Ultra high strength concrete with silica fume was manufactured in a normal ready-mixed concrete plant. Properties of fresh ultra high strength concrete including minimum power load of mixer at discharge, slump flow and 50-cm flowing time were measured and discussed in terms of water-cement ratio, dosage of superplasticizer and mixed-up temperatures. It was proven to be possible for conventional ready-mixed plants to manufacture an ultra high strength concrete with favorable early-age properties up to 120 minutes after mixing.

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In the case of concrete used for CFT columns, the variation in the compressive strength is considered to become large near the diaphragms. However, the mechanism that results in the large variation in the compressive strength of the concrete with near the diaphragm has remained unclarified. In this study, the distribution of the compressive strength of CFT columns were verified by experiment. And many construction experiment results were analyzed and an equation for the mix proportioning strength of concrete used for CFT was proposed.

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This study deals with a proposal on the methods for investigating modular sizes of masonry units, components and buildings in historical masonry in Meiji and Taisho era. The methods aim at solving the view of the module at that time on the basis of a series of investigations of brick masonry buildings by proposing the module dimensions which are defined the total sum added joint width and brick product dimensions. The unit module is clarified as a quarter of the module length of masonry units so that the concept of unit module leads to the clarification of the features of modular coordination.

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This study was made to prevent tile facing on external walls from delaination. A adhesive strength test and a deformational performance test were conducted while varying the type of the base and the mode of base conditioning. As a result of the adhesive strength test, it was found that the concrete base provided higher bond strength than the mortar base regardless of the mode of conditioning and thus ensured satisfactory bond condition. The defor- mational performance test found that the tile facing applied to chipped concrete surface recovered well from deformation but the facing on unconditioned surface performed poorly. It was thus concluded that evaluating the capacity of preventing the spalling of tile facing by deformational performance test was more desirable than based on the result of a adhesive strength test.

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Steel sandwich panels with polyurethane formed core and cold-formed steel surface have been widely used for the material of building walls and roofs. Regarding to the roofs particularly, there is an obvious difference of temperature between the outer surface exposed to sunlight and inner surface of the roofs and research works on thermal stresses and deflections of the panels have been conducted. However, the behavior of entire roof systems including steel sandwich panels, the longitudinal joints and supporting frames has not yet been well explained. This paper studies the behavior of steel sandwich panels with longitudinal joints exposed to solar radiation and reports the data analysis.

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For the effective application of column-field-welding-robots, it is essential to maintain the welding sites convenient for their setting and traveling, and also to improve the accuracy of steel members so that the variation in the sizes of the welding gaps doesn't exceed the allowable limits for the robots. For the purpose, the authors have developed a new steel work system utilizing plumbing adjuster of steel column and high precise measuring system, which enabled effective application of column-welding robots and quicker progress of steel erection.

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The author have developed a plate-type mechanical blade system attached to static blade end, aiming at rational mixier arrangement. In this paper, the unconfined compression strength and vertical capacities of mixer were experimentally investigated for various of loams. As the results, it is verified that the construction quality of the mixer can be evaluated with the generalized superposed sterngth theorem and their high quality are satisfactory against loams.

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In general, a crack scale is used for measuring width of a surface crack in concrete structures. However, it seems infeasible from the standpoint of promotion and optimization of the method of a non-destructive testing for practical use. The purpose of this study is to develop a mobile crack measuring instrument and to evaluate the fundamental characteristics when use on various construction materials especially in measuring mainly width of a crack in concrete. As a result, the followings as the extent of measurement to be applied depending on the shape of a crack, an effect by characteristics of building surface materials, an effect of finishing colors, an effect of the roughness of the surface and an effect of skills of the measuring person became clear as pertinent in practice

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For developing a simple and easy joint method of PCa-CFT, experiments were necessary to establish the grouting method, by which the gap at the joint can be filled properly. In this experiment, flowing conditions and void ratios are measured by the following variables. 1) Section size of steel tube, 2) Position of grouting injection inlet, 3) Position of the exhaust, 4) Interval of filling gap, and 5) The grouting pump form. As a result, The most suitable grouting method to restrain a void ratio of the gap in less than 2% was found.

