The purpose of this study is to estimate the rheological properties of the cement paste through the setting process. There are some type of measuring methods for rheological properties, among that we chosed the dynamic measuring method by shear wave propergation. By this method continual measurement for same specimen is possible through the liquid state after mixing to the hardend state. In the present paper, velocity and attenuation measurements of shear wave were made to obtain the dynamic viscoelastic constants of cement paste through the setting process and variation of these constants were studied as a function of frequency in the range from 4 kHz to 500 kHz.

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A procedure for synthesizing a three-dimensional earthquake ground motion to be used for aseismatic structural design is presented. This paper proposes that the synthesized ground motion can be obtained as output sequence of dynamical system having an appropriate pulse-transfer-function under inputting a required innovation process to the system. Sections of this paper are as follows; 1. Introduction 2. Dynamical system generating the simulated earthquake ground motion 3. Stochastic difference equation for the dynamical system 4. Earthquake-engineering meanings of pulse-transfer-function and innovation process 5. Generation of synthesized earthquake ground motion 6. Earthquake records used for studies 7. Pulse-transfer-function expressing information on observation site 8. Innovation variances expressing information on epicenter and earthquake transmission 9. Example of synthesized earthquake ground motion 10. Conclusion

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The inelastic dynamic analysis of multistory unbraced and braced steel space frames with H-shaped columns is performed to investigate the inelastic behavior under two-directional and one-directional excitations. The frame is idealized as a system with rigid floors and beams, and the sinusoidal waves are selected for the base acceleration. The results are summarized as follows: 1) The displacement responses of the frame under two-directional excitations in general are greater than those under one-directional excitation. The first floor horizontal displacement responses of unbraced frames in x-direction increase with the increasing axial force under two-directional excitation, although those frames are still stable under one-directional excitation. In the case of the braced frames, the first floor horizontal displacement in x-and y- directions increase with the increase in the rotation angle because of large change of axial force induced by the braces. 2) Designing to have the optimum strength distribution of columns prevents the frames from the increase of relative displacement under two-directional excitation. The optimum strength distribution of columns under two-directional excitation differs from that under one-directional excitation.

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The effective bending strength determined by the elastic buckling of constituent members for three-way doublelayer lattice plates is derived, considering the effects of the dimensions and connecting elasticity of joints. The strength is expressed as a surface in the Mx-My-Mxy space, and its property is discussed varying the rate of the bending rigidities of chord and web members for some dimensions of joints. The strength is compared with that of the pin-jointed truss of the same members. This rate is between zero and four, and usually larger than unity when the jointing rotational spring constant is several times larger than the bending rigidity per unit length of bars, EI/l.

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In this paper, the advanced torsional analysis of beam is composed and formulated by finite element method, which analysis include the effect of shear deformation caused from warping torsion. By using this torsional analysis of beams, the shear deformation are evaluated in torsion problem of thin-walled open section and closed section. This computational method is applied to the whole torsion analysis of a frame structure which is idealized by a thin-walled section beam, and several examples show good correspondences to the results of other method or to measurement values.

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Vertical simple harmonic oscillation of a circular disc on an elastic half-space is investigated theoretically. The theory is then examined numerically. This problem, dynamic compliance of a circular disc, has not yet been solved in general form ; rigorous formulation is only known in case of a rigid disc. In this paper an extension of this theory is presented. The new theory is derived from an investigation of the elastic medium alone. As a consequence, the result obtained is valid against any deformable discs such as elastic plates. The theory brings eventually a basic relation between the vertical displacement of the disc and the normal stress at the contact surface. It is a linear integral transformation. Its integral kernel, which is obtained explicitly for the first time in the present paper, is expressed as a definite integral of some higher functions which are easily calculated numerically. By solving simultaneously the basic equation presented here and the equation of motion of the disc, one can readily take the dynamical interaction between the disc and the elastic medium into account. The present theory is examined numerically, too, by applying to the case of a rigid disc whose result is known. In spite of the quite different formulation, the present theory surely gives identical solutions.

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This study deals with the reinforced concrete columns, which are designed according to the 1962 AIJ R/C building code and are subjected to antisymmetric bending shear until flexural or shear failure. The main objectives of this paper are (1) to investigate the two-dimensional deforming modes of the column, and (2) to clarify the relationship between the deflection angle of the column and the crack displacement, ie, the relative displacement of concrete at the both sides of the flexural or shear crack. After the diagonal shear failure, the averaged transverse strain at the middle part of the column was uniform and remained almost constant during the cyclic loading as shown in Fig.30. There existed a definite relation of Eq.(61) between W_y, and R_<max> (maximum deflection angle so far). In case of flexural failure, there existed a relationship of Eq. (59) between the crack width W and the current deflection angle R, where g was the distance from the neutral axis to the measuring location of the crack width.

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In the steel structures consisted of RHS-columns and H-beams, it is important to proportion the details of connections, which should have sufficient load carrying capacity and appropriate rigidity to withstand the transverse force on column walls caused by the normal stress at beam flanges. The purpose of the present paper is to investigate the local failure of RHS-column to H-beam connections with exterior diaphragm in rigid steel frames. The factors affecting the local failure are the width-to-thickness ratio of RHS-columns and the shapes and dimensions of diaphragm, in addition to their material properties. A number of simplified model tests are carried out to investigate the effect of the factors on local failure of connections. The work reported in this paper clears the effect of dimensional parameters on local strength of connections qualitatively. The effect of the difference of manufacturing process of RHS and transverse beam flange on local strength are also investigated.

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In many tall steel structures having heavy members and high strenght steel, welding joints have come to be adopted in beam-to-column connection. It is considered that the brittle fracture occurs, when structures are received repetive large strain due to a strong earthquake. It may be that main factors of the brittle fracture are the stress level in the column, a welding method and the stiffness of column web with doubler plates. For such joints having heavy steel members, it remains as important problem how to design beam-to-column connections. This paper describes the influence of the stress level in column on the charactristics of fracture and the structural design method of beam-to-column connections. 10 full scale specimens of sub-assemblage including beam-to-column connections are experimented applying axial force and bending moment. A constant axial force of -0.45, -0.2, +0.1 (axial load/yielding axial load of column) was applied at the column and cyclic vertical force was loaded at the end of beam. The results obtained from the above experiment are as follows, 1) In early stage, the brittle fracture of the specimen applied a tention axial force at a column occure and a crack propagats in the direction of the through-thickness of column flange. 2) The specimens reinforced with doubler plates at column web within connection are more fragile then non reinforced.

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In this paper, effects of bulge shape and normalization on the tensile strength of gas pressure welded joints of reinforcing steel bars were investigated by the aid of the experimental design method. As the result, an adequate bulge shape was found out and also the effect of normalization on the tensile strength was confirmed to real welded joints of reinforcing steel bars. First an appropriate procedure of gas pressure welding of reinforcing steel bars for use in structures for low tempertureservice was proposed. Secondly, an evaluation method of normalization of welds by hardness testing was proposed for the quality control at the site.

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