2020 年 20 巻 3 号 p. 187-193
The Strain Visualization Device developed for structural health monitoring in the Operation and Maintenance of infrastructures can check the amount of strain with the naked eye. In addition, the amount of strain can be calculated with an accuracy of 10 με ± 10 με (2σ) by taking an image with a digital camera and analyzing the image. In applying the Strain Visualization Device to an actual structure, the effect of the shooting angle on the strain calculation accuracy was verified based on the shooting conditions in the field, and the shooting angle that secured the measurement accuracy was clarified. When applied to the strain measurement of a concrete bridge and photographed while paying attention to the shooting angle, the strain can be accurately measured, and the applicability of the strain visualization device to the strain measurement of the actual structure was verified.