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In Japan, since the new code for base-isolation design was established in 2000, all of the isolation devices shall be pre-qualified by the government. In the pre-qualification, manufactures are required to submit various technical data supported by experiment. A working group of JSSI has been working for survey and analysis, in order to provide useful technical information of rolling bearings to the structural engineers. This paper presents the summary of those investigation-results of the rolling friction characteristic: limit compressive strength; compressive-stress dependence; velocity dependence; gradient dependence by setting.

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In Japan, since the new code for base-isolation design was established in 2000, all of the isolation devices shall be pre-qualified by government. In the pre-qualification, manufactures are required to submit various technical data supported by experiment. A working group of JSSI has been working for survey and analysis, in order to provide useful technical information of sliding bearings to the structural engineers. This paper presents the summary of those investigation-results of the sliding friction characteristic: velocity dependence; compressive-stress dependence; temperature dependence; repetition dependence.

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In addition to earthquake-resistant construction of dwellings, we must consider the indoor space safety from the viewpoint of casualty. We developed a diagnostic system aimed at seismic indoor risk reduction based on the evaluation algorithm of seismic casualty risk potential in dwelling space and of evacuation risk to outdoors. This computer system enables to make diagnosis of indoor safety easily and to support a safety arrangement planning of furniture, and besides to specify the victims of the family, the dangerous space in the dwelling and the risky zone of twenty-four hours a day as appropriate information to take countermeasures.

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This paper presents the changes along passages of vibration characteristics for a high-rise steel building based on microtremor measuring data. The building is 120m height, rectangular plan and it was completed in October 1998. Many data are simultaneously collected in two horizontal directions and torsional direction on each measuring floor since January 1999. It is clarified that natural frequencies and damping ratios at every direction or in each mode are decreasing gradually along the passages of time. Further more, natural fre- quencies measured on same date are different in each measuring time. Stan- dard deviations and coefficients of variation are applied to consider the variation characteristics of natural frequencies on each measuring date.

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This paper presents the changes along passages of vibration characteristics for a high-rise steel building based on microtremor measuring data. The building is 120m height, rectangular plan and it was completed in October 1998. Many data are simultaneously collected in two horizontal directions and torsional direction on each measuring floor since January 1999. It is clarified that natural frequencies and damping ratios at every direction or in each mode are decreasing gradually along the passages of time. Further more, natural fre- quencies measured on same date are different in each measuring time. Stan- dard deviations and coefficients of variation are applied to consider the variation characteristics of natural frequencies on each measuring date.

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In recent years, the base isolated structure is adopted as the building of various uses, with the apparatus which should be prevented from micro-vibration. Base-isolated buildings are divided from ground. Accordingly it's said that base isolated buildings may be disadvantageous in term of micro-vibration and it's important to predict the characteristics of vibration easily in term of planning of buildings. This paper describes a method of response analysis of micro-vibration in base-isolated buildings, adopting simple model which based on same value of planning and using it to simulate vibration responses.

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Vision-based motion tracking technologies including marker-based point tracing and image-based edge recognition methods with surveillance cameras were applied to measuring earthquake induced motions and detecting the damage of interior elements during earthquakes. Shaking table tests were carried out to evaluate the optical system's ability to detect structural collapse and overturning of interior elements. The movement of two-story frame structures and rectangular pieces of wood on the shaking table were monitored using conventional video cameras. Results from this exploratory study show that optical measurements are promising in terms of capturing small to large deformations and identifying various kinds of seismic damage.

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The ultimate capacities of a natural rubber bearing are defined by compressive stress, shear strain, and stabilized restoring force. The experiments were conducted with parameters of shear elasticity (G) and second shape factor (S2) for rubber bearing. Considering with test results, the ultimate capacities were verified, and furthermore the influence of those parameters were clarified. Additionally, using test results, stable deformation of rubber bearings for designing was proposed.

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In applying "Response and limit strength method" to seismic design, the design seismic load on surface strata is affected by the selected level of engineering bedrock, the measured and/or predicted shear wave velocity. In result, the required strength and response displacement of structure varied. This paper examined the effect of variations of design seismic load evaluation on required strength using a response spectrum method proposed by Miura et al., the notification methods, and SHAKE. Structural engineers must have an appropriate engineering judgment on setting soil model.

