Using samples of various different gradings blended with single sized aggregates, sieved sand and gravel with particle sizes of from 0.074 to 19.1mm, an effect of particle size distribution on solid content-packing density-of aggregates by jigging, rodding, and shoveling procedures has been discussed experimentally. It is supposed that the solid content of single sized aggregate corresponds to influence of particle shape on solid content blended in the same packing efforts. The single sized aggsegate is separated at 1/2 size ratio of sieve opening of retained on to passing. In the previous paper, the values of four statistics-Mean, Standard Deviation, Skewness, and Kurtosis-on the fineness modulus scale of continuous distribution of particle size were proposed in order to evaluate numerically the grading of concrete aggregates and named the Grading Parameters on the FM. The solid content of blended aggregates with fairly free grading can be estimated within closely error (≒±1% by vol.) by using these parameters and following equations. D=α(SD-0.29)+Σ^^n__i=1f_i×d_i where α=8.2-(1.2SD+5.4S)/K D : solid content of blended aggregate, % by vol. d_i : solid content of single sized aggregate (size ratio of sieve opening : 1/2), % by vol. f_i : fraction of single sized aggregate, by vol. SD, S, K : standard deviation, skewness, kurtosis of the Grading Parameters based on the FM respectively.

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The stability of the periodic solutions is examined in Part 4. Here, it is shown that we have to conclude the stability of periodic solutions of the equations of motion with multi-degree-of-freedom by solving the complex eigenvalue problem. Meanwhile, in order to get approximate periodic solutions we usually have to solve nonlinear algebraic equations with applying iteration procedure such as Newton-Raphson procedure, because they cannot be solved algebraically. However there are some cases in which they are solved algebraically, and we can get approximate solutions for nonlinear free and forced vibrations and determine the boundary regions of instability for subharmonic oscillations and parametric excitations.

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The purpose of this series of experiments is to investigate the energy absorption capacity of H-shaped steel columns subjected to earthquake loads. Energy absorption capacity subjected to cyclic loading with varying deflection amplitudes is affected by the hysteresis of deflection and the lateral deformation. The experimental study made it clear that the cumulative damage rule is applied to varying loads by using the relationship between energy absorption capacity and plastic deflection amplitudes of columns subjected to monotonic loadings and cyclic loadings with constant deflection amplitudes.

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The aims of this paper are to develop, without loosing generality, the approximate theory of the rigorous governing equation of motion for a thin-walled open section derived in the part 1 and further to present the linear theory through linearizing this nonlinear approximate theory. The approximate theory is derived under the following assumptions (1) The wall of the thin-walled open section is thin in comparison with the size of the cross section. (2) The shape of the cross section is small as compared to the radiuses of the curvature and torsion of the axial curve. and it is applicable to the problem of a thin-walled open section, whose axial curve forms a space curve, under occurring the large displacements and large rotations, the transverse shear deformation and the deformation of the cross section. For the linear theory, we can hold the linear theory including the deformation of the cross section and the transverse shear deformation, the linear one based on the Bernoulli-Euler hypothesis, the linear one considered warping in the Bernoulli-Euler hypotheses, and lastly the linear one including the transverse shear deformation. Furthermore the relations between the linear theory derived under the Bernoulli-Euler hypothesis and the theories by Vlasov, Wempener etc. are discussed through the problems of twisting of a cantilever beam. It is concluded that the expression of warping expanded into power series holds the good approximation to the past theories.

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The purpose of this paper is to explain the bending of elastic plates with opening hole analytically in application of theory of thin plate. This analytical method used in the paper is based on a complex variable method. Part One is for square plates with eccentric circular hole. Boundary conditions treat the case of clamped edge and simply supported edge for a outward boundary, and free edge for a interior boundary. Various values obtained this analysis is quantitative sufficiently.

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The purpose of this study is to make clear theoretically general buckling behaviour of Cylindrical Reticulated Shell Roofs (C. R. S. R) having cylindrical surface composed of regularly fairly fine, triangular grids formed by a single layer of prismatic structural members on the longitudinal and diagonal lines. In this paper (Part 1), nonlinear basic equations of C. R. S. R. subjected to external pressure are derived by planely continuous treatment of a curved beam and then under the boundary conditions that the two ends of the structure are simply supported and the two generator edges are arbitrary, nonlinear basic equations are solved in the case of symmetrically large deflection and bifurcation buckling with respect to longitudinal center line.

