This paper deals with three series of experiments for clarifying the general tendencies in carbonation of concrete masonry of which units are produced by vibrio-pressing methods, and a proposal on the methods for predicting carbonation depth in building components made of grouted concrete masonry. Various grades in characterized compressive strength of concrete masonry units were experimented to clarify tendencies in the carbonation processes under an accelerated condition in order to propose the both equations for predicting carbonation coefficient of concrete masonry units and carbonation processes in grouts through faceshells of these units.

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A The maturity method in which the strength gain of cement concrete is expressed as a function of the integral of the curing period and temperature of the concrete has often been applied to its strength prediction. For the purpose of the application of the maturity method to the compressive strength prediction of lightweight polyester mortars using an unsaturated polyester resin as a binder, the lightweight polyester mortars with various catalyst and accelerator contents, which affect their working life and strength, are prepared, tested for compressive strength, and the datum temperatures of the maturity equations are predicted.

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This paper proposes a non-destructive testing method of moisture content in hardened concrete by the electric prperties of a ceramic sensor embedded in concrete. In general, the clayburned porous ceramics has a superior water absorption and discharge capability, and it is electrical insulative in a drying state, but it is highly conductive and has electrostatic capacitance in a wetting state. The proposed method can utilize those characters to estimate moisture content in concrete. This paper deals with manufacturing method of the sensor, measuring conditions, influencing factors on the relationships between the moisture content and the electric resistance or electrostatic capacity and the measuring accuracy. The proposed method, however, requires the revision of electric resistance and electrostatic capacity by the ambient temperature, and the calibration curve by water content per unit volume of concrete. This paper, finally, illustrates the deviation of measured moisture content of the hardened concrete.

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The writer is struggling to develop a robot for work on an outer wall which can detect detachment without staging in order to save labor and to improve safety for detachment detection and their repair work. Then, the writer reports in this paper mainly 1.Confirmation of the mechanism to move the robot on a wall. 2.Experiments on the valve mechanism of the shape and suction of small sucker discs. 3.Detachment detection experiments using a sound wave sensor on an imitated tile wall.

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This paper presents the evaluation index of pitch of wash and slipperiness on bathroom floors from a viewpoint of safety of the aged. At first, we carried out the sensory test using sample floors and young panels wearing an outfitting equipment. The equipment was developed for the young to simulate geriatric gait. After the sensory test, we constructed the psychological scale. Then, we measured C.S.R-B of the sample floors using O-Y-Pull Slip Meter. C.S.R-B was the quantitative value corresponding to slipperiness. Secondly, based on the relationship between the psychological scale and pitch and C.S.R-B, the evaluation index was obtained.

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Seismic design load for elasto-plastic structures is reduced according to the permissible ductility, in that method there are two well-known theories, i.e., displacement conservation theory and energy conservation theory. However, these theories are contradictory and they give different values for the reduction factor. This study shows that the two theories are not opposed when taking into consideration the fact that the cycle number of plastic excursions is inversely proportional to the yield strength. From this observation it is derived that the energy input rate is proportional to the yield strength, and thus the spectrum of energy input rate calculated for a particular yield strength can be easily adjusted to other systems having different yield strengths. It is also found that spectrum values of energy input rate for near-field earthquakes are larger than those of oceanic type earthquakes because of the difference in hysteretic cycles.

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The purpose of this paper is to present a simple and reliable method to represent frequency-dependent mechanical properties of a linear visco-elastic damper by generalized Maxwell model or Voigt model. The paper first deals with an experiment of random loading to a damper. Then, the Fourier Transform to both input displacement and output load is performed for complex modulus and complex compliance, from which equivalent stiffness and equivalent damping coefficient of the damper are obtained. Finally, the accuracy of the method is confirmed by comparing experimental and analytical hysteresis loops of the damper subjected to a random displacement simulating the one expected during an intense earthquake.

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A large-scale dynamic test facility like a shaking table naturally has the potential to disturb its surroundings with unwanted vibration. To prevent this, the authors developed a vibration isolation system with air springs, applied it to the basement of the shaking table installed at Kajima Technical Research Institute, and obtained the anticipated results. After that, Japan Highway renewed its traffic simulator machine and, taking this opportunity, decided to install the vibration isolation system. This report presents a series of results from the design stage to performance verification testing. At the first stage, the response of the surrounding soil surface and the basement of the test facility building were measured before the renewal and the design target level of response reduction was determined. Secondly, a loading test of the air spring itself was conducted and the design specification was revised. Finally, a performance verification test was conducted on the test facility after the renewal. The test results indicate that the response of the soil surface at the site border to test machine operation was reduced to the micro tremor level.

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An earthquake early warning system has been developed to obtain real-time profile of impending ground motion in order to minimize earthquake hazard The system is designed to analyze the P-wave portion of earthquake signal and instantaneously evaluate earthquake parameters such as magnitude, epicentral distance and focal depth. Neural networks are employed to add self-learning functions to the existing system and to reduce the error of estimation for site-specific applications. The neural network has been successfully trained with recorded data to produce accurate and informative earthquake parameters.