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To enhance the seismic performance of high-rise building during earthquakes, hybrid damper system has been applied to the building. This system consists of hysteresis damper, which performs well when it is deformed, and viscous damper, which is effective regardless of deformation. This study investingates the performance of the hybrid damper system to control vibration by conducting response analyses using a lumped mass model and a 3-dimensional member model.

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Reinforced concrete HP shell water tower should be checked to the current seismic load requirements by the ultimate strength approach. There should be strong soil-coupled effects of top-heavy structure;however, the vibration characteristics of those structures have not been well investigated. In order to provide a linear elastic model beforehand, we have measured micro-tremor to find soil-coupled and base-fixed vibration characteristics of the structure. Moreover, we have measured micro-tremor on the ground surface around the structure and simulated H/V spectra and dispersion curves with the Rayleigh wave fundamental mode to help incorporate proper soil model into soil coupled FEM model.

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Small diameter steel piles have been increasingly used to reduce the settlement of small buildings on soft ground. The evaluation of the load carrying performance is essential for these kinds of pile especially after the enforcement of "Quality Secure Law for Houses". A rapid load test by Falling Mass Method is developed in which a cushion is inserted between a hammer and the pile head to elongate the loading duration. A number of rapid load tests by Falling Mass Method are carried out to investigate the feasibility of the method. The test results show that a good agreement is obtained with the conventional static load tests.

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In construction process of small size rotary penetrated steel pipes, screw shaped guides attached to the pipes largely improve construction efficiency. On the contrary, the guide screw reduces the frictional resistance of soil around piles if the size of guide screw is too large. In this paper, effective size of guide screw is investigated through a series of loading tests carried out in actual muddy soil. The diameter of steel piles used in the test is 114mm, and different three sizes of guide screws are examined and compared with plain steel pile. As a result, it is concluded that enough frictional resistance can be expected and, at the same time, energy consumption can be reduced to 20% compared with plain pile, if the diameter of the screw is over 210mm.

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It is the purpose of this study to clarify the development of snow cornice on buildings and the relationship between snow cornice and meteorological elements. Therefore we carried out field experiments with the model building and observation of snow cornice in Asahikawa, Hokkaido, Japan. The fol- lowing results were obtained. (1) Snow drifts in front of parapet have a great effect on the formation of snow cornice. (2) Snow cornice is formed by the heavy snowfall with wind speed exceeded 4m/s. (3) The wind direction during snowfall (over lOcm/day) is closely related to the formative place of snow cornices.

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This paper reports the test method and test results of an existing wooden house built 39 years ago in Hirosaki city. Because the space of the site was small to set up the loading facilities, the reaction of the house's own footing was used to apply the load on the beams, and chain blocks were used to make driving force. The results are as follows. Although some timbers decayed and had suffered from ternite damage, the house was very strong as the lateral strength was more than 1.7 times as large as its weight. The distribution of the horizontal desplacement of the roof construction during the loading showed the force transmission of force between the wall structures through the roof structure, and the roof construction had some degree of stiffness.

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This report presented a database of shear properties of nail and screw while they are driven on sheets to timber frames. Based on our experiments varying with the thickness of sheathing materials and type of nail and screw classified as 86 types, the database table has shown stiffness, equivalent shear strength and ultimate displacement which are evaluated with method of allowable stress design for conventional post and beam structures by Japan Housing & Wood Technology Center.

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Inappropriate reinforcing methods for openings at beam-end regions could cause brittle fracture of beams in reinforced concrete condominiums subjected to earthquakes. Therefore, the openings are arranged outside beam-end regions. Consequently, large drop ceilings for storing the pipes are required constraining living space. To solve this problem, a reinforcing method for openings was developed, and the performance of beams with such openings was examined by loading tests. These tests proved that the developed reinforcing method has the necessary strength and deformability guaranteed by the design. In addition, the full- scale construction experimental result showed that there is no problem in workability of installation of reinforcement and placing of concrete in the vicinity of openings.

