerning for what a observing station should be for monitoring urban thermal environment around Keihanshin district. As a result, we could grasp the detailed situation (land cover, barriers and so on) around the targeted obserivng stations and evaluated concerning the characteristics of each observing stations. And we made a knowledge database of these results temperature.
In recent years, technologies related with mobile GIS and GPS have been progressed. On the other hand, field survey of the community environment and mapping the results with public participations seem to be effective for the community planning. But, it takes a long time and participant's great effort. Therefore, authors applied mobile GIS equipped with GPS to the field survey with public participation, to make it easer. As a result, although authors found the effectiveness of this method, there seem to be some future challenges.
A tool that assists to operate the Evaluation Grid Method (EGM) was developed. An operator of EGM can show pairs of evaluating elements by this tool. An operator can also show a figure of cognitive network directly after laddering. Because feedback is available, you can get sufficient answers. It is easy to correct mistake like shortage of some paths and loop of network. And it is available to bind result of all subjects into one figure.
A long-term investigation on energy consumption was carried out for 13 residential buildings in Tohoku area since Nov. 2002. In order to make clear the effect of low-impact life style on energy consumption, the life style menu was indicated to the occupants in 10 residential buildings, and the actions following the menu was investigated. In addition to energy consumption reported in the previous paper, CO2 emissions reduction effect by the life style menu was analyzed during a week when the low-impact life style was acted. As a result, CO2 emissions of the some investigated houses were not necessarily reduced even though the energy consumptions were saved by the actions following the low-impact life style menu. It is important to lead energy saving by low-impact life styles to CO2 emissions reduction as well.
This paper attempts to reveal the characteristic tendencies in the livelihood and community perception among nomads in relation to their living environment. For this, comparative analysis was performed on the living environments and characteristics of the perception of livelihood, community activities, etc., among the apartment settlers (urban dwellers) and nomads in the subject region after identifying them from the findings from questionnaire surveys. As a result, the following matters were discovered: 1) The nomads are highly aware of the nomadic life as they are leading today. This perception correlates with their high consciousness of the life in which they are involved closely in neighboring households. 2) The nomads are highly aware of the natural environment and also the transmission of the rich natural environment to posterity. 3) The nomads are highly appreciative of and satisfied with the nomadic life overall, which shows its correlation with the rich natural and child-rearing environments and their high community perception. In addition, study was performed on the direction and issues in living space planning for the future.
The purpose of this paper is to report the survey of the Doujun-kwai Minowa Apartments and elucidate the planning method of it. By the survey, We figured out the actual condition and found out the design change of the deep well and the stairs. It was designed appropriately for the site. Design of the elevation was put highest priority on the scenery seen from the road in front of the apartments and the court.
This paper aims to clarify the relationship between split method and it's effects.Hearing survey was condacted,the results are as follows.1)There are 3 split-types.Type I :combined care in a ground,Type II :separated care in a ground and Type III :separeted care in the separated grounds.2)The effects defer from split-types. Type I improves in physical conditions.Type II and Type III are effective way at all points,especailly type III is more effective in child care.3)There are 4 barriers to split the GAKUDOHOIKUSYO. (1) difficulty to find a site, (2) unstable operation, (3) lack of parents' understanding and (4) lack of government's arrangement policy for GAKUDOHOIKUSYO.
Tsukumo elementary school has been built with innovative planning and design as a small-scale elementary school; 6.3x6.3m classrooms and south-facing multi-purpose space etc. Since its completion, POE surveys have been conducted in order to study the differences between designers' intentions and school-users opinions and the way the school is actually being used. As a result, further useful knowledge for planning and designing smallscale schools has been acquired.
Today in Japan, school management systems or curriculums have been varied based on the easing regulations. The integrated compulsory education school is one of new school style that aims at a unifi ed primary and secondary school education system. However, there is no architectural knowledge or models for such schools. In this study, we surveyed three integrated compulsory education schools that had different type of school building. Then we indicated as follows: 1) The actual condition of students' learning and living activities, 2) the school management details, 3) the difference of students' sphere of activities by school building compositions, and so on. At last, we showed the spatial composition model for integrated compulsory education schools.
This research proposes the description of the interior space by person's aspect. SCENE BOOK with occluding edge was used as a description method. Occluding edge is perceivable while moving in the interior space. SCENE BOOK is a description method along the time axis. This volume targets several modern architecture in Japan. In the conclusion, the character of each case that was not able to be understood from two dimensional drawing was clarified by making SCENE BOOK with occluding edge.
In this study, the construction and maintenance of the thatched roofs, preserved in Cheju Island and Ullung Island, are considered. Every year, in the Seongeup Folk Village of Cheju Island, the roofs are re-thatched with strong ropes made of kaya. In Ullung Island, the roofs are re-thatched with YoungGe and YoungMaRu every other year. However, presently, the shortages of materials and of the professionals are the problems. This study attempts to record and analyze the regional characteristics of the thatched roofs so as to provide fundamental documents for preserving this folk technology.
In Tsushima Island, characteristic wooden stables are distributed. They are constructed with pillars shaped rectangle section. The distribution and the detail of the structure is investigated on this report. As a result it was realized that the researched stable of this area has simple constructing system using curved woods skillfully. The way of using woods becomes the precious reference on thinking about the utilization of future wood resources.
Owing to its character such as endurance or constructional performance, aluminum architecture is expected to fulill the capability for reusing building or building components. In this report, through the deconstruction experiment of one certain aluminum architecture, the characterristic of deconstruction of aluminum architecture aiming reuse is clarified by grasping outline of deconstruction work and analayzing amount of work (man-day), and the essentials of design and deconstruction method for reusabirility are also organized.
This paper reports an outline and an analysis of experimental construction of a new elevator addition system that we developed and reported in the previous paper. We conducted a verification of feasibility of new system through the analyses especially about construction flow, construction methods, and cost of construction, after completion of experimental construction. We also conducted the questionnaire survey about this system to many visitors to the construction site, and obtained some evaluations about advantages and improvements of this system.