In this paper, a fundamental study is carried out to develop intelligent concrete with self-healing capability for prevention of water leakage. Conceptual methodology consisting of three functions of sensing, processing and executing is proposed. In the method, crack repairing agents are installed as core materials in shell bodies embedded in concrete structures. The feasibility of the proposed approach is clarified experimentally by making use of glass pipes as shell bodies containing crack repairing agents.
Based on the experimental results of strength-development behavior of massive concrete blocks, we propose a new idea of concrete strength control method for the concrete of using the B-type fly-ash cement and the fly-ash compound moderate-heat cement. (1). Concrete mix may be designed that the concrete strength of massive structures in situ satisfies the specific design strength until 13 weeks of concrete ages, not at 4 weeks. (2). Standard curing specimens are tested at 4 weeks for the strength inspection. (3). In the case where the specific design strength is under 360kgf/cm^2, the acceptable strength is more than the specific design strength. In the case where the specific design strength is over 360kgf/cm^2, the acceptable strength is more than the specific design strength plus 50kgf/cm^2.
Since 1979, we have designed and built houses that had cavity walls with concrete blocks in order to make masonry constructions appropriate for a cold climate. Styrene foam boards 100mm thick are put on the outside of the inner block walls that are load bearing. The outer skin of the 120mm thick block is tied to the inner structural wall with 13mm steel bars. In 1996, we built a new double block house with improved insulation and compared its thermal performance with that of a wooden house which had about the same specification. The kerosene consumption of the block house for space heating was 50% less and the room temperature on the day with the highest temperature was about 3℃ lower than those of the wooden house.
A compact concrete pumping apparatus was developed to evaluate the pumpability of concretes and its applicability as a testing apparatus was studied. Validity of the testing apparatus was confirmed by the pumping experiment of concrete made of normal, recycled and lightweight aggregate. Furthermore, comparison with the pumping experiments of the mobile concrete pump was made using concrete with three different water-cement ratios. As a result, it was concluded that the comparative assessment of concrete pumpability according the type of concrete may be possible by using the compact pumpability test apparatus when the change in concrete quality before and after pumping and the pressures in the pipes are measured.
We have developed a new humidity controlling material using porous soil "allophane". It was found that the rate of moisture adsorption of this material was about higher than that of wood and this material has good performance of humidity control in the small chamber experiment Effects of this material in the living space were examined by using two test houses for one year. One is putting this material on the wall. The other is putting popular vinyl wallcovering. It was cleared that this building material could decrease humicdity change and the amount of dew condensation in the living space.
Recently, dome structures have been constructed in high snowfall areas. In such structures, snow accumulated on the roof is often removed by sliding. There is not enough data about a snow accumulation shape to design the appropriate snow space below the eaves line. So, it is important to study the snow accumulation shape. This paper deals with field research and snow sliding tests on stainless steel cladding for largesale structures constructed in Sapporo, and proposes a method to predict snow accumulation shape below eaves line.
An elastoplastic damper utilizing continuous plastic bending of thin metal rods, which are made of aluminum, copper, or steel, is developed. This new type of the damper is composed of two racks, four pinions, some thin metal rods, two rollers which wind the rods around, and guide rollers. The resisting force characteristics and fatigue strength of the damper were measured using a shaking table. And the elastoplastic damper is applied to the equipment in a building on purpose to decrease seismic responses. The application range of this damper by using floor response spectra is discussed.
We have performed comprehensive study on the application of visco-elastic dampers (VEDs) to seismic strengthening of existing buildings. It includes (1) experimental study on mechanical properties of several types of VEDs, (2) analytical study on the seismic strengthening of buildings by VEDs which are represented by Maxwell or Voigt model, and (3) dynamic loading tests of some full-scale bracing-type VEDs to assure their effectiveness and reliability. The study is also performed on appropriate production and quality control systems. Then, we have completed our study through many practical works and the results of the study is summarized here as the recommendation.
In this paper, various soil data, observed seismic ground motions and microtremor data have been collected and compiled in Tokai area and Nagoya city. Now we have over 500 seismic observation sites in Aichi, Gifu and Mie prefectures, and over 300 points in and around Nagoya city have been examined by microtremor observations. Database are totally organaized and is opend to public by use of WWW. Such data are important for the newly developed performance based seismic design and the seismic damage estimation for urban disaster prevention.
