| 摘要 |
PURPOSE:To obtain with a high accuracy the effective information for maintenance by measuring the stress of a structure by an X-ray stress measuring method, combining it with a theoretical expression, and deriving a stress distribution and its secular change. CONSTITUTION:The stress in a measuring point 1 is measured by using a stress measuring method by X rays. In this case, by measuring the stress of the measuring point in a curve 2, at the operation start time point of a pipeline system being a structure, what is called a residual stress value by which a stress history received at the time of an assembly and at the time of welding, etc. is synthesized is obtained, when manufacturing a structure element. By referring to this value as a reference, thereafter, the stress measurement after the operation is executed at a necessary period interval in this measuring point 1, and by taking a difference to the reference value, the actual stress and its secular change are calculated. By combining this derived value and a theoretical stress calculating expression, the whole image of the stress distribution is obtained. By this whole image and its secular change, an external force which becomes its cause can be estimated further, and it becomes extremely effective as maintenance information. |
