The electronic devices using electromagnetic wave increases recently. It has been important to study the electromagnetic compatibility inside building space. In this paper, the recycling board using waste plastics and paper is developed and added electromagnetic wave absorption characteristic mixed with ferrite and carbon. The better mix proportion of absorption is examined with parallel wire line method by small-size specimen. Large-size recycling board with electromagnetic wave absorption is made and has rather than 10dB absorption characteristic of electromagnetic field strength in quasi microwave band. This board will be able to improve the complex condition in electromagnetic environment.

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It is well known that the long-term strength of high strength concrete in structure subject to high temperature history at early age is lower than that of standard cured specimens. Nevertheless, simple methods of estimating the strength of concrete in such structure have not been established yet. In this paper, a simple method for estimating the compressive strength of concrete in structure subject to high temperature history at early age using the compressive strength of standard cured specimen was investigated. Through this investigation, a strength development model relating the compressive strength to the logarithmic aging time has been suggested. The kind of binder, maximum temperature, and the water-binder ratio has been taken into consideration as the parameters that influence strength development. The results obtained through this method were compared and found to be similar to about 200 site experiment data, indicating that the method is of practical use.

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Thermogravimetric analysis (TGA) of cement mortar substrates was conducted after the accelerated carbonation test of the cement mortar specimens with the finishing materials in order to evaluate the protective performance of various types of finishing materials against carbonation. Quantitative analysis of calcium carbonate in cement mortar substrates was carried out in the depth direction from the surfaces of the specimens by TGA. The phenolphthalein method was also applied for determining neutralization depth of the specimens. The main results obtained can be summarized as follows: 1) Protective performance of various types of finishing materials against carbonation could be evaluated and compared by the TGA method and the phenolphthalein method. 2) It is well known that the parabolic law can be obtained between carbonation periods and neutralization depth values determined by the phenolphthalein method. It was confirmed that such parabolic, law was also obtained between carbonation periods and the total amounts of calcium carbonate formed in the specimens in this study. The coefficients obtained from the both parabolic relations were reasonably correspondent to each other.

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This paper discusses a vibration control performance of damping devices installed in a building structure. The motivation of this study comes from the recognition that we often observe much smaller damping performance than is expected from the pre-analytical study in many application projects. Emphasis is placed on the stiffness increase of the structure that is equipped with those damping devices. The relationship between the damping and stiffness augmentation is analytically obtained and expressed in a closed form solution. Therefore, the performance in terms of damping factor is easily evaluated by means of real eigen-value analysis. Numerical simulation is also conducted to ascertain the validity of the proposed method for a relatively large structure under earthquake disturbances.

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System identification method proposed by the authors to estimate the dynamic characteristics of a building itself, under an imaginary fixed base condition in the other words, is studied for buildings with large soil-structure interaction(SSI) effect. The applicability of the method to buildings with embedment is studied in this paper. The assumed system model for the method is slightly different from the actual SSI system. This difference as well as the additional input to the underground wall may produce some system identification error. For these reasons, the proposed method and other spectral analysis procedures as well as the ARX method are applied to the response of an analytical model and results are compared. The benefit of the use of such model response instead of actual measured data is that the causality is very clear. In result, relative merits and demerits of the methods, cause and mechanism of them become clear. Furthermore, the applicability of the proposed method is confirmed. Such a method can be used to check the change of dynamic characteristics of the buildings after large earthquakes or long - term service.

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In this study, the formerly developed Adaptively Shifted Integration (ASI) technique for the linear Timoshenko beam element is modified into the ASI-Gauss technique by placing the numerical integration points of the two consecutive elements forming an elastically deformed member in such a way that stresses and strains are evaluated at the Gaussian integration points of the two-element member. On comparison with the ASI technique, the ASI-Gauss technique proves its higher accuracy and efficiency in elastic range. Instead of applying impact loads in the form of nodal forces, this study simulates the impact phenomenon by means of contacts between the elements involved and the elemental contact algorithm is verified from the point of conservation of energy. A structural collapse analysis of a steel framed structure due to collision with a small aircraft is performed by considering member fracture. From the results obtained, we can observe propagation phenomena of impact loads and shock waves. Moreover, a considerable difference of the impact damage on the structure is observed when the cruise speed of the aircraft is changed.

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Two-way cyclic lateral loading tests are performed at alluvial soft deposits to evaluate the behavior of piled raft foundations, which have rigid joint or pin joint at pile heads. Each foundation consists of a 2.0m wide by 1.5m long concrete block with 20 kN/m^2 loadings, and two steel pipe piles (pile spacing to diameter ratio = 10) arranged in a line. The displacement and stress of these foundations are compared to those of a single pile tested at the same site. The results show that the piled raft with the pin joint at pile head is specifically effective foundation.

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The previous thesis (Part 4) presented cross-sectional stress interaction between H-steel pillars in soil cement earth retaining wall and composite wall (H-steel with RC basement wall), during the course of Sakauchi construction. In this study, the author works out a similar theoretical analysis to RC earth retaining wall, associated with RC basement wall to be constructed successively. The study proved that (a) the cross-sectional stress distribution of reinforcing bars in composite wall becomes discontinuous across the boundary of earth retaining wall to basement wall, and (b) the stress in the earth retaining wall part will.differ greatly from the value as calculated ignoring the basement wall.