This paper shows the result of the lateral load test of the combine structure with the steel pipe-concrete hybrid pile and the steel pipe column. This type of structure is often applied to the over-truck buildings. When we design these buildings, it is important to know the behavior of pile and column-pile connection during seismic loading. The upper pile section of 12m is reinforced by a steel pipe and the steel column is embedded in the top of the pile. The column-pile connection which was used in the test showed the preferable performance under the big horizontal displacement.
Changes in earth pressure during the installation of a bored pile are measured using "geo-cells" which have been buried around the piles. Four piles are tested ; two of those are installed by the simultaneous burial method, one by normal pre-boring method and another is driven by a hydraulic hammer. For bored piles, the effective lateral earth pressure at the level of pile tip measured by geo-cells decreases first according the penetration of drilling rod and then turns to increase and records the maximum value when the tip of the rod reaches the geo-cell level. These features are similar to those of driven pile. The residual earth pressure after installation by the simultaneous burial method even keeps larger value than the inherent earth pressure before installation.
This paper describes a bearing capacity formula for steel pipe pile with four helical wings. The pile can be possessed high bearing capacity because of being screwed in with lateral soil displacement. 21 vertical loading tests, in which a new measuring system for axial strain of the pile was devised, were performed to evaluate the bearing capacity of these piles in various fields. A convenient bearing capacity formula, which is considered as a sum of end bearing capacity of the pile tip and four wings, is proposed based on the test results.
NUPEC has been planning the ultimate strength test of 1/4 uniform scale PCCV imaging severe accident. The pre-test analysis will be compared with measured data. This paper deals with several techniques to obtain physically reasonable analysis results with better convergence up to 3.8 times design pressure.The pre-test analysis was performed using axisymmetric global modeling based on these techniques. Concrete cracking governed the global behavior of PCCV. That is, the reduction of concrete stress due to cracking caused the changes in stress distribution of rebars and tendons and resultant global deformation behavior.
The structural system of long life reinforced concrete buildings should be selected as the total cost of the construction cost and the seismic damage cost will be minimum. We investigated the most suitable structural system of long life reinforced concrete buildings by using the total seismic cost index for the two case, which are the 100 years used period and the 200〜300years. The results make us clear that the order of suitable structural system of long life reinforced concrete buildings is that the first structural system is the base isolation system, the second one is the seismic response control system, and the last one is the ordinary system.
A tall reinforced concrete stack in height of 200m, is reported on the structural design scheme and construction method. The stack has a trapezoidal plan with cut backs at four corners. Structural performance under strong winds was monitored in the wind tunnel tests. New construction system is adopted including development of bond preventive slip form. Wall foundation concrete pile contributes to producing a stable continuous structure system.
A construction method for multiple dwelling house up to three story using prestressed concrete hollow core panels ('SPC panels' in following) was newly developed. SPC panels have been usually used as nonstructural walls. Even though SPC panels do not have shear reinforcement, it may be possible that members except SPC, such as anchorage bars, are set to yield before cracking of SPC. In this report, based on a erection test and a shearing test, availability of this method is estimated. As results, it is recognized that term of work and cost of erection are allowable, and that SPC shear wall has enough strength for 3-story apartment. The points of future improvement are also made clear.
A shear wall building construction method was newly developed for several story dwelling house. Prestressed concrete hollow core panel ('SPC in following) that has been usually used as nonstructural walls, is applied to shear wall in this method. SPC has no shear reinforcement, therefore it is the point in structural planning that members except SPC, such as anchorage bars, are set to yield before cracking of SPC. In this report, based on a shearing test of SPC shear wall structure, the limit stress of SPC is estimated to confirm that the maximum stress of SPC is less than the limit stress. As a result, it is recognized that buildings with SPC shear walls have enough anti-seismic efficiency, and that SPC is safe from cracking.
This paper reports on the structural system of a high-rise building with rectangular plan and the structural design of a 24-story apartment building. The structual system consists of rigid frames and "I" and "H" shaped multi-story shear walls. The "I" shaped shear walls with boundary girders resist against seismic force in the span direction. The "H" shaped shear walls which webs work, and two rigid frames are placed in the longitudinal direction. Loading tests of shear wall models and the dynamic analysis of the building were carried out to study the characteristics of the structural system. It was confirmed that the deformation and energy absorption were evenly distributed in all stories using the structural system in design.
