Sensory tests were done on the perception of staining of walls of existing buildings having various wall finishes. The evaluation values for staining obtained were then examined as for their relationship with measured values of several visual features of finishing materials and coatings of the same kinds that were used on the walls of tested buildings. The visual features of the finishes which had the most significant effect in determining the evaluation of staining were; density of texture with stone finishes, color and density of texture with ceramic tile finishes, and variation in luminance with coated finishes, metal finishes, and exposed concrete finishes. Equations which could be used to predict the perception of staining of external walls from the visual features of each wall finishes are given.

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This paper presents the influence of material and mix proportion on the slump flow time of high-fluidity concrete with a slump flow of 65±5cm. The viscosity of high-fluidity concrete was evaluated by the slump flow time, and the viscosity of matrix mortal and cement paste was evaluated by the time of flow on the funnel test. In this study, in the case of high-fluidity concrete which have low yielding value, the relationship which is formed among the slump flow time and the time of flow is almost linear. The result that the slump flow time of high-fluidity concrete could be estimated with functions of factor of mix proportion was obtained.

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This paper deals with autogenouse shrinkage stress of reinforced ultra high-strength concrete column. Two full scale reinforced concrete columns were constructed ; one was constructed in summer and the other was constructed in winter. The influence of heat of hydration on the autogenouse shrinkage stresses of these columns was investigated experimentally. In addition, Young's modulus and creep of concrete at early ages were tested. As the result, the magnitude of autogenouse shrinkage stress in summer was higher than that in winter. On the other hands, Young's modulus of concrete in summer developed more rapidly than that in winter. It was found that heat of hydration strongly affected the autogenouse shrinkage stress of concrete. Based on the Young's modulus and creep of concrete at early ages, a step-by-step method could predict the autogenouse shrinkage stresses of these columns.

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This paper introduces a basic methodology for designing building construction robots based on the robot modularization technology. In the paper, four issues are discussed; 1) a procedure to design modularized building construction robots 2) description of operational functions and conditions with work modules 3) tablating substitute of arm and wrist modules, and 4) design of robot configulations and mechanisms for automating interior finishing work.

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This paper presents the evaluation method on slipperiness of mats on the floor, which is important performance ensuring safety of dwelling. First, we carried out sensory tests, and made sensory and evaluation scales of slipperiness of mats on the floor. Then, we clarified the tendency of loads on floors affected by feet through mats. Next, we established measuring method of the slip resistance composed of C.S.R (formerly presented as the slip resistance of floors) and L(moving distance of mats) to correspond sensory and evaluation scales. As a result, we presented the evaluation method dealing with the measuring method and evaluation indices of slip resistances.

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It is generally thought that the vortices shed from a three-dimensional square prism on a ground plane become to have a three-dimensional structure because of the free end. These vortices differ from those in case of a two-dimensional prism, and these are known to evolve into Karman type or Arch type behind a three-dimensional prism according to the aspect ratio of the prism or the Reynolds numbers. These phenomena are highly affected by the downwash over the free end. Here, we numerically simulate the flows around a three-dimensional square prism on a ground plate by use of the interpolation method. First, we estimate the accuracy for the prediction of the flows through the comparison with the previous experimental data. Second, the local aerodynamic characteristics determined by these vortex structures are discussed.

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First, we surveyed the actual condition of living difficulties the people were suffering because of the water supply suspension after the Hyogoken-nanbu earthquake, and extracted the two main measurable factors of daily life difficulty, that is, lack of supplied water and fatigue from water carriage. On the basis of these factors, the formula for quantitative evaluation of daily life difficulty from water supply suspension was proposed. Secondly, using this evaluation formula, we calculated the daily life difficulty in Kobe City after the earthquake. And we also calculated the difficulty anticipated under the plan for emergency water supply that had been worked out by Kobe City authorities following the earthquake. In conclusion, the authors showed the necessity of speedy restoration of complete water supply, and the importance of upgrading the restoration ratio to reduce the inconvenience of daily living in the whole stricken area.

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The artificial neural network is a newly developed technique for the identification and modeling of linear and nonlinear dynamic systems through the use of measured experimental data. In this paper, a neural network approach for the structural dynamic response prediction is presented and applied to an elastic and perfectly elasto-plastic system with a single degree of freedom. A three-layer backpropagation neural network is chosen as the neural network to predict the response at the next time step as an output with the input earthquake records and the corresponding responses at the past few time steps as inputs to the neural network. The application examples show the great promise of using the neural network in structural dynamic response prediction.

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Active structural-control is a new technology of earthquake resistance strategy for civil structures. This technology, however, is currently under way of development, having some issues to be solved. One of the most significant issues is how to control buildings regardless of earthquake severeness. This paper presents variable gain-based structural control accounting for AMD stroke limitation. The control algorithm is based on the philosophy of Maximal admissible set of initial state, which was originally proposed for a system with no input excitation. Simulated and experimental results demonstrates how effectively and satisfactorily the presented methodology works.

