This paper disscusses the method of evaluating tactile response of various materials and its applications. 1) A specific material can be evaluated by plotting its data in the space coordinate of warmth, hardness and roughness. 2) Building materials can be classified into seven groups by applying clusteranalysis. 3) The value of affect or dryness of a specific material can be calculated from those of warmth, hardness and roughness factors. 4) The effectiveness of the evaluation method above were confirmed by the building engineers through the questionnairs.

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ln this paper author proposes the estimated formulas. They show the concrete streneth of arbitrary ages in the different curing conditions : water, seal and air at 20℃ and below 20℃. They ・cover from early age to late. Natural oortland cement and higher strength oortland cement are used in the experiment.

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In this paper, we suggested an equation which represents the hydration process of cement-mortar under any drying conditions. And the validity of the equation was confirmed experimentally.

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We have proposed the method of measuring the acceleration of the hammer as a standardized testing method of the impact bending strength of brittle materials. The specimen resists the impact load by the strength of the material and the body force of the specimen. The former is named "Impact Bending Strength (E_s)", the latter is "Inertia Resistance (F_I)" and sum of these is named "Impact Bending Toughness (P)". In this paper, the impact bending properties of cement-mortar specimen are examined. In § 4, the deformation of the specimen under impact bending load is investigated by the elastic analysis and some experiments. In § 5, the calculation method of the "Inertia Resistance (F_I)" is described. The method is based on the theory that substitute the deformation and movement of the specimen for the revolution movement of a reged body and the theoretical calculated results almost coincides with the experimental results in the experiments to determine whether the assumption used in this theory is good or not. "Inertia Resistance (F_I)" increase with the hammer's speed being faster and when the specimen shows localized bending defor-mation (E_I) is smaller than the (F_I) when the specimen deforms in the whole span. In § 6 and § 7, the values of (F_s) and (P) of the specimens are investigated by several impact bending test. It was clear that the specimen has least "Impact Bending Toughness (P)" when the hammer strikes the specimen at the speed that corresponds to the period of first normal mode of the specimen. "Impact Bending Strength (E_s)" decrease with the hammer's speed Vo being faster in the slower limits than the speed that corresponds to the period of first normal mode of the specimen, but (F_s) is constant in the higher speed than that.

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A series of studies on earthquake disasters has been conducted from a standpoint that all the disasters from direct to indirect, immediate countermeasures and subsequent restoration are linked and mutually correlated phenomena and therefore both of damaging and restoring processes should be considered simultaneously. As a part of studies in this direction this paper describes a factor analysis on damages of residential and nonresidential houses, of commercial, industrial, and agricultural structures etc. and on functional deterioration of lifeline, traffic and other public systems due to the 1982 Urakawa-oki earthquake. The fundamental data used are obtained mostly by the questionnaire survey carried out for all the municipalities of city, town and village in Hokkaido district, Japan. The major results obtained are i ) Physical and direct damage to structures are strongly affected by the seismic intensity at the sites where they locate, and ii ) Functional deterioration of public facilities as water, gas, traffic and other systems are governed not only by the seismic intensity but also by the areal size characterized in terms of population. Namely, it was reconformed quantitatively that the earthquake disasters are much more complicated in city areas than in less populated town and village areas, even if the seismic input itself is identical.

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During a strong earthquake, the base mat of a nuclear reactor building may be lifted partially by the response overturning moment. And it causes geometrical nonlinear interaction between the base mat and rock foundation beneath it. In order to avoid this uplift phenomena, the base mat and/or plan of the building is enlarged in some cases. These special design need more cost and/or time in construction. In the evaluation of the uplift phenomena, a parameter "η" named "contact ratio" is used defined as the ratio of compression stress zone area of base mat for total area of base mat. Usually this contact ratio is calculated under the combination of the maximum overturning moment obtained by the linear earthquake response analysis and the normal force by the gravity considering the effect of the vertical earthquake component. In this report, the effect of vertical earthquake component for the uplift phenomena is studied and it concludes that the vertical earthquake component gives little influence on the contact ratio. In order to obtain more reasonable contact retio, the nonlinear rocking analysis subjected to horizontal and vertical earthquake motions simultaneously is proposed in this report. As the second best method, the combination of the maximum overturning moment obtained by linear analysis and the normal force by only the gravity without the vertical earthquake effect is proposed.

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It was discussed in the first report that by the Ohno's anti-synmetrical shear loading test on the shear joints with the various types and numbers1 of cotters or teeth-marks, the ultimate strength had depended upon not only the shearing area but also the way of adding force and the figure of cotters or teeth-marks and also by the elastic stress distributions, the destructive cracks had occured towards the principal atresses and there had existed an obvious certain relation between the apparent plastic sphere γ_t and its stress slope Δ on the surface of destruction, furthermore by using these relation, the method of estimating the shear strength of cotters or teethmarks of the complicated shape from the elastic stress distribution had been offered. In the present paper, we will report the experimental results about the forms of distruction and the property of strength of shear joint with 1 to 3 teeth-marks by the various shearing tests with short shear spans, and in these cases there exist the same relation in the previous reports between the apparent plastic sphere and its slope of 「criterion ratio stress of destruction」 curves on the surface of destruction by the elastic stress distributions of all specimens used in the experiments.

