The agreement of WTO and TBT has led to an increase in the influence of international codes and standards such as ISO and IEC on world trade. There has been great concern in Japan, as a trading nation, that influence harmful to the national interest may arise through unfairness in the international codes and standards. This may be especially germane to Japan, since the U.S. has always had substantial free market competition and now the U.E. is also moving rapidly in that direction. Therefore, representatives in various fields (government offices, electric utilities, and manufacturing industries, etc.) held summit meetings in the period from 1997 to 1998 to discuss and establish a strategy for international codes and standards.

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This paper describes the necessity of consideration aerothermodynamic phenomena change in evaluating deterioration and damage of hot parts in power generation apparatus. Concerning the turbine cooled rotor blade which are critical hot parts of gas turbine, the metal temperature of long term serviced blades became higher than that of short term serviced one. This change was caused by the increment of heat transfer coefficient on rotor blades because of the increase in blade surface roughness. The effect of aerothermodynamic phenomena change on the damage of the turbine cooled rotor blades is discussed.

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In order to substantiate the safe operation of fast reactor plant components at elevated temperature exceeding 500C, an evaluation of structure integrity under the presence of crack-like defects is required to complement design assessment. CRIEPI has generated the guideline for structural integrity assessment for fast reactor plants. Part II of this guideline concerns flaw evaluation, and provides a simplified J-evaluation method to predict creep-fatigue crack propagation behavior. The revision of the guideline is currently under way to improve the predictability of the method. This paper gives an outline of the modification of the simplified J-estimation method using reference stress, including the consideration of elastic follow-up.

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"Specification for the design of crane structures" was issued in 1976 as JIS B8821. Since then, fatigue life of cranes has been designed as 2×(10)^6 cycles. Recently, some cranes have been used beyond the designed operation ratio because of demands of increasing transportation quantities. More long fatigue life has been cried for crane structures. Therefore, amendment for the specification has been carried out. In the revised specification, fatigue design curves of welding joints subjected to normal stress are composed of 15 curves depending on strength category of the joints, and the fatigue lives are covered in the range from (10)^4 to (10)^8 cycles. Fatigue strength under variable amplitude stresses can be evaluated based on the linear damage rule. Fatigue assessment can be carried out by using design stress, allowable stress and safety factors.

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JST is examining the project of "Failure and Knowledge Database" for the purpose of being utilized for R & D and operations in the field of science and technology. This database consists of three types of databases, "reports of sample cases", "factual data taken out from the reports" and "knowledge extracted by the specialists' analysis". By making these three databases related to each other, we intend to establish the system that will make the search results available "for anyone, at anytime and in any form".

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The crack growth behavior on steel compact specimens was investigated by the echo characteristic of surface wave emitted toward the end of notch under low cycle fatigue. The echo height reflected from the edge of crack and the round-trip propagation time from the surface wave probe to the edge of crack were measured for evaluating the crack growth behavior. The crack was generated from the edge of notch when the round-trip propagation time suddenly increased or the ratio of the echo height suddenly decreased. After that, The crack grew with repeating progress and stagnation alternately, and the compact specimen broke. Judging from the results of fracture surface observed by the scanning electron microscope, The fracture surface is a stripe pattern, and the distance between the lines corresponded to the part of the stagnation.

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Database for damage and trouble of structural components has been developed in the company network. It includes "Material and Structure", "Corrosion", "Boiler", "Vibration", "Thermal and Fluid" as the data series. Keywords to refer the database are provided in each field respectively. In order to take effect in education and transmittal of know-how to designers, countermeasure and precept are shown in each case. Cases of more than 700 have been generated in the database continuously.