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The experimental device to increase the accuracy of passive earth pressure measurement was developed, and the passive earth pressure test of the wall translating was performed. The followings are the results obtained through the test. (1) The moving wall friction angle δ_c, when the total horizontal earth pressure is at its maximum, is 0.59δ_1 in dense sand and 0.71δ_1 in loose sand (δ_1: the friction angle between sand and wall) (2) In both dense and loose sand, the horizontal earth pressure increases in proportion to the depth while the wall friction distribution shows the shape of a parabola.

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Space structures should be designed in such ways that they resist against external design loads including their own weights mainly by their definitely strong capability through membrane stress resultants. Up to now, there have been several attempts to create the bending free shapes which enable us to realize rational shapes for space structures and shells both experimentally and theoretically such as the works by H. Isler, N. F. Ortega and our previous researches as well. Present paper deals with minimization process by which bending free surface for space structures can be directly obtained through application of the nonlinear programming technique for the objective function which is composed of bending moment components. Grid shell and latice dome are shown as numerical examples of space frame structures, where effectiveness and usefulness of present treatment are clearly appealed and some investigations on the mechanism through which bending free structures are created and which is peculiar to frame-type structures are also discussed.

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Collecting available 332 test data, the database of interior beam -column joints was constructed. In this paper, analyzing the previous test specimens, which were failed in joint shear before beam hinging, the joint shear strength was examined. Following findings were obtained : (1) Joint shear strength was greatly influenced by concrete ,strength [σ_B]. However, axial column compressive stress level and joint shear reinforcement ratio were not major factors for joint shear strength. (2) Joint shear strength [_cτ_p] was evaluated to be proportional to σ_B^<0.712>^. (3) Specimen size and shape does not affect significantly on joint shear strength. (4) Shear failure in joint before beam hinging can be classified by the ratio of joint shear strength to the joint shear stress at beam flexural capacity [_cτ_p/τ_u] .

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This paper aims to make clear "Arch mechanism" in R/C column, subjected to compression and shear-bending, experimentally. Specimens have no shear reinforcements and their longitudinal bars, PC bars, are covered with paraffin wax. By the results of tests, it was known that the ultimate shear strength is influenced by relation between "shear crack strength" and "Arch strength". This paper shows how to calculate "shear crack strength", and presents the shear strength of R/C column by decreasing "Arch strength" to the type of column whose "shear crack strength" is below "Arch strength". With this method, the shear strength of "Arch mechanism" in R/C column can be estimated sufficiently.

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Array measurements of microtremors were performed at six sites in the Sendai region. Using the microtremors we calculate phase velocities of Rayleigh wave by F-K spectral analysis in the frequency range from 0.5 to 3.0 Hz. Then we invert S-wave velocity structures from the seismological bedrock to the engineering bedrock by fixing the surface ground structures which are already known. As a result, well-controlled thicknesses of two layers are obtained at four sites. The thicknesses at the other two sites are estimated by using the microtremors together with the site responses derived from strong motion records.

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Vibration controlled structures using energy absorption dampers have become popular recently. The low and high cycle fatigue properties of hysteresis dampers in these structures are important. We carried out fatigue tests on axial-yield type hysteresis dampers made of steel at certain strain levels. The key findings regarding design are as follows, 1) The fatigue design of the dampers in the elastic range can be based on an ordinary connection design formula. 2) If the strain range, Δεt, occurring at a large earthquake is less than 1.5 %, the performance of the dampers is good. 3) By using plastic range positively in case of a strong wind load, the design criteria of the dampers for earthquake and strong wind have more flexibility.

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The formulas, reflecting the characteristic of failure modes, about the ultimate strength of self drilling tapping screw connections fastening two thin steel plates, are presented in this paper. The theoretical investigation on the transfer mechanism of forces makes clear the characteristics of each failure mode. And also, it derives the relations between the ultimate strength and the factors by which it is governed. The value of unknown parameters for establishing the efficient formulas of each failure mode are decided from the data of experiments which examined 124 specimens. Moreover, the availability of these presented formulas is confirmed by the results of another experiments quoted from the reference.

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This paper describes the effects of material properties on the local buckling strength and deformation capacity of H-section stub-columns. The local buckling and the post local buckling behavior of H-section stub-columns are analyzed by the plastic hinge line analysis. The analytical variables are the width-thickness ratios of component plates and the material properties, such as tensile strength, strain at initial strain hardening and strain hardeninhg modulus. In this study, a modified complementary energy is proposed as an important parameter on the energy absorption capacity of the structural member. From the analytical results, the local buckling strength and the deformation capacity of the stub-column are influenced by the modified complementary energy index. In order to evaluate the deformation capacity of structural member, the material properties of the plastic range, such as a modified complementary energy, should be considered.

