In Japan, approximately 9.24 million tons of coal ash is now produced from thermal power plants, and the amount is estimated to exceed 11.4 million tons in fiscal 2013. But, the uses for concrete mixture are very limited. In this study, in order to understand the obstructive factors, we investigated uses of ready mixed concrete using fly ash. As a result, we obtained the useful information for design, construction and distribution of ready mixed concrete using fly ash.

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Among major tasks involved in the replacement of a thermal power plant are the demolishment and dismantlement of the existing plant, and the accompanying disposal of wastes. In disassembling and dismantling the existing plant, it is important to study a method to use members of the existing structure in their original conditions, to the maximum extent possible. In view of these circumstances, we studied the soundness, as a concrete material, of a reinforced concrete caisson foundation that has suffered aged deterioration. Our study revealed no such structure-related problems as concrete cracking, alkali-aggregate reaction and reinforcement corrosion. Also, the concrete compressive strength was higher than the design standard by a sufficient margin. Based on these results, we judged that the studied caisson was sound regarding its material aspects.

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This paper presents the results of a series of experimental study on the water reducing and quality-improving effects of fly ash on concrete with higher water content. Concrete mixes with slump of 12cm to 21cm, containing ordinary portland cement with and without 25% fly ash replacement, river sand and mixed sand, an air-entraining and water-reducing agent and an air-entraining and high range water-reducing agent, were tested for slump, compressive strength, drying shrinkage and carbonation. The experimental results indicated the remarkable improving effects of fly ash on reducing effects both in water content and drying shrinkage.

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Variation of quality of five kind of recent cement was investigated. As a result, the following conclusions were obtained. (1) Each cement had a stable performance in the density, the heat of hydration, the specific surface area, and the compressive strength. (2) The ignition loss of each cement was very little compared with requirement quality of JIS. (3) As for the ordinary portland cement and the Type B portland blastfurnace slag cement of each cement producing company, the chloride ion showed the tendency to increase. (4) As for the Portland cement of each cement producing company, the total alkali content showed the tendency to decrease.

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When a set-retarding agent and a superplasticizer are added, the returned concrete can be reused as a preceding mortar for concrete pumping constructions. The experimental study was performed aiming at the practical application of the recycled mortar. Laboratory tests to determine the dosage of the set-retarding agent and the superplasticizer as well as the quality of the recycled mortar were executed. Full-scale tests for the applicability of a wet-screening equipment at a ready-mixed concrete plant, and the quality and productivity of the recycled mortar manufactured with the full-scale equipment were studied.

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In this paper, we deal with the application of borehole sonar to evaluate the shape of foot protection around the tip of the bored pile. We measured reflection waves at 24 points at intervals of 15 degrees in the pile using a sonar set in the hole. Five kinds of model foot protection and a prototype were used for the experiments. We found that the shape of the five kinds of model foot protection were caught clearly by analyzing the reflection waves. And we confirmed that it was true for the case of the prototype in the field.

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In order to build the recycling system of concrete waste, a primary study for applicability of recycled fine aggregate concrete to the precast concrete products has been carried out. The study results have confirmed that a) the properties of recycled fine aggregate can be improved by the wet grinding treatment, b) the properties of recycled fine aggregate concrete can be improved by steam curing, c) reuse of recycled fine aggregate concrete is highly applicable through property improvement, and d) reuse of recycled fine aggregate concrete is highly effective in view of cost and environment influence. The study results have also proven that the material design of recycled fine aggregate concrete for the precast concrete products can be made by applying the relative quality value method.

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In construction process of surface soil stabilized ground, mixing work developed to construction work largely improve construction quality. In this paper, effective quality of mixing is investigated through a series of plate loading tests and compression tests and density tests and sieve analysis tests carried out in actual Kanto-loam. As a result, it is concluded that enough construction quality can be expected and, mixing machine compared with normal work.