The purpose of this paper is to calculate the resistance factors for flexural strength and shear strength of prestressed (reinforced) concrete (PC (PRC)) members. Variations of the strength are evaluated by the following three factors ; (1) differences between specimens and actual members, (2) accuracy of equations to estimate, and (3) uncertainty about mechanical properties of materials and scale effects. These three factors as random variables are investigated using available statistical data and methodology of a Monte Carlo srimulation. Results obtained herein show that the factor (2) above has the biggest influence among three factors. Furthermore, resistance factors are calculated by using the results of the variations.
The large-sized silos for coal of thermal power plants are under construction at Tachibana-cho, Anan-shi in Tokushima prefecture. The lift-up method is adopted to erect the roof structure located on top of the silos. This method is one of very effective erection methods of steel structures because of improvement of safety for erection and reducing materials for temporary supports. In this project, the working space is so small at the top of silo that it is difficult ot set up the lift-up equipment. To solve the problem we developed the new jack supporting system using the characteristic that the cylindrical shell is able to resist for bending force out of plane direction. This paper reports the developing of the new jack supporting system in the lift-up method.
In this paper, a method for seismic damage prediction of columns, beams and joint panel zones in steel rigid frames was proposed utilizing the results of the earthquake response analysis. In order to evaluate the applicability of the proposed damage prediction method, the damage prediction and the earthquake response analysis of three different configuration frames were carried out. Comparing the results of the prediction and the earthquake response analysis, it was found that the proposed method could approximately make a safety-side estimation of the members' damage obtained from the earthquake response analysis.
In order to investigate the elasto-plastic behavior of composite frame structures consisting of steel beams and reinforced concrete columns, a full-scale three story and two bay (2.8m story height and 5.5m beam span) frame was tested under cyclic lateral loading. The response of the structure was quite ductile and reached its mechanism with plastic hinges at the beam ends and the first story column bases. No serious damage in beam-column joints except some outer beam-column joints were observed throughout the test.
Himeji-jo Castle is visited by numerous sightseeners every year. In order to derive fire safety measures for the visitors' safety, 1/25 scale model experiments were carried out to characterize the smoke movement in the castle's main tower. The experiments demonstrate interesting effects of the architectural features of the castle to the smoke movement. The tests generated detailed information on the distribution of smoke for different fire scenarios ; zones left safe and others invaded by smoke. Integration of these results with the evacuation characteristics of the building should be essential for the func- tional life safety planning of the castle.
The purpose of this paper is to make the influence of spiral reinforcement clear on the fire endurance of CFT columns without fire protection experimentally and to formulate relations between the load bearing capacity and heating time. The following findings were obtained from the test results. 1) Relations between the quantity of spiral reinforcement, axial force and fire resistance time were cleared, and the formula considering the spiral reinforcement for load bearing during fire was made. 2) When axial force ratio is under 0.5, the lower the axial force ratio is, the better fire endurance of CFT columns with spiral reinforcement is. When axial force ratio is over 0.6, spiral reinforcement has no effects on fire endurance. 3) When axial force ratio is 0.3-0.5, CFT columns with spiral reinforcement maintain load bearing capacity under fire for over three hours without fire protection.
On November 17, 1998, a fire broke out at a hotel (Tenzankaku) in the Shirahama hot spring resort, in Wakayama prefecture. When the hotel fire occurred, there were 78 people in the hotel and they were not injured, fortunately. To discover how they could escape to safety, a questionnaire survey was carried out about hotel employees' action. The results of the survey are as follows : (1) The main factor for sensing an unusual occurrence was to smell something burning and for perceiving fire was to see smoke propagation in the hotel. (2) Among the initial action taken by employees after perception of fire, it was to determine the fire condition and to transmit the information to other people. (3) It took an average of 22 minutes from sensing an unusual occurrence to perceiving fire for employee to fulfil the evacuation guidelines. On the other hand, in the case of employees not fulfilling the said guidelines, it took an average 17 minutes.
An interview survey was carried out on the hotel employees concerning the human behavior in a fire at Shirahama. The employees were interviewed about time interval from awaring unusual occurrence to evacuation start. The information obtained by the interview survey was arranged as the figure of the time series. The time axis of the figure refered survey of fire brigade and so on. Further, the figure which indicates the condition of fire, the propagation range of smoke and burnt odor and human behavior in initial fire was developed. As the summarization, it was clear why human evacuation was successful in this hotel fire.