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In this paper, the model of the VORTEX-INDUCED VIBRATION of a circular cylinder is investigated. The wake oscillator whose length alternates was proposed in author's previous paper. Now, author proposes "the Model of the Vortex-Induced Vibration of Circular Cylinder", which is represented by eqs. (10a, b, c). These equations are of the coupled-oscillation of the wake oscillator and the circular cylinder mounted elasticaly. The approximate periodic solutions of the steady state are obtained by eqs. (18a, b, c). The behaviors of these solutions are shown in Fig.1. It is indicated that the proposed model can be expressive of the properties of the vortex-induced oscillation of circular cylinder, i.e. i) synchronization, ii) sudden change of the phase shift between the lift and the displacement of cylinder, iii) double amplitudes response, iv) delay of the resonant velocity from the critical velocity, and from the velocity at which the maximum lift occurs. The resonant amplitude of the cylinder can be calculated approximately by eq. (19a). The results of eq. (19) are compared with the experimental results in Fig. 2. It is shown that both of the results are in good agreement. Fig. 5 to Fig. 12 are the comparison with the numerical solutions of eqs. (10a, b, c) and the experimental results. We can see that both are in good agreement not only in quality but also in quantity.

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As the third part of five serial reports, the test data of series-2 are shown in this paper. Loading system and computer system to controll it were more refined in conducting the series-2 than in series-1 reported in the previous paper. Test variables were initial natural period, intensity of the ground motion and column axial stress. Through the On-line test series-1 and series-2, it is found a) that the computer-actuator On-line system is a feasible method to simulate experimentally the earthquake response of reinforced concrete building frames and b) that the computer program OS-1 D can approximate well to the On-line simulation.

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In a theoretical analysis method it is necessary to assume a "suitable analytical hypothesis" prior to analysis, and with concrete structures, estimating "stiffness with good approximation of facts" applicable to conditions of repetitive stresses has remained as an extremely difficult problem to solve because of factors such as cracking. The authors previously proposed an analysis method on indirectly measured values not requiring a hypothesis of the stress-strain relationship as a method of investigating the mechanical properties after cracking of shear walls with steel frames. This method, in contrast to theoretical analysis methods generally used, makes analyses in the reverse direction. Briefly described, whereas in a theoretical analysis method the stiffnesses of materials or members are assumed to obtain the stiffness of a structure in order to determine deformations and stresses under external forces, this analysis method obtains deformation of the structure and stiffnesses of members from directy-measured strains and external forces, based on which stresses of members are determined. This paper examines the results of analysis on indirectly measured values obtained with 6 shear walls having steel and reinforced concrete frames of different methods of reinforcement, and reports on the influence of degree of restraint by peripheral frames on the elastic and plastic properties of framed shear walls. The results may be summarized as follows : 1) Prior to cracking of wall concrete and the peripheral frame, the wall panel is in a more or less pure shearing state, and strains and stresses of the frame and wall are distributed roughly antisymmetrically. 2) When the wall panel cracks, it forms a compression field, and since the peripheral frame serves as a whole to restrain the wall panel, the tensile stresses of the peripheral frame become fairly large. 3) The greater part of shear forces after cracking of the wall panel is carried by diagonal members of the wall concrete restrained by the frame, and wall reinforcement carries shear force more or less equal to the tensile strength of the concrete. The shear force carried by the so-called rigid-frame deformation of the frame is small. 4) The axial stress-strain relationship of a column is on the stiffness curve with the entire cross section including concrete of the frame effective during compressive stress, but during tensile stress, the relationship approaches the stiffness curve of only the structural steel and reinforcing bars as repetitive stresses are sustained. 5) The bending stiffness of a column differs according to the condition of axial stress and during tensile stress it more or less approaches the stiffness of structural steel and reinforcing bars only, but during compressive stress, concrete also works fairly effectively. 6) The shearing stiffness of a column also differs according to the condition of axial stress, and is close to stiffness of the entire cross section effective during compressive stress, but becomes fairly low during tensile stress. However, the degree of reduction is not as sharp as that of bending stiffness, and concrete also works fairly effectively against shearing stress. With regard to the analysis method of indirectly measured values : 7) The rates of analytical error e_1 of indirectly measured values of deformation are very small for all specimens and are about 0.05 to 0.15. 8) The rates of analytical error e_2 of indirectly measured values of stress are small for all specimens at the initial stage. When loading is repeated, e_2≒0.25〜0.30 is reached with the specimens SW6-A, B of small structural steel cross sections and the reliability of the analysis results is lowered. It is thought necessary for innovations to be made to bring the restraint conditions of stiffness closer to reality.