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The diagnosis to investigate precisely the condition and the causes of deteriorations and the maintenance technology to repair thoroughly the deteriorations are necessary to keep a building in good condition. However, the diagnosis and the maintenance technology are often selected on an engineer's knowledge and experiments. The aim of this questionnaire survey is to grasp the practical approach and the criterion of judgment for decision of diagnosis, repair and maintenance technology utilizable in cold region, Hokkaido.

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This study paid attention to sprayed method with polymer cement mortar for renovation of reinforced concrete structure. This paper presents the results of several experiments about the working environment, the fresh and mechanical properties. It was confirmed that, construction with residence was possible except for working room, the properties of fresh mortar were moderate. The compressive and bending strength were sufficiently high, the method of the strength control was proposed. It was also confirmed that the adhesion strength was sufficiently high, and it was possible to keep the strength against hot and cold process and freezing and thawing cycles.

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This paper presents the results of deterioration investigation of the ancient airship military Hangar in Augusta, Italy, which construction began in 1917. The stability of the airship hangar is now threatened by the differential settlements of its spread footings and a research project is currently underway to strengthen the hangar. In this paper, 1) deterioration of the wall and roof, 2) bar arrangement and its corrosion, 3) depth of neutralization and included chloride ion, 4) fundamental frequency, and 5) monitoring of temperature, inclination of buttress pier, width of the significant cracks and extension of the wire are discussed.

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A new type of induction heating device is now under way to develop. It is becoming a useful tool to fix interior or exterior finishing materials to structural frames and parts of other object firmly with glue. It is quite light and to prevent construction noises and machine throbs. The purposes of the experiment were to evaluate structure materials bonded together firmly with this device and to know possibility of applying new bonding method with the device to forming on earthquake-resistant walls. The experimental results showed as follows : (1) Compared to the strength of plywood itself, beyond which the destruction must be caused, the bonding strength produced by fixing plywood on plywood firmly with the induction heating device increased, exposing itself to the temperature and humidity in the bathroom for one year. (2) The time needed to separate bonded structure materials was 1.5 to 2.0 times as much as one needed to bond structure material together. (3) The time needed to bond structural steel to plywood with the induction heating device required 40 to 50 seconds, because structural steel has a large amount of absorption of heat.

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A random variable can be concentrated at only two sample points using two-point estimate method. However, this method is not practical for a large number of variables which are not depend on each other, because total number of sample points become 2' for n variable. This paper develops a simple procedure for reducing the sample points for several random variables. Through some numerical calculations, it is confirmed that the developed method can reduce the sample points keeping the accuracy for linear functions of several random variables.

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For an evaluation of seismic risk curve based on scenario earthquakes, the location, magnitude and occurrence frequency of all sources should be specified. However, it is difficult to specify hypocenters of crustal earthquakes without surface faults, because these are equally likely to occur anywhere over an area. One of the authors has proposed a method to deal with such earthquakes as scenario earthquakes, where it has some problems. In this paper, problems for the previous method are pointed out and an improved method is proposed. It is shown that the improved method has advantage of clarity in explanation as well as improved precision in evaluated values.

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This paper describes development of the new hybrid aerodynamic vibration system for base-isolated high-rise buildings and some evaluations for wind force acting on the buildings and wind response of the buildings by using the developed system. Previous experiments for examining performance of the developed system and simulation of aerodynamic vibration of the base-isolated high-rise building in shear flow are conducted. From the result, it is confirmed that the system can evaluated not only the wind response but also the wind external force including the motion-induced.

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This paper reports seismic observation of a base isolated large building in terms of torsional vibration. The building is 8F/B2F with 90m length, 30m width, and 40m high. The isolate equipments are placed between B1F and B2F. Acceleration records and in-story deformations are measured at both ends of the building in longitudinal direction. The recorded data of Chiba-kenn-hokuseibu earthquake on 28^<th> of July 2005 showed some torsional response vibration caused by eccentricity of the building and the difference of input motions at both side. Results of a simple analytical model showed good agreements with observed records.