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Properties of membrane materials have material nonlinearity and stress relaxation, due to slackness and crimp interchange of yarns and viscoelastic characteristic of coating material. The stability of .tension membrane structures depends on existing prestress in the membrane. Therefore, the stress relaxation is an extremely essential problem for this structure. For the maintenance of the reliable structural efficiency, it is necessary to investigate the membrane behavior under construction and the stress relaxation, and to establish the relaxation analysis. This paper presents the membrane material experiments, which perform to grasp material characteristics under relaxation, and a stress-strain model for the relaxation analysis.

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Seismic responses of lattice domes with substructures are known to be very complicate, because of the dome having large numbers of parallel vibration modes, and their amplitude changing drastically along the relationship between domes and substructures. Under limited condition, however, their response characteristics are considered to become relatively simple. In this paper, various shapes of domes are analyzed using response spectrum analyses with CQC method, which is less time-consuming than time-history analyses. The conditions for simplifying the principal modes are made clear through these studies, and their response characteristics are discussed.

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This paper attempts to build the parameters of hysterisis models for resisting shear walls of timber structures. These parameters enables engineers to make models easily by summation of the parameters. In order to establish these parameters, this paper focuses on the following three subjects. First : Proposition of a hysterisis model fit for timber structures. Second : Proposition of parameters of the resisting shear walls, based on about 100 tests. Third : Prediction of shaking table tests from the models of summation of the walls. In the first part, the combination model of bilinear model and slip model is adopted for its simple mechanism. In the second part, the database serves for determining parameters of five different types of walls. In the third part, three models of one full-scale wooden house are proposed. The earthquake responses obtained by the models correspond to the shaking table tests, and this result confirms the accuracy of the parameters.

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This paper introduces the experimental and analytical results obtained by the shaking table test and its analysis of a three-storied steel frame with HPFRCC response control elements (HPFRCC elements). Objectives of this study are to confirm the remarkable effects in structural control by the HPFRCC elements experimentally, and to verify the analytical model. The seismic response deflection of a frame with the HPFRCC elements was much smaller than that of a frame without the HPFRCC elements. In addition, it was observed that the boundary frame confines the vertical elongation caused by HPFRCC elements' rotation, therefore very high axial force worked on the HPFRCC response control elements. Axial force working on the HPFRCC elements was the same as that predicted by the method of proposed by the previous study. The response deflection calculated by the time history response analysis was well correspondent with the value obtained by the shaking table test.

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In this paper, the behaviour on tapered joint panels in RHS column to beam connection is investigated. A series of tests are carried out to investigate the elastic plastic behaviour on tapered joint panels using connection subassembrages subjected to static cyclic lateral load corresponding to seismic loads. The variables of the tests are as follows: (1) configurations of the joint panel, (2) difference between upper column width and lower one, (3) magnitude of axial force in column. Also numerical calculations using elastic plastic finite element method are performed to examine the stress and strain distribution in elastic plastic region. The following results are concluded: 1) The elastic shear rigidity of tapered joint panel is larger than that of non-tapered joint panel which has the same width of upper column in the tapered joint panel, and smaller than that of non-tapered joint panel which has the same width of lower column in the tapered joint panel. 2) The yield shear strength of the tapered joint panels is determined by the upper panel area independent of the difference in width of upper panel and lower panel.

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In this paper, effects of floor slabs on ultimate earthquake resistance of steel moment frames are investigated. Earthquake response analyses of multi-story steel frames are carried out, and ultimate energy absorption is derived from the results by consulting practical ductility capacity of composite beams. In the analyses, inelastic behaviour of composite beams is considered. And ductility capacity of the beams, which defines ultimate state of the models, is defined considering the effects of floor but they are not important in earthquake resistance of the structures, except the effect on ductility capacity of beams. And the effect of floor slabs on ductility capacity has serious influence on ultimate earthquake resistance of steel moment frames, especially when its joint efficiency is poor.

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This paper presents a method to evaluate the ultimate strength and fracture mechanism of inclined fillet welds under different loading angle. The proposed mechanical model consists of two rigid parts of the fillet welds separated by a fracture plane, and the ultimate strength and the fracture mechanism of this model are derived by means of the upper bound theory. Based on the theoretical solutions, a simple design formula is presented. Its accuracy is verified by the results obtained from loading tests conducted in this study.

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The dynamic loading test was conducted using the bolted frictional slippage connection specimens that sandwiched copper alloy sliding plates in order to investigate frictional slipping behavior such as the variation of slip coefficient while slipping and the influence of the initial bolt tension to the kinetic slip coefficient. As the result, specimens using brass sliding plates showed stable enough frictional slipping behavior rather than other sliding plates and negative correlation between kinetic slip coefficient and initial bolt tension. In this paper, in order to predict the slip coefficient of the brass-using specimen, Chapman's nonlinear regression equation was used and its regression coefficients were obtained using nonlinear least squares fitting. This equitation predicted varying slip coefficient of specimens approximately.

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An optimum design approach for a group of buildings is proposed. Any two buildings closely situated may result in serious damages simultaneously by a natural disaster because of its spatiality. Due to this, it is important in optimum design of a group of buildings to treat suitably the correlation of loads caused by natural disasters. So far, it seems that expected total cost is of main concern, but the spatial correlation of loads can be dealt only with more than the second moment of total cost or even distribution function of total cost. Also important is the situation with which owner faces and his/her attitude toward building risk. The consequences of damages of a group of buildings caused by natural disaster may be much more serious than just the summation of each individual building. These affairs should be properly considered in design of a group of building. In this paper, we propose one rational approach, and its characteristics and consistency are confirmed through three simple but illustrative examples.

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