The life prediction method developed in the 1st report for the low-cycle fatigue of notched specimens in completely reversed loading was applied to the low-cycle fatigue accompanied by (1) a change of stress amplitude and (2) the mean stress. The effectiveness of the method for these two cases is discussed with the measurement of the strain at notch root and the analysis by the finite element method. When a circumferentially notched specimen is subject to overloading, the strain range at notch root after overloading becomes smaller than the value without overloading. The strain ranges at notch root under the same stress amplitude and different mean stresses are nearly equal to each other and the crack initiation periods become nearly equal.

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The present paper deals with the effect of water environment on the fatigue behaviors of plastics reinforced with woven cloth of surface treated glassfiber (GRP). The penetration of water into GRP is known as a diffusion process of water molecule. The diffusion is accelerated by internal defects caused by fatigue. The debonding of the interface between fiber and resin matrix observed with the variation of the diffusion coefficient due to progressing fatigue damage, and the variation depends on the angle, θ, between the warp and the load direction. When specimens are subjected to fatigue in water, the diffusion of water is significantly accelerated. The fatigue life decreases, especially for θ=45°. These fatigue behaviors are proved through observations by means of a scanning electron microscope.

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This paper is concerned with an extension of Love's solution for the axially symmetric problems in the theory of elasticity. The principal results are as follows. (1) Love's solution is generalized such that it may be possible to apply it to the problems accompanied with both torsional deformations and body-forces, because Love's solution in its usual form is inapplicable to the foregoing cases. (2) The generalized Love's solution has the completeness of solution for the axially symmetric problems. The completeness of Love's solution in its usual form is only assured for the cases of torsion-free deformations with no body-force but in z-direction. (3) The torsional solution obtained from the generalized Love's stress function is equivalent to the solutions of other known methods. (4) An attempt is made to investigate a general functional form of Love's stress function which can be applied to any practical problems. (5) The stress function for body-force problems is investigated, and examples of its application are shown.

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The authors propose two theories of the Front Surface Method and the Back Surface Method on residual stress measurement in the whole cross section of a multilayered plate by X-ray. In a multilayered plate composed of two or more plate elements of different material, a standard temperature of measurement must be expressed clearly because of being affected by thermal stress caused by temperature change. The authors derive a stress compensation coefficient. As application of the new theories, the residual stress distributions in a Cr-electrodeposited two layered plate and a bimetal plate are measured by the Front Surface Method and the practicability of the theory is confirmed.

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From among many problems contained in this experimental method by which the stress analysis can be performed using only the indirect informations from the surface layer, the above two were picked up and the case of "a tension of a strip with semicircular notches" was investigated. As the specimen, an aluminium alloy strip regarded as isotropic solid that obeys von Mises' yield criterion and the flow theory was used and as the coating material, epoxypolysulfide copolymer was used. Mainly, the following conclusions were obtained: (1) The necessity of taking the reinforcing effect into consideration. (2) The appropriateness of the assumption V²ε₃=0 in a state of the restricted plastic deformation. (3) The unsuitableness of applying the deformation theory to the problems of this kind.

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The paper is concerned with the linear dynamic response of arbitrary shells of revolution to time-dependent loads. The dynamic response problems of shells of revolution to time-dependent loads are important in engineering design. The studies on the dynamic response of axisymmetrical shells, however, are almost limited to the simple geometries such cylindrical shells and spherical shells. Then in this paper the authors derive the basic differential equations on the dynamic response of arbitrary axisymmetrical shells under time-dependent loads by extending Budiansky's method based on Sanders' shell theory. In the numerical analysis of this problem the spatial derivatives are represented by usual finite difference forms and the acceleration terms are treated with the backward difference formula proposed by Houbolt. Three numerical examples - a cylinder under a semi-sinusoidal pulse, a cylinder and a pressure vessel under a blast loading are presented.

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An approximate analysis of the nonlinear, mixed-type differential equation for inviscid transonic flows past a sinusoidal wall is made using the nonlinear correction theory, which was proposed by Hosokawa to improve the linearized transonic flow theory. In order to execute analysis for the flow far from the wall, the nonlinear correction theory (considered to be valid only near the wall) is applied for a streamline near the wall considered as a new wall to calculate the flow farther than that and continue this process successively to obtain many streamlines which clarify the entire flow field past the original wall. This method gives a good survey of various transonic flows past the sinusoidal wall, including periodic appearance of sonic and shock lines in the flow field which define supersonic pockets in subsonic main flows as well as subsonic pockets in supersonic main flows.

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There is often found a vortex breakdown as an abrupt velocity and structure change at some position along an axis of a swirling flow. To make clear the hydrodynamical characteristics of the breakdown of a swirling cavity flow in a diverging circular duct, experimental observations and hydrodynamic examinations of the breakdown have been made about the behavior of the cavity and velocity or pressure distributions of water on the outside of the cavity. The experimental investigations for various swirling cavity flows revealed quantitatively large velocity changes at downstream of breakdown and close relationships between the shape of the cavity and the states of liquid swirling motions. The effect of the varying duct area on the abovementioned relationships also examined by comparison of the results in the diverging circular duct with those in the straight circular duct.

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This second report describes the experimental results about the gas flow between tubes arranged in single column, single row, and double rows. The word "column" indicates a line of tubes in the direction of the gas flow, and "row" indicates a line of tubes perpendicular to the direction of the gas flow. Visual observations disclose that the vortex formation region and the Coanda effect have dominant effects on the structure of the gas flow in the three types of tube banks. The variation of the Strouhal number with the tube spacing is strongly dependent on the size of the vortex formation region. The gap flow between adjacent tubes normal to the flow behaves as a two-dimensional jet. It was found that in some tube spacings, the jets coalesced with each other due to the Coanda effect, and in an extreme case, non-uniformity was observed in the bulk flow.

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In this report, an analytical method is presented for the synthesis of a plane four-bar mechanism to generate approximately a desired curve. This method produces such a curve generator that the coupler point may pass through precision points on the desired curve in the stationary coordinate system and the higher order differential coefficients of the coupler point coordinates with respect to an input variable may coincide with the ones of the desired curve at each precision point. Moreover, a numerical procedure is worked out for evaluating the difference between a desired curve and a generated curve.

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