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Inelastic response behavior of building models with weak intermediate stories is investigated using deviation coefficient method. The method can explain well the large damage in intermediate stories and the possibility of predicting the response behavior of buildings with irregular strength distribution is shown. Also, the inelastic mode estimation method is applied to interpret the response behavior of intermediate story damage.

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In order to reduce the vibration troubles from a house standing along a railway line, three methods were tried at a vacant lot (site A). Adopting the most effective method of improvement of soil for a site B close to a railway line, the following results are obtained. The amplification ratio (2F/1F) becomes small for the transverse and the vertical components. The peak ground displacement ratio (1F/GL) becomes small for the vibration level which is larger than 20×10^<-6> meter. Accordig to the 1/3 octave band analysis, input motion of radial component of which frequency is higher than 10Hz to the house decreases.

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In soil-structure interaction problem, dynamic impedance function and foundation input motion (FIM) is fundamental physical properties. We carried out an axisymmetric finite element method (AX-FEM) analysis to verify the accuracy of FIM between "Response and Limit Strength Calculation (RLSC)" and AX-FEM. The acceleration response spectrum (ARS) obtained by RLSC almost envelops those obtained by AX-FEM in the range of the whole periods. Therefore, it can be said that the evaluation of the embedding effect in RLSC is conservative, particularly in a short period range. Also, it is observed that the spectrum at the foundation bed of the free field computed by SHAKE is similar to FIM, but the former response is underestimated in specific period ranges. Furthermore, it is shown that presentation of the numerical tables of transfer function of FIM is useful in practical design through comparison ARS of multi-layered soil model with that of equivalent two-layered soil model by RLSC.

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It is well known that the soil-structure interaction affects the seismic behavior of buildings. So it is important to consider the effects in the seismic design of buildings, especially those of low- and medium-rise because their natural frequency is comparatively high. But there is a problem how to estimate the frequency dependent impedance in the time history response analysis. In this paper, the validity of the time history response analysis using the transferred impulse response is confirmed. Then, comparing to the method, the validity and the characteristics of the estimation methods of constant soil springs was studied.

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Base-isolation has begun to be used for buildings which house precision equipment sensitive to micro-vibration disturbances. Since base-isolated buildings may have disadvantage properties from a viewpoint of the disturbances, it is important to estimate the disturbances. This paper describes an estimation method for input loss of ambient ground micro-vibration in the base-isolated buildings which was obtained through analysis of micro-vibration records in 6 base-isolated buildings. This paper also proposes a reduction coefficient for the input loss filter which considers an effect of reduction of the foundation length.

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This paper describes the results of tests aimed at examining the effects of adding vinylon fiber to Liquefied stabilized soil blocks under atmospheric exposure conditions. Tests were carried out on the drying shrinkage properties, resistance to atmospheric exposure, and uniaxial compressive strength. It was found that vinylon fiber reduces the drying shrinkage, crack propagation, and the compressive strength of Liquefied stabilized soil blocks. An appropriate mixing condition was that the clay content of the soil being processed is 30%, cement content is 200kg/m^3, and fiber content is 1.0% of the volume of the soil.

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The values of vertical stiffness of piles using for the monolithic analysis of a building and its foundation to estimate the earthquake-resistant performance are usually lead from load-displacement relationships of static axial compressive or pile-toe load tests. This procedure is not proper for such an extreme short-period load as earthquakes, and it is necessary to exclude creep from the test results. Applied the same method proposed by Tominaga (2004) for lateral load tests, it is found that the average ratio of the value of vertical stiffness excluded creep compared with the value involved creep is approximately 1.92.

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A relationship between foundation damage and superstructure damage done by earthquakes was investigated with numerical simulation. Nonlinear response analyses of the soil-pile-structure system were carried out in consideration of the soil-structure interaction, plasticity of soil, pile and structure, and the liquefaction process for sandy soil. It was confirmed that there are inverse correlations between degrees of foundation damage and degrees of superstructure damage. These correlations were observed during the 1995 Hyogoken-nanbu earthquake.