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Through-gusset connection is often used for axially compressed tube member. Buckling modes are the bending of whole member and the bending in the region of the connection. Mechanical model corresponding to each buckling mode is established. Using these models, elastic buckling loads are analytically derived. The buckling behavior is examined for the members having a variety of proportion. It is obtained that the member having long connection-region buckles in the connection-region and the corresponding buckling load can be smaller than the Euler's load of the pin-ended tube. The analytical results are confirmed in comparison with the results of loading tests.

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The resistance of a structure against an earthquake is related to its ability to absorb the seismic input energy. The development of devices for dissipating the seismically induced energy on the structure is a subject that is receiving large attention in the field of earthquake engineering. One example of these devices is the steel plate with slits. In this paper, the ultimate energy absorption capacity of slit plates subjected to shearing deformations is investigated experimentally. The parameters involved on the tests are the aspect ratio of the struts that form the plate (B/H), the material (mild steel, high strength steel) and the loading pattern. The hysteretic curves are decomposed into the skeleton part and the Bauschinger part. The ultimate energy absorption capacity is the sum of the energy dissipated on the skeleton and that on the Bauschinger part. As a result, it is shown that the energy attained by the skeleton part can be analytically predicted and that attained by the Bauschinger part can be estimated empirically.

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In AIJ (Architectural Institute of Japan) design formula for slender steel-concrete composite columns, modified method of the superposed strength of a column section is adopted by considering the effect of additional bending moment (Pδ moment). We have proposed an equation for evaluating the strength of slender concrete columns, and using this we showed that the strength of concrete filled steel tubular (CFT) columns are well predicted. In this paper, with respect to the strength of RC columns, end moment (Mu)-axial force(Nu) interaction relations are calculated by assuming a sine curve deflected shape of the beam-column. As the analytical parameters, buckling length-section depth ratio, tensile reinforcement ratio and strength of concrete are selected. On the basis of the analytical results, the superposed strength is examined, and proposed.

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In AIJ design formula for composite steel tube and concrete structures, the limiting width (diameter)-to-thickness ratio of steel tube is relieved to 1.5 times that for a hollow tube. In this paper, it is investigated whether the limiting value for concrete-encased type section is appropriate or not. As the experimental parameters, shape of steel tube, section type and width (diameter)-to-thickness ratio are selected. Total thirty-four stub column specimens are tested under concentric load. From the view point of the maximum strength, current limiting width (diameter)-to-thickness ratio is practically appropriate.

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The Hyogoken-Nanbu Earthquake damaged a great amount of buildings in a various extent, seriously or slightly. We investigated 22 such buildings mainly located around the Sannomiya, Central district of Kobe city, where the seismic intensity (JMA) was evaluated as VII. To the seismic responses of these buildings, the evaluating method based on the energy equilibrium concept is applicable. And in this paper, the propriety of aseismitic property concluded by this method was proved by the relative situation of damages. We have attempted to obtain the relation between seismic damage and cumulative inelastic deformation. In addition, according to the damage situation of buildings, we have estimated the seismic energy input to buildings on the most serious area of the Hyogoken-Nanbu earthquake.

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The main items discussed in the present paper are as follows: 1. Why did the authors assume plane SH waves as an incident wavefield though the heavily damaged belt zone is situated just above the fault sources? 2. Hyperelement method developed about 20 years ago is less applicable to vertical as well as horizontal boundary value problems of deep irregular underground structure than the conventional methods such as FEM and FDM. Why did the authors choose a hyperelement method? 3. Though there was very few earthquake acceleration records observed in the heavily damaged belt zone, the authors concluded without any verification that simulated peak acceleration distributions coincide with roughly estimated observed distributions of structural damages. 4. The authors performed multiple publication.

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The authors thank Dr. Yuzo Shinozaki for his discussion and the answers are as follows. (1) The authors think that the investigated incident wavefield; plane SH wave propagating along the fault axis with vertical incident angle of 45° and 0°, is reasonable considering the radiation pattern of the source mechanism of the earthquake. The SH wave incident analysis in the original paper does not mean the 2-D anti-plane analysis (2) The hyperelement method is adopted to show the ground motion amplification due to the deep irregular underground structure by using possibly simple model at earlier stage investigation because of the computational efficiency in spite that the method reduces the degree of freedom of modelling of actual geologycal structure. One another reason why the authors selected the method is that the scattering wavefield can easily be decomposed from the total wavefiled. (3) The authors think that the ground motion amplification characteristics based on the discussor's model cannot be applied to a discussion of the interpetation of the heavily damaged belt zone because the model is quite different form the geological structure in Kobe City. (4) As for the indicated publications to several journals, the authors had no intention of multiple publications, but they intended to appeal the idea to many persons of various fields; not only earthquake engineers but also seismologists, and not only Japanese but also persons in the world through the journal with world wide distributions.

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