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A series of laboratory tests were performed on high-quality undisturbed samples of a gravelly fill made of weathered granite (locally called Masado) in order to investigate its physical and mechanical properties. The following were concluded. 1) Considering the result that the Masado fill was liquefied during the 1995 Hyogo-ken Nanbu earthquake in spite of its large particle size, some of the design codes including the methods for evaluating the liquefaction potential is hoped to be reviewed. 2) The internal friction angle ( φ_σ) of Masado fill ranges between 39.5 and 41.8 degrees, these values are relatively large compared with that of other Holocene and Pleistocene gravels having higher N i values. 3) The permeability coefficient of Masado fill ranges between 2 × 10^<-5> and 10^<-2> cm/sec, these values are almost the same as those for sandy soils. So it is reasonable to investigate the cyclic shear strength of Masado fill under undrained condition. 4) The liquefaction strength (R: cyclic stress ratio to cause DA=5% in 15 cycles) is only 0.15 to 0.23, this value is nearly equal to that of Toyoura sand with 70 % of relative density. The relationship between R and Ni value agrees well with the empirical correlation proposed by Yoshimi et al for sandy soils.

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The effect of strain rate to a stress-strain relationship is examined based on dynamic tests to propose a new dynamic skeleton curve for reinforced concrete shear walls in a reactor building. Such effect was not taken into consideration though quite a few proposals of the relationships, i.e. shear stress-strain and bending moment-curvature, were made in the past based on extensive static loading tests. The proposed new dynamic skeleton curve is used in a non-linear seismic analysis with a lumped mass model for the reactor building.

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This paper is concerned with three-dimensional finite deformation analysis of a closed circular cylindrical shell subjected to pure bending. It is expected in this case that the element of the cylindrical shell will be deformed approximately to the torus shape. Then, in this paper, the torus coordinates are employed to indicate the deformed state of the shell. This approach using the torus coordinates makes the analysis simple. This paper also investigates whether the shell collapses by the Brazier budding or by the plastic yielding due to local stresses. It is shown that the Brazier buckling occurs only for a very thin shell. The collapse of the moderate or thick shell is followed by the plastic yielding. This indicates the importance of investigating the local stress as well as the Brazier buckling.

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In the former study on the numerical simulation for the partial beam with the ball-joint connection, the ability of the numerical modeling was proven by the present authors. By using the similar method, the estimative ability of the present simulation method for the practical latticed dome is investigated through comparative analyses between numerical analyses and experiments. The numerical analyses are executed with parameters, looseness, initial compressive force at the connectors and initial deflection at noticeable node of the dome. Through comparison between the experiments and the numerical simulations, the structural behaviours of the tested steel single layered latticed domes with ball-joint connections are also precisely discussed

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Folding structures can be a smart solution for effective transportation economizing space and for quick assemblage saving time and labor at construction sites. In the paper a numerical procedure to find one of the optimum paths to fold structures into desired configuration is proposed. Concepts of the minimum displacement path and the geometrical measurer are introduced in order to assess the validity of computed folding paths. The definition of the bifurcation point on a folding path and bifurcation point is discussed. Two illustrative examples are presented and how to compare the effectiveness of paths among different folding paths is demonstrated. Classification of bifurcation paths at a bifurcation point is attempted with the aid of group theoretic approach.

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This paper has described various kinds of tests on the steel connectors embedded into the timber with adhesive. These connectors are threaded steel rods with a hole at center of each rod to transport the adhesive to the end of the rods. Tension test, bending test and shearing test for beam-column connection were carried out. From this test result, the fundamental data for the structural design of timber structures were obtained. The assembly at connection and reasonable structural design can be carried out easily by using this new connection system.

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This paper presents the behavior of a three dimensional RC structure under bi-axial loading. The behavior is investigated in two ways: one is by experiment conducted on a test model composed of a joint with a column and two beams extending orthogonally, and the other by nonlinear finite element analysis. Good agreement was observed between the results from the analysis and those from experiments. A strut is formed from one upper side to the diagonally opposite lower side when a load is applied to both ends of one beam in opposite directions. When, by holding the tip deflections, a load is applied on the other beam in the same manner, the strut undergoes a transition and ultimately runs from one upper corner to the diagonally opposite lower corner.

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The present paper discusses structural characteristics of the tubular steel trussed tower with gusset plate typed connections, specially having an eccentric joint applied to the crossing between column and braced members. Firstly, it is clarified effects of eccentric bending moment to the column buckling strength by horizontal loading tests and non-linear analyses for the model planned to make its column member buckle at first. Secondary, it is discussed effects of local deformation of the column tube at the eccentric joint to static and fatigue bearing strength of its connection. Lastly, based on results of the present study, it has been authorized fundamental data for the practical design in case of application of the eccentric joint to such the steel tower.