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Since the method of the rapid plate loading test was introduced into Japan in 1998, it was used as execution management and quality control technique. After that some investigators have made the studies for the test availability, and the authors have also made the rapid loading tests and the static loading tests on sandy soil to investigate the load-settlement relationships and the stress distributions within the soil during the tests. In this paper, it was found out that the rapid loading test results were in good agreement with the static loading test results in the elastic domain of the soil. Furthermore, the stress distributions measured during the rapid loading test were discussed.

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For a steel structural building with long span, for instance supermarkets and warehouses, the method jointing the bottom of steel tube column and the top of the precast reinforced concrete pile and having no spread footing and no tie beam is economical and a reasonable structure. This Paper introduces the jointing method, which was developed by authors, and presents also the results of the laterally loading tests on the joint parts to investigate its structural ability.

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In this report, structural tests of flexible connection of pile head for cast-in-place concrete pile and practical analysis were reported. In this flexible connection, the pile rebars are not anchored to footing and the pile head was formed in the shape of cone or flat to control the rotation. This flexible connection can reduce the stress acting on the pile head compared with regid one. So this flexible connection can realize the high performance of the deformation capacity with little damage of the pile against hard earthquake attacks.

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Using an advanced lattice model (basic lumped mass soil-structure model), in which boundary conditions and modeling methods of a rocking spring are improved, seismic response analyses of a nuclear reactor building, and simulation analyses of a forced vibration test and earthquake records observed at Hamaoka nuclear power plant were conducted. It was shown that the advanced lattice model is an enough applicable seismic response analysis model and approximately expresses real behavior of the nuclear reactor building.

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This paper presents two effective systems for large span cantilever roof, stabilizer and louver system and damping device for cable. At part 1, it was clarified that the stabilizer and louver on the cantilever roof enable to decrease the wind pressure coefficient through wind tunnel tests. The experimental parameters were pitch, angle and distance to grandstand. At part 2, it was clarified that the damping device reduces the vibration of cable to last it through the actual measurement test.

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Recently, in Japan, aseismic retrofit of an existing dwelling house is necessary in a decrease measures of damage such as an epicentral earthquakes to which the future is expected. Therefore, a shaking table tests of dismantled and reconstructed an existing wooden dwelling house was conducted by authors to grasp the seismic performance and collapse process of an existing wooden dwelling house as part of existing house seismic performance improvement study.

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Though there are many researches on steel corrosion, there are few researches on the actual corrosion conditions of steel buildings. This study reports a steel parking building near the coast of Seto Inland Sea, and discusses the influence of fire-resistant materials and the location of members in buildings on progress of corrosion.

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The scheme of analyzing Japanese clay wall is proposed in this paper. The analysis model of a clay wall is composed of frame member for both post and beam, rectangular solid model for clay and contact analysis model for the contact between clay and frame. The smeared crack approach is used for clay solid model as reference. The comparison between tests and analysis shows that the maximum strength, the skelton curve and the curve in unloading of clay wall are calculated approximately.

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In this report, dynamic stability of the frame with CFT columns permitting plastic hinges was investigated. Each story drift angle of the frame were calculated using acceleration response spectrum of ground and the equivalent elastic stiffness which is found from the simplified hysteresis characteristics of each story. We examined a range of the yield column strength ratio and the limit rotation angle of the yield column to secure the stability of the frame. As a result, we got following knowledges. 1) If setting the yield column strength ratio and the limit rotation angle of the columns appropriately according to the class of ground when several columns were yielded, frame dynamic stability in the story can be secured. 2) At the 1st and the 2nd class of ground, the upper limit of yield column strength ratio is proportional to the limit rotation angle of the columns. 3) At the 3rd class of ground, it seems to be better not to make a yield hinges to the columns.

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The purpose of this thesis is to analyze the effectiveness of the slide for the escape at a fire in the residential facilities for the elderly persons. It was confirmed that the method of the staffs taking a slide down the slide together while supporting elderly person's back according to the result of the questionnaire survey and the result of the experiment that descended in the slide for the escape was effective.