Design and post-application evalution of the recently completed regional safety system aided by local cable network in Takayama-Sanmachi Preserved Historic District is reported. The network is designed to detect and transfer fire alarm signals to neighbors, and an attempt is made to include emergency signals from aged families.
This paper describes several experimental results of the vibration response characteristic making use of the Concrete Slab. The flowing conclusions have been obtained. First, the test bodies are homogeneous. Second, effect of damping of damping material is different with the material of one dimension and the two-dimensional material. Third, there is dissipation of the energy to the support structure by the way of supporting it. Last, Effect on a vibration reduction by putting a damping material could be confirmed.
This paper presents the comparisons between the field experimental results of fire in a high-rise building with a void space and the computational results by a standard high-Reynolds number k-ε model. In conclusion, the computational air flows and temperatures in the void space are locally higher than the experimental results because the computational results by the k-ε model with Boussinesq approximation overestimate the highly-buoyancy flows. However the inflow rate into the space and the averaged temperature in the space agree with the measurements relatively.
Blown sand is a serious problem for the inhabitant in the coastal area. The damage is especially serious in the district facing the Japan Sea where seasonal wind is very strong in winter. In order to reduce the strong wind which causes the blown sand, the wind break fence and the net are widely used. But such measures have a problem that the perspective and the landscape at the coastline are much prevented. In this study, the new type of countermeasure for mitigating the environmental problems due to the blown sand is developed. Here, the blown sand is prevented by spraying the clod generated from the chemical industry as the waste. The performance of developed method is tested based on the data of field measurements and wind tunnel tests.
In this study, emission rates of Aldehydes and VOCs were investigated by using a small scale stainless steel chamber, ADPAC (ADvanced Pollution and Air quality Chamber). The ADPAC system, as defined by ASTM and ECA, is consisted of a small chamber and purified air supplying unit which supplies humidified controlled air at a given ventilation rate. A stainless steel seal box with Teflon sealing was utilized to control chemical emission only from the oneside surface of the test piece. Air quality of the chamber was measured without a test piece to make sure that the background concentration inside the chamber was negligible. Emission rates from wallpaper adhesives pasted on plasterboards were investigated. The test pieces were produced at the day of measurement, and the first measurement was conducted 15 hours after the production of the test piece. Measurements were repeated 4, 7, 14, and 28 days after. Emission rates were higher in the earlier period, but decreased rapidly after 1 or 2 weeks.
With the use of a seasonal change in the solar altitude, a solar control window was proposed, which can change both solar, visible ray transmittance and solar heat gain factor according to the control purposes, by using the rotating blind with the various shaped and different thermal characteristic slats. The window can decrease solar heat gain, while increasing the use of daylight. This paper describes the principle of the solar control window and its solar control performance by developing a performance simulation system. Next paper describes the estimated simulation results of its energy performance with the use of a typical office building model.
In this paper, we describe the cogeneration system planning for complex building like apartment house and office building in urban development area. And we compared the energy system simulation data and the operation data by actual measurement. The study results show that the simulation data are almost corresponding with the operation data. Furthermore to improve on energy system simulation accuracy, there are the necessary of energy demand unit data for various type on building and the correction for refrigerator operating load factor and heat exchanger input temperature.
Physical parameter of the windows of 24 apartment of the students in Kyoto city were measured. Questionnaire about importance and satisfaction with windows were done on the 248 students. The results showed that the correlation between "openness", "existence of daylight" and physical parameters were not so large. The major factors which students need for window were "daylight", "ventilation", "lack of noise", "comfortable temperature" and "openness". The largest factor obtained by factor analysis was "continuity to the outside". The importance of "observe the weather", "feel time lapse" whose loading scores were large on the largest factor were small.
In this study, functional sustainability of water supply system and electric supply system in an emergency of the hospital buildings in Tohoku area have been surveyed by questionnaire. There were problems in the suppling hours of water and electricity. However after Hanshin-Awaji earthquake, about 60% of the hospitals have checked the security of equipment, and 25% have repaired the system for emergency. Preparation and reexamination of emergency equipments are tend to be enforced in large hospitals.