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This paper describes a calculation method of the ultimate strength of a steel H-section with an unreinforced hole which is subjected to a combined stress under a bending moment, a shearing force and an axial force. The strength equation is derived from a statically admissible stress field based on the lower bound theorem of the limit analysis. The experimental studies wear down on the beams with the openings subjected to a combined stress, in order to obtain the mechanical characteristics such as the strength, stiffness and deformability. The strength equation is examined by comparing it with results of the experiments so that the equation is used as a tool for assessment of strength.

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The purpose of this study is to verify the relation between plastic collapse load and eccentricity of weak beam type space frames. One story, one span and one bay small-sized steel space frames are tested under the horizontal load which are applied in the direction of 0° and 45°. It can be concluded that the experimental plastic collapse loads are well predicted by the theoretical ones.

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The coefficient lists on the term of loading (fixed end moment and horizontal thrust at fixed end) are expressed in the five significant figures with the values of uniform section girders as unit and these are made on the following three conditions. Condition 1 Lengths of rigid zones at both ends are ξ_ιl'=γ_ιl=ξ_κl'=γ_κl=(0.00〜0. 30) l calculated with an interval of 0. 02 l. Condition 2 Numbers are given to each six types of working load. Condition 3 No. 1 is omitted. No. 2, 3, 4 are made. No. 4 is made at the load working point α=0. 2, 0. 3, 0. 5. The list on the shearing force at fixed end is omitted since the shearing force can easily be calculated from the fixed end moment shown above and etc. These calculations were made by computer HITAC M-180 and microcomputer FM-11.

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A number of reports concerning buckling behaviors of shallow spherical shells have been published for a long time. Recently, the main theme of those investigations is the following ; i ) the order estimation of strains, constitutive equation, and so on. ii ) the consideration of the influence of loads for instance conservative forces or nonconservative forces. In this paper, the influence of different strain-displacement equation for the axisymmetrical buckling behaviors of clamped deep spherical shells is described. And by computing the eigen value at each load level, the asymmetrical buckling load of deep shells is estimated. In result, the difference of the strain-displacement equation influences the buckling behavior of deep shells. Concerning deep shells the asymmetrical buckling loads for many buckling modes are much the same. Therefore the deep shells sensitively react upon the initial deformation constituted of those buckline modes

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The rectangular hollow sections (RHS) are produced by several manufacturing methods. In the manufacturing process, residual stresses are introduced by cold-forming and welding, and material strength is increased by the work-hardening. These two effects will influence the behavior of the beam to column connections. This paper describes the measurement of residual stress and the effects of residual stress and the workhardening of materials on the strength of RHS-column to H-beam connections under horizontal force. Three types of RHS are used. (1) RHS formed by cold rolling (2) RHS fabricated from two channels formed by cold pressing (3) RHS built up by four plates In addition to those, stress-relieved RHS produced by method (1) is also investigated. The results are as follows : 1) The work-hardening strongly influences the strength of the connection. However, the effect of residual stress is not so large. 2) The yield and the maximum strengths are estimated by Eq. (2) and Eq. (7) respectively. 3) As the maximum design formula, Eq. (10) is available regardless of the difference in manufacturing method of RHS.

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Wide-flange steel beam-columns are tested under constant vertical and two-dimensional monotonic or cyclic horizontal loads in order to make clear the three-dimensional inelastic behavior, and to grasp new problems which do not appear in the plane frames. As the experimental parameters, the direction of the horizontal load and vertical load ratio are selected. Experimental behavior is investigated and experimental results of maximum horizontal loads are compared with the results computed by strength formulae. Rigid plastic analysis is performed to investigate the state of collapse mechnism. The summaries are as follows ; 1) For beam-columns subjected to monotonic biaxial bending, it seems that displacement v is limited to a certain value, different from in case of uniaxial bending.2) Mechanism curves estimate the general tendency after the maximum load attained. 3) As to the cyclic behavior, H-^^-__υ loops start to drift away from original point in one direction when the displacement amplitude becomes large. 4) Load-deflection relations become more stable as the angle θ becomes large. 5) Strength formulae used in the plastic design of steel structure are conservative. 6) Maximum Strenth of beam-columus subjected to biaxial bending can be predicted by using eqs. (11), (13) and (14).

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The purpose of this paper is to investigate the differential settlements of frame structures on cohesive soils which are layered from ground surface to considerably deep stratum. In this paper, a three-dimensional finite element method has been presented to analyze the structure-foundation-soils interaction. The following idealizations have been made in the method I 1) The three-dimensional element which has been derived from the effective stress principle so as to represent the shear settlements and the consolidation settlements is used for the soils. 2) The linear elastic beam element is used for the superstructures and the foundations. 3) The elasto-plastic linkage element which has been expressed as a function of effective overburden pressure and slip along the pile shaft is used for the joints between piles and soils. And further, the preliminary analysis for the non-conforming condition between the element of foundations and that of soils as well as the analysis for the size of finite element mesh have been executed. As a result, we conclude that the present method is suitable to analyze the settlement process of both frame structures with spread foundations and those with friction pile foundations on poor grounds.

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