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As for the performance related to a fire safety like fire resistance efficiency and evacuation safety, etc., it was confirmed that the priority level was not so high in the condition when purchasing a housing. Moreover, the result that a simple expression of the grade etc. was more useful for the method of expressing the fire safety performance than a probabilistic expression was obtained. The above-mentioned result suggests the necessity for converting the fire risk calculated by an advanced technique into a simple expression.

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Verification method for performance of evacuation safety for converted buildings is presented in this paper. Office property market in Japan experiences liquidity crisis, especially in Tokyo, where completion of a number of huge and high-performance buildings caused the increasing of vacant office space and the decreasing of rental and capital value of old low-performance buildings. Old low-performance buildings have no chance to win the competition in office property market in recent years. Therefore, they have no choice but to be converted themselves from office to other occupancy for survive. In this paper, renovated performance of evacuation safety of converted buildings is analyzed quantitatively, calculating by "Verification method for evacuation safety".

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In an Intensive Care Unit (ICU) of a hospital, L_<Amax,Imin> and L_<Aeq,Imin> were measured. At the same time, the occurrence number of sounds with L_<Amax>≧80 dB were counted, and these sounds were identified. As a result, seventeen types of sounds of L_<Amax>≧80 dB were identified and most of sounds of L_<Amax>≧80 dB were found to originate from the staffs behaviors. Most of the trial improvements were successfully conducted to reduce the number of sounds of L_<Amax>≧80 dB.

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Starting from T-3 rate by using hollow metal door, we performed acoustic test intending to improve the sound transmission loss in low frequency range (125Hz-250Hz). To avoid of resonance in a hollow metal door, we developed new method of door leaf design, named "Oscillo-synthesizing method". Special composition of reinforcement ribs causes considerable sound transmission loss in low frequency range.

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"Guidelines for the evaluation of habitability to building vibration" in AIJ was revised substantially in 2004. Habitability to building vibration induced by human activities is evaluated by maximum amplitudes of 1/3 octave band vibration acceleration on the floor. In order to utilize the new guideline effectively, it is necessary to accumulate the measurements of 1/3 octave band value based on the method for the guideline. WG on measurement technique of environmental vibration in AIJ implemented an experimental measurement of floor vibration caused by human activities. Results were the following. 1) It is preferable that the habitability is evaluated by each maximum of vibration acceleration amplitudes in 1/3 octave band during the period of measurement. If unable to measure the amplitudes, it is possible to use running root-mean-square values (integration time of 0.01 s). 2) We applied "Guidelines for the evaluation of habitability to building vibration" (AIJ, 2004) to the measurements and considereda usage notes.

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National wide inquiry was carried out in order to obtain actual state concerning lighting of living room. The results of the inquiry are shown as follows. 1) As for the lighting of the living room, the majority of respondent used one kind of light for one living room. 2) The lighting of the living room is hardly changing for ten years. 3) In the daytime, lighting rates increase. 4) The consciousness has not been brought up that they change lighting to be suitable for their behavior.

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In order to reduce heat island effects in cities, this paper presents experimental measurements of absorption characteristics of solar energy on spray painted rough surfaces, ceramic wall tiles, colored plastic sheet, concrete, asphalt, stone and brick. It is found that the solar energy absorption characteristics are well correlated by the brightness index of the surfaces. And the solar energy absorption decreases with increase of surface brightness indices of the materials.

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The purpose of this report is to consider the results of a survey on detached houses with "the glass-covered space" in Hokkaido and the results of the questionnaire on the sunroom's thermal environment in the Pacific coast region of East Hokkaido, where in summer, people have dense fog while in winter they enjoy abundant sunshine. It was found through the survey that many houses in Hokkaido have the glass-covered space at the entrance just before the front door. The sunroom was found most popular in towns of the coast rather than those of the inland. The sunroom gives most of the people on the coast much satisfaction.

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