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It is important to study on the outbreak of fires in order to protect large cities in Japan against fires caused by earthquakes. In this papers, the spread of fires in the inside of building is discussed. And next, it is explicated how the building-factors have effects on the spread of fires in the inside of building. For analysis, statistics of usual-fires are used and processed statistically. Through the discussion, the identity and difference between usual-fires and earthquake-fires are considered. And in order to obtain the valid information for earthquake-fires from usual-fires statistics we fixed our eyes upon the stage of sprayed-fires with water hoses.

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This study deals with an analysis of occupant behavior in an office building under fire. The data for this pursuit are drawn from the questionnaire which was conducted on the occupants of 'Fukoku' insurance company building, Osaka, Japan, in which a fire had occured on the afternoon of April 6th, 1978. And the final aim of this study is to find out characteristic behavior patterns between three items of a) individual attributes such as occupation and sex, b) first action after perceiving fire and c) evacuation behavior. In this paper of Part 1, classifications of above mentioned items have been dealt with by using the quantification theories of case 2 and case 3 developed by Hayashi. And as the result, fourteen species of first actions after perceiving fire have been divided into four groups of behaviors which are F1 (take responsible actions), F2 (escape at once), F3 (call to others to escape together, remove valuables or waver in confusion) and F4 (wait for instructions). And eleven species of evacuation behaviors showing the reasons why the occupants had taken the routes to escape from the building have been also divided into five groups behaviors which are E1 (take a predetermined route), E2 (take a shorter route or choose a route instantly), E3 (take a previously indicated route), E4 (run after others) and E5 (follow instructions and guidance).

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Measurement of the air flow around the building simulated in the wind tunnel is a major problem for wind tunnel techniques. In this paper, a report is made on a trial anemometer which can measure the air flow suitable for assessing wind environment and the validity of such an anemometer. In the first step of the investigation, the thermistor-anemometer was improved so that it will possess high response and its response was examined by placing it in the pulse wind which fluctuates only in the main flow direction together with a hot-wire anemometer. In the next step, difference between the results of measurement of the air flow around the building by using the thermistor-anemometer and that by using the conventional hot-wire anemometer was examined in the wind tunnel, simulating the air flow around the building by using an urban model. Through the tests the following results were obtained. 1) The response of thermistor-anemometer can be indicated by reduction in variation, and its reductionis 20% at 10Hz, 41% at 20Hz and 56% at 30Hz. 2) If the reduction is corrected in connection with power spectral density, it is possible to analize quantitatively turbulence up to 40Hz. 3) The directional characteristic is smaller than that of the hot-wire anemometer (I-type probe), and so it is possible to measure the magnitude of the total velocity more correctly in the turbulent air flow near the ground level. 4) Mean wind velocity near the ground level measured by the thermistor-anemometer is higher than that measured by the hot-wire anemometer (I-type probe). The magnitude of the fluctuation component measured by the thermistor-anemometer is greatly different from that measured by the hot-wire anemometer at some flow points near the building.

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The purpose of the present study is to furnish fundamental data of exterior space design by analysing the correlation between visual effects and physical elements in order to estimate visual effects values. Certain public residential areas were considered for this purpose as positioning of buildings plays an important part, using a multidimensional index, visual effects values were measured. These results were analysed and a semantic structure of space was understood with physical elements such as trees, height of buildings and openness of space (sky factor) selected. Then the possibility of using a small scale model of buildings was considered in order to estimate the visual effects values by quantitative analysis. In considering Pleasantness, Unity, and Potency of sematic dimensions, measuring visual effects values was possible.

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In this paper, using the method of factor analysis, change of urban structure in Osaka region is clarified. From this result typical four cities are chosen for analysis. For these cities, change of urban structure is discussed and the relationship between urban structure and redevelopement is studied.

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In 1886 Japanese govecnmevt encployed german architect Ende & Bockmann, who formed aplan to concentrate government office buildings. This plan was very important urbanism in Meiji Era. The aim of this paper is to make clear process of this project-that is famous bnt notclear.

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