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In the present study, fracture tests by hydraulic pressure were performed on corroded and/or artificially flawed colsed-cylindorical-vessels as well as similar new vessels. The results were analized and evaluated by fracture mechanics. Critical pressure for plastic collapse of all the vessels were predicted reasonablly by an equation which assumed a thin thickness with strain hardening material. The results revealed the condition for leak before burst (LBB). Fatigue life of corroded and/or flawed vessels were predicted based on the above results for fatigue crack growth and final plastic collapse evaluated by fracture mechanics. The prediction suggested that corrosion thinning upto half thickness of vessels could be allowed with carefull attention

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Reversed tortional fatigue test of sandglass type specimen with a small flat surface notch was conducted at room temperature for a pure iron and a reduced activation ferritic steel F-82H in a solenoid coil cooled by water. Specimen was not constrained lonitudinally to avoid the additional stress induced by magnetostriction. Magnetic flux density in specimen, about 0.7 Tesra, was in rotation magnetization condition. Initiation and propagation behavior of large number of small cracks were observed on the flat surface notch by using image processing technique. For pure iron, crack initiation became earlier and crack growth faster in magnetic field. For F-82H steel influence of magnetic field did not observed.

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Cyclic braking tests under extremely severe conditions were carried out using large one-piece brake discs having several holes in their flange. When the number of braking cycles was beyond a certain number of cycles, some tiny cracks occurred in the radial direction around holes were found. They grew in the radial direction of the brake discs. In order to examine whether braking torque is a driving force for crack initiation or not, the time interval was altered 10 times longer than the normal condition. The experimental results showed that the number of total cracks around holes after the same rotations decreased as the braking interval was extended. The crack length also decreased. These results indicate that the braking torque itself does have less direct effect on the crack initiation.

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This paper deals with the thermal stress problems of an elastic solid with a rigid spherical inclusion under a uniform temperature change. It is assumed that there are partially debonded interfaces between the surfaces of the inclusion and the matrix. We use a body force distribution method for the stress concentration problem. For this purpose, we apply the fundamental solution for axisymmetric body force problems of elasticity. The thermal stress fields are expressed by the elastic field due to temperature and the elastic filed due to body forces. Stress distributions around the inclusion are shown, and compared with the results for an elastic solid with a partially debonded rigid sphericaal inclusion under tension.

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The paper presents a axisymmetric solution for the stresses and displaements in an elastic thick plate containing an oblate spheroidal inclusion under axisymmetric bending around the z axis. The related spherical cavity and inclusion problems were solved by Tsuchida et al. by using Boussinesq's displacement potentials. The surfaces between the inclusion and the matrix are assumed perfect bonding. The solution is based upon Boussinesq's displacement potentials. Numerical examples are given.

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The stress concentration factor of cyclic notches is influenced by the notch root radius, the notch depth, the notch pitch and so on. Therefore, the concept of the equivalent ellipse is not directly applicable to cyclic notches. In this paper, the solution is given for a half plate with cyclic notches under uniform normal stress at infinity. The formulation of this problem is treated as a Hilbert's problem and complex variable method is used to obtain the solution.

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In this study, fatigue tests had been carried out to investigate the optimum value of deformation of notched specimen by roller-working. Here, the specimen which has a deformation value of 0.25mm is tested. The deformation values are 0,0.5 and 1.0mm to compare to the former testing results by keeping the final shapes and dimensions except for deformation value. The main results are obtained as follows : (1) The potimum value of deformation of notched specimen by roller-working is 0.5mm. (2) Fatigue strength of notched specimen by roller-working increase with increasing plastic deformation value when the deformation value is les than 0.5mm, but when the value is larger than 0.5mm the result is opposite.

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The purpose of this study is to clarify the cause of difference between analytical reslut and experimental result. Hydro forming analysis was carried out at first. After that, impact crash analysis was carried out. In order to investigate the effect of hydro forming process such as wall thinning, residual stress and residual strain on impact crash analysis, the anslysis considering the manufacturing process was compared with that not considering the manufacturing process. The summary of reslts obtained through the present study is as follows : (1) The plastic strain caused by hydro forming affect on the deform behavior mode and absorbed energy in impact crash analysis. (2) The wall thinning caused by hydro forming doesn't affect on the deform behavior mode and absorbed energy in impact crash analysis. (3) The residual stress before spring back doesn't affect on the deform behavior mode and absorbed energy in impact carsh analysis. (4) The quantity of deference between the anslysis without all effects of hydro forming and that one with all effects of hydro forming depends on n value and total strain.

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