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This paper presents the results of earthquake response analysis of the beam fractured steel building structure that suffered from the 1995 Hyogoken-Nanbu earthquake. In order to estimate the earthquake input energy and inelastic behavior of fractured beam end, the comparison of analytical predicted and observed damage was carried out. From the results of the analysis, it was presumed that the hysteresis energy input (VD) in this building was more than 300 cm/sec.. And effect of energy absorption of joint panels on reduction of beam damage was also discussed in this paper.

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Little attention has been given to the study that many materials which have different properties have been dealt with. In this paper, materials have been widely selected. Many figures of correlation between many material properties have been shown. The relative relation of selected material has been understood by investigation for these figures. A constitutive equation that can represent hysteretic stress-strain relation has been proposed. The equation has been considered with the material property. The following observation has been obtained. A material index, Semi-Complimental-Energy ratio (S.C.E./ay), is very effective to understand characteristic of material under monotonic or cyclic loading.

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Scallops of the beam-web at welded beam-to-column connections of steel frames bring partial loss of cross sections at the part subjected to large bending moments when a severe earthquake occurs. Therefore, they are not desirable from the point of view of mechanical behavior. This paper presents the bending tests performed using specimens of beam-to-column joints on shop assembling carried out to investigate the effect of non-scallop methods and beam-scallops on fracture behavior, ultimate strength and deformation capacity of the steel beam-ends. It is concluded that a beam without scallops has earlier brittle fracture and higher strength, and larger deformation capacity than a conventional beam with scallops. Finally, it recommends the details of the end of the beam of the non- scallop method of construction with the cost performance being based from the view point of the design, the building.

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Some composite beam problem requires the different boundary conditions in each beam. The degree of freedom in each node becomes three by permitting split-off action, and it becomes possible to treat the boundary conditions independently for the each beam terminal. The author develops new composite beam theory permitted this action and shows the effectivity of this theory by applying it to the problem of the composite floor slab smeared with the flexural cracks in the tension zone of the concrete portion. The solution of this illustrative problem also gives the explanation of the phenomenon of the observed poor composite action when we use some group of steel deck plates.

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A lot of study has been executed on the ultimate strength of concrete filled steel tubular columns (CFT). Especially, the confined effect to the filled concrete by the steel tube has been the main subject in these studies. However, in case of the CFT in which high strength materials are used, the contribution of the confinement effect to the ultimate strength has not yet been clarified. Therefore, we did the stub column tests on concrete filled steel tubular short columns which have steel tensile strengths of 400-780MPa and concrete compressive strengths of 20-90MPa. The relationships of failure pattern, deformation capacity and ultimate strength are discussed in this paper based on test results.

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Heat flux distribution to the steel beam supporting a ceiling exposed to an isolated fire source on the floor has been modeled by experiments using propane porous burners. Test conditions were chosen to cover the range in which the benefit of the "localized-source" assumption be the most significant. Heat flux on the upper and lower flange and the web are correlated against the flame length , which is further correlated against the ceiling-beam-fire geometry and the size and intensity of the fire source. The experiments demonstrate that temperature at the stagnation point of the beam in this configuration is reduced significantly than uniformly heated surface due to the high conductivity of the steel.

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Tensile stresses in the tension legs attached to a large floating island are evaluated for wind waves and seaquakes by a wet mode superposition approach and random vibration theory. The conditional failure probabilities of tension legs are calculated by solving a first passage problem for different load intensities of each loading. Then, unconditional failure probabilities of both loadings are separately calculated by multiplying the conditional failure probabilities by the corresponding occurrence rates and integrating them with respect to all possible load intensities. The minimum required stiffness of tension legs is determined in such a way that the summation of lifetime failure probabilities of both loadings becomes less than a target failure probability. Numerical examples are presented to illustrate how to determine the minimum required stiffness of tension legs at different offshore sites.

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This paper contains some contradictory descriptions to those in my early papers2)>3). Therefore the following questionnaires are raised; 1) Why should the estimation period be ten minutes. 2) How can it be checked that the internal pressure of the instrument screen corresponds to the atmospheric static pressure. 3) Why does the coefficient of the internal pressure converge more easily in the lower wind speed conditions. 4) What do you think about the difference between an actual wind flow field and that in a wind tunnel.

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The author thanks Dr. Junji Katsura for his questions, and he answers as follows; Firstly, the authors made clear that their point of view on the method for evaluating fluctuating wind pressure was different from Dr. Katsura's. Secondly, we replied to comments made by Dr. Katsura 1)The time period of ten minuets for evaluating wind fluctuation was chosen to correspond to the weather data measured by the meteoro- logical agency. 2)The method of measuring atmospheric static pressure was determined by taking into account the technical problem with the reference static pressure box and the limited extent of the owner's cooperation. 3)There was not a significant difference in term of coefficient of variation for the mean wind-induced internal pressures between the low and high wind velocities though a dispersion in mean wind-induced internal pressures was found in the high wind velocities. 4)It was thought to be sufficient that results of wind tunnel tests correspond to the average statistic value derived from fluctuating wind pressure. It is impossible to model every detail of full-scale conditions in a wind tunnel test.

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