It is important to reduce the energy consumption and carbon dioxide discharge in residential buildings, since energy consumption at the operational stage of such buildings exhausts heavy weight of carbon dioxide in life cycle evolution. In order to suggest plans to reduce these in daily life, hyper-texts are developed to save energy consumption in residential buildings. These volumes are estimated by answering simple questionnaires and saving senses in life-style are diagnosed to enforce higher reduction of them. These contents utilize the relation between the senses of energy saving and energy consumption, which has been investigated by means of questionnaires for residential buildings in Kobe city. The result shows that the energy saving consciousness is getting higher while the energy consumption decrease, and is less in higher range of the energy consumption.
A method has been developed to effectively and concisely record maintenance performed on air conditioning systems. Here, to represent the nature of faults and to enable maintenance record to be selected, classifications are established for types and severity of loss, mode and mechanism, and information for predicting faults. Maintenance mode is classified as a combination of maintenance policy and maintenance measure. The basis for determining maintenance expenditure, which must also be recorded, is classified as well. Several examples of maintenance records using the above classifications are presented.
"nLDK problem in housing unit plan" is to be the area of stick. If this area became outside, the relationship of private room and family room become dim. Now, family exists in "Do family." So, "Living in type" is better. This new standard plan is "New living in type". Open and flexible. By "big common and double living room", we developed a new style housing plan which connects family's member.
This study considers to review the renewal characteristics of forty five hospitals which constructed with a theory of modern hospital planning, in 1970s. This investigation results can be concluded as following : (1) Five years after completion, the number of renewal project is still less. It gradually increases and reaches maximum in ten to fifteen years, at this period, the renewal project approximately for two years. (2) The frequency perhaps reduce gradually after fifteen years. At this period, the main focus of renewal project is reconstruction of building facilities, especially maintenance for utility, interior, and equipment. (3) It is common that a high-frequency renewal causes the bad condition in the hospital environment. Therefore, the fundamental problem is site maintenance for building and landscape environment.
The Century Housing System (CHS) is one of the early systems applied to newly-built houses for their long-lives. It is 15 years since the first CHS house was built. Some interviews were held about 6 CHS houses and questionnaires sheets for dwellers were distributed at two of them. This paper is made mainly of the questionnaire statistics and the interviews are used to refer to some related problems. The openings for inspection are not used very frequently and estimated by more frequent users like building managers. The long-life of the structure and the effectiveness of the plan flexibility and the building component part changeability are not sufficiently proofed because of the short term after the completions. The problems on the long term maintenance of building components and information for the dwellers on the CHS are brought up through this research. Especially for multi-family dwellings, the long term maintenance of the common building components and space should be considered to realize their total long-lives.
The aim of this study is to make clear the relationship between the Kawasaki citizen's acknowledgement and awareness on the preservation of local heritage sites. We discusses the local heritage of Kawasaki City in Kanagawa Prefecture. The study was approached by sending out questionnaires related to preserving heritages to nine hundred citizens. We were able to come up with the following results : (1) Most people want to preserve natural site, and many visitors to the sites are neighbors' citizens. (2) It is important for people to be familiar with their heritages. (3) Length of living and age correlates with a large number of visits. (4) Awareness of preserving and acts of visits are mutually related. Thus, it is important that we carry out the educational plan.
The design guideline which decoded the historical context of the campus is necessary for its individuality and succession of traditional and historical space. In 1997, a design guideline of Waseda University was made and the comprehensive campus plannings was begun. On this paper which is a case study in Waseda university Nishiwaseda campus, we clarified the importance of the space composition principle in making design guideline based on the historical context which is useful for medium and long term campus plannings.
For local governments and urban residents, the necessity of making master plans in neighborhood level is increasing. When they make such type of master plans, what kinds of element plans should include is very important. Neighborhood planning programs are well established in the U. S. A. The purpose of this paper is clarify the outline of the recent situation of neighborhood plans, especially plan elements and their contents.
The urban redevelopment has been obtained results mainly on the development in the strongpoints by improving the project regulation corresponding to various problems. Nowadays, the situation of the urban redevelopment is changing. It is needed to objectively evaluate and socialy position the whole of the result of projects in order to continue the urban redevelopment projects with a large public investment. In this study, we suggest a new method of establishing the various subjects of the evaluation based on the results of projects and relatively evaluating the total results of the individual projects using the same regulation.