This paper presents the process of scaling of human senses on Hardness of building floors by means of sensory test, which are the basic knowledges for its evaluating method from a viewpoint of comfortableness. Sensory scales and evaluating scales based on the subjective judgement of Hardness were made by sensory test. Evaluating scales consisted of aptitude scales of Hardness at the action and estimate scales of fatigue after the continuative action of a long time. The sensory test was taken place with 28 sample floors included various materiales and structures, 5 human actions, 6 foot wears. The number of paneles was 10〜17 males and 17 females. The method of sensory test was 'the method of successive categories'. After the sensory test, we could obtain the scales of human senses on Hardenss of building floors and confirmed its effectuality by the considerations about the results of 'analysis of variance', the relations among the scales, and others. And it made clear from the relations between sensory scales and evaluating scales, that it was possible to evaluate Hardness of building floors by the physical scale which corresponded to sensory scales.

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The purpose of this study is to obtain the standardized testing method of the impact bending strength of brittle materials, by use of the simply supported beam type specimen under concentrated impact load. In this paper, we proposed the test method of measuring the acceleration of the hammer, and as concerns the physical unit, we proposed the impact bending strength by use of Impulse. We investigated the propriety of our proposal method by some experiments with the specimen of acrylic resin. The results is as follows. (1) The change with time of the strain of the impact bending loaded specimen is much same to that of the acceleration of the hammer. (2) When the impact strength is shown by impulse, it is easy to obtain the speed of the hammer when the specimen is just broken and easy to change to the impact strength shown by energy. By these results, the propriety of our proposal method was confirmed. And the basic properties of impact loaded specimens are obtained by the experiments with the model-specimen.

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The acoustic emission (AE) method was applied to trace the change of internal structure of concrete under various loads. Five series of experiments were carried out to obtaine the fundamental information on the AE behavior of plain concrete under monotonically increasing and repeated compressive loadings. Main results obtained by the pressent study are summarized as follows : 1) Accumulated AE counts at the maximum load increase with increasing compressive strength of concrete and the specimens cured in air are emittive than the specimens cured in water. 2) The characteristic points on accumulated AE events curve of concrete approximately correspond to the characteristic stresses of proportional limit and critical stress. 3) The Kaiser effect is valid in concrete when the load is applied immediately after unloading. 4) The degree of accumulative damage of concrete under cyclic loading can be predicted more exactly by applying AE technique than by examing permanent strain increments. 5) The fracture process of concrete may be accurately traced by the location search of local fracture and the detailed examination of onset directions of AE waves. 6) The number of high frequency components gradually increases with the increase in stress level and that of low frequency components also increases at the maximum stress, independently of the loading pattern.

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When relatively short beams of high-rise buidings are subjected to earthqake load, anti-symmetrical bending moment predominates. For reasons of economy, tapered and haunched beams have been utilized in some buildings. These beams are designed for working stress and checked for allowable stresses. Therefore, series of experiments were carried out to assess the plastic behavior and the seismic safety of the tapered and haunched beams. Experimental parameters were the "taper ratio" which was the ratio of the maximum to the minimum width of the flange or the depth of the beam and the "haunch ratio" which was the ratio of tapered to total length of hauched beam. In some specimens, the width-to-thickness ratio and the member length were also varied. Haunched beams were restrained against lateral displacement. The results from the study are as follows. (1) In the case of the beams with tapered and haunched webs, the rotational capacity and the energy absorption capacity were not smaller than those of the uniform beams with the largest cross section. (2) In the case of the beams with tapered flangs, the capacities were approximately equal to those of the uniform beams with the largest cross section. (3) It was found that the rotation capacity and the width-to-thickness ratio of tapered and haunched beams can be evaluated by those of the uniform beams with the largest and the smallest cross sections using the angle of taper of beam.

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It is important to proportion the details of RHS-column to H-beam connections not only for shear failure of joint panels but also for local failure of connections, when these connections are subjected to horizontal force. The present paper examines the interaction between the shear failure of joint panels and local failure of connections with exterior diaphragm. The connections with insufficient diaphragm faile according to the local failure, that is the local collapse of column, crack in weld and the local buckling of diaphragm. The deformation capacity and the absorbed energy of these connections are less than those of connections with shear failure of joint panels. The following formulae are suggested for estimate the strength of connections For yield strength : when M_<Ly>/M_<Py><1.0 M_<cy>=M_<Ly>…(8) when M_<Ly>/M_<Py>≧1.0 M_<cy>=M_<Py>…(9) For maximum strength : when M_<LU>/M_<Py><1.7 M_<cu>=0.78M_<LU>…(10) when M_<LU>/M_<Py>≧1.7 M_<cu>=1.33M_<Py>…(11) It is necessary to satisfy the following condition in order to prevent the premature local failure of connections. (B/2+h_D)/t_D≦24/√<σ_<yD>>, M_<Ly>/M_<Py>≧1.0

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In this paper, a new design method of tension-type connections with long-through bolts is developed and their structural properties are investigated by several tests. Summary of results obtained may be as follows ; This type connections have efficient deformation capacity by the restraint of the beam end-plates. The decrease of the introduced axial forces of bolts has a little effect on the load-deformation characteristics. The stiffness of the long-through bolt may be evaluated as that the stress transmission angle is about thirty degress. It is proper to consider that the short-time strength is about seventy percents of the breakage load of the connection.

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In this paper, the method of direct design based on the limit analysis of high strength bolted tube flange joints subjected to tension is proposed. The validity of the method is confirmed through experimental investigations as in the case of Part 1.

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In general the foundation ground is considered as an elastic, isotropic and homogeneous semi-infinite solid. But the soil is deposited in horizontal layers and the elastic properties differ in horizontally and vertically. So we will consider the case of horizontally isotropic and vertically aeolotropic medium. Such a medium is called "transversely isotropic". In the present paper we deal with the propagation of vibrations of a semi-infinite transversely isotropic solid that is subjected to a vertical point exciting force on its surface, now known as the "Dynamic Analogue of Boussinesq's Problem". The problem is axisymmetry and its solutions are obtained by Hankel transformation. By use of these solutions, we will discuss the characteristics of displacements.

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