The objective of this paper is to describe photoelastic analysis method used in the determination of the stress distribution produced by shearing loads in JIS test specimen standardized of shear tests for concrete. Apparatus and procedure for both push-off test and anti-symmetric shear test are outlined, and test results for one of the shear tests investigated are compared with analytic predictions. The experimental results for boundary stress and the map of directions of principal stress over the entire area are in fairly close agreement with wire strain gage and brittle coating method.

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A problem regarding torsional stress produced in the straight square bar with a square hole rounded the corners, which is twisted by couples applied at the ends, is investigated in this report. The models of the hollow square bar varied systematically the dimensions of the wall thickness and the radius of curvature of the corners are made of epoxy resin, and then stress analysis by means of scattered light photoelastic method is carried out after stress freezing for the models.

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It is necessary to know the effects of stress on the rotating components under actual rotating conditions because of the construction of high speed rotary machines. The stress distribution in a simple rotating body such as a disk, wheel or turbine rotor, due to centrifugal forces, has been reported both theoretically and experimentally as well as in experimental solutions in photoelasticity. Little work, however, has been done regarding a complicated rotating body. This experiment, therefore, has been conducted as a photoelastic analysis of the disk and blade in the dovetail region under actual rotation. And it investigates the stress distribution and the stress intensity factor in an actual dovetail region of a rotating blade, using a parameter of (N/t) √r, consisting of polar coordinates r and θ measured from the crack tip, to determine the stress intensity factors KI and KII.

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It is often desirable and suitable for the investigation of stress in a body produced by its own weight and the stress analysis of shock waves to use the low Young's modulus materials in the photoelastic experiments. However, the gel-like materials are used to few investigations, as they are hard to deal with. The purpose of this paper is to appropriate gel-like materials for application in the photoelastic sandwiches method. Gelatine gel and Gelatine gel added to Formalin, as high sensitive photoelastic materials, and water-cured Urethane polymer and gellike Acrylamid, as low sensitive photoelastic materials, were employed to obtain the values of Young's modulus, photoelastic stress sensitivity, and photoelastic strain sensitivity. These materials were tested for several days, and the time effects on the above values were also discussed. Results show that Acrylamide gel of negative photoelastic sensitivity added to Gelatine gel of positive photoelastic sensitivity, could have no photoelastic sensitivity value.

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The Neuber's rule proposed by H. Neuber in 1961 states that the geometrical mean value of the stress and strain concentration factors at any stress-strain law is equal to the corresponding elastic stress concentration factor, even after the occurrence of local yielding. It was derived by a theoretical analysis of the stress concentration for the shear-strained prismatical bodies with arbitrary nonlinear stress-strain law. But up to now, it is extended to the two or three dimensional states of tensile stress and used for the study of low cycle fatigue without sufficient verification. In this paper, the present authors investigate the behavior of above mentioned two concentration factors by means of photoelastic coating method for metallic strip specimens with notches at both sides under uniaxial tension, and report so called Neuber's rule is not applied generally to the state of plane stress.

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