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This Paper reports Honeycomb structure made of aluminum alloy in "Brugge 2002 Pavilion". Honeycomb and Sandwitched-panel have completely different strength and rigidity each other. The layout of these structural elements defines the stress diagrams in the both of structure and expression of the architectural patterns. The transparency of honeycomb, directed by the diagrams, makes the space and the structure of the pavilion abstractive. The synthesis of architectural expression and structural system harmonizes the Pavilion to the town with the medieval atmosphere. The work inherits "Realization of new spatial expression by abstracted structure" in "K residence at Sakura Jousui".

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The purpose of this study is to grasp the fire behavior of a compartment fire in activation of a sprinkler system. Numerical simulations using the CFD field model were conducted. The computational results were compared with the full-scale compartment fire experiment in which a sprinkler system was installed. The CFD code, which is the improved verdion of FDS developed in NIST, was used for numerical analysis. When a sprinkler system was not in activation, the computational results of the temperature distribution and the radiation heat flux were in agreement with the experimental results. When a sprinkler system was in activation, the computational results of the radiation heat flux were to close to measurements. The computational results of the temperature distribution showed the tendency to close to experiment results in which the heat transfer coefficient on walls was adjusted. In order to improve the prediction accuracy of the temperature distribution by CFD, it is necessary to investigate further about the heat transfer mechanism on the wall covered with water films.

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The evacuation end time surveyed by the fire drill was compared with the evacuation end time by calculation. The questionnaire was performed to the evacuation drill participant. The evacuation situation in a high-rise building was considered from the above point. Like a evacuation drill, when there are few evacuation personnel, evacuation end time is decided by evacuation start time and walk time.lt is thought that there is little influence of the exit passage time.

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The purpose of this study is to grasp the efficiency of charring control of wooden column by water discharge equipment. The experiments were carried out in accordance with ISO834 fire standard curve using the furnace at BRI. The specimen, that is wooden column, was two sizes (Cross Section: 300mm* 300mm, 500mm^* 500mm, Length: 1000mm). The experimental conditions have changed the operation times of water discharge equipment, the quantity of discharged water the heating time and so on. As the results of experiments, The following tendencies were acquired; The surface of specimen is clearly divided into the portion of charring and no charring. The efficiency of charring control becomes higher so that the amount of discharged water increases.

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On-site investigation has been conducted on the distribution and other fire-safety- engineering related properties of combustible objects installed in atria of 8 office building complexes. The result reveals that the potential total heat release due to the combustible objects is less than 15.8MJ/m2 in atria used as entrance lobbies or passage ways and is within 100.4MJ/m2 when the atrium is used for temporary events.

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On-site investigation and interviews to residents are conducted on a fire in an apartment building which resulted in the notable fire and smoke damage throughout the building not lower than the floor of the fire initiation. The extensive smoke damage is attributed to the failure of the closure of the fire doors of the staircase, probably due to the aging of either the fire detecting fuses or the automatic door closers. Unawareness of the gang-ways by the evacuees resulted in the notable difficulties in the evacuation from numbers of the dwelling units.

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The purpose of this study is to propose a method to measure sensible heat flux from urban surface by using mirrors with scintillation method in order to actualize for setting scintillometers in free place of urban areas. In this paper, we designed a system to adjust laser beam angle by remote control in a short time. To evaluate our system, a measurement in which laser beam was reflected one time was performed on the field. Our system was possible to adjust laser beam angle by remote control in a short time, but our system was not avoided the misalignment of the laser beam angle which accompanies temperature rise. When measuring using the mirror, the change of the temperature and the solar radiation in 20 minutes before immeasurable time tends to become bigger than in other time, and measured values in 20 minutes before immeasurable time gave low reliability.

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In the town houses and the apartment houses in the Osaka Prefecture, the questionnaire of thermal environment and the air quality was carried out. Although there is much recognition that the amount of the air conditioning apparatus used was increased after they have moved in these houses, the residents' consciousness to ventilation and opening of a window was high, and they were trying to ventilate positively through the year. Although there were many replies that heating apparatus was also purchased at the time of moving in these houses, the activity of adjusting temperature appropriately was performed. Although dew condensation arose in the window and the window frame in winter, there were replies that it is coped with by ventilation.

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The three components of wind velocity at the horizontal angle and wind directions of three kinds of ultra sonic anemometers were measured when the wind blows from respective 30 degrees in the experiment. The stems of errors between theoretical data and measured data of each wind velocity component and between accurate data and measured data of wind direction were analyzed. Their correction methods were presented and verified. The results are as follows: 1) The extent'of errors of wind velocity components were 30-40% in maximum which were arisen by probes and their supporting and were 10% or 40% or 50% by supporting posts. 2) The extent of errors of wind directions were within 4° or 6°. 3) The correction methods of wind velocity at the horizontal angle and wind directions were presented by using quadratic equations in respective wind direction extents and were verified.

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The cross comparison of results for wind environment around building complex in actual urban area using different CFD codes are carried out, in order to assess the accuracy of CFD prediction of flow around a high-rise building including the velocity distribution at pedestrian level. The results of the analyses were compared with the experimental data.

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The purpose of this paper is to present the development of a temperature stratified type of thermal storage tank with a high thermal storage performance composed of parallel-connected tanks with a shallow water depth of 1. 5 to 2 meters, which can be installed in the double slab space under the basement of medium rise buildings. In order to achieve this object, the inflow/outflow port which enables the flow rate of port to be almost equal with one another was developed, and the effect of connecting hole through tank partition on canceling stored heat imbalance which is attribute to parallel connection of tanks was studied.

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The purpose of this survey is to clarify the status of standards on ventilation requirements for residential buildings in European and North American countries. This paper reports the minimum ventilation rate for the residential buildings in eleven countries which are described in the literatures. The airflow rate and air change rate are calculated for a model house proposed by The Architectural Institute of Japan. As a result, the values of air change rate is around 0.5 ACH in almost all countries.

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In Kitakyushu Science and Research Park, a new district energy system has been introduced. In this study, we chose this system as a case study and have carried out an analysis on the efficiency of the power generation and heat release utilization of the fuel cell and gas engine in summer by using the recorded data. The results can be summarized as follows; 1) Although the power generation efficiencies of the gas engine and fuel cell are a little bit lower than the standard designated value, they are almost running at stable condition. 2) The collected heat energy is lower than the designated value. The heat release utilization, which is used for cooling and hot water, is fairly low. Considering the efficient use of energy, it is a key to have a good use of heat release when we introduce a district energy system. 3) The discarded heat energy of the system is very big in this investigation when evaluating the system as a whole. It is fundamental to the future of energy conservation to use primary energy more efficiently.

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The purpose of this study is to clarify the effectiveness of utilizing the exhaust heat from substation. The analysis is carried out by using a management data of a building utilizing the exhaust heat from the substation to the heating system on the office floor and the hot water supply system on the residential floor. The result shows that the energy consumption of the building, including the pump electric energy for the heat carrier, can be reduced not only in winter but also in summer.

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Estimation of heat load baseline is very important and necessary for evaluating the effect of energy conservation measures in office building. In this paper we attempt to estimate heat load baseline of an office building by physical model and statistical model. As a result, the change of heat load by energy saving improvement was able to be predicted with sufficient accuracy and the merits and demerits of each method is clarified.

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In order to confirm the effect of the shield cloths, the thermal environment, especially air temperature distribution, inside an enclosed arcade with the shield cloths was investigated both in summer 2001 and 2002. At the point without the shield cloths, vertical distribution of air temperature showed a sharp slope in the upper part inside the arcade. However, at the point with the shield cloths, vertical distribution showed a blunt slope. The outside air temperature just on the arcade and under the shield cloths was higher than without the shield cloths.

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In this study, the authors conducted a thermal measurement in a building with a roof spraying system and a green roof in order to clarify the effects and problems of them on thermal environment. The results found that although there are some effects of a roof spraying system on the thermal mitigation of indoor air temperature, it is hard to say the roof spraying system is effective in an insulated building. However, the authors concluded the roof with green plants is much more effective than the roof spraying system to lower indoor air temperature.

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