デジタル画像相関法を用いた全視野変形?ひずみ測定の精度評価研究

摘要

Sub-pixel digital image correlation (Sub-DIC) method is effective for health monitoring of structures, because the Sub-DIC method can measure full-field deformation and strain distribution. However, the effect of analysis parameters of Sub-DIC method on measurement accuracy is not clarified. In this paper, we discussed the relation between the analysis parameters and the measurement accuracy of the Sub-DIC method. We demonstrated the analysis parameters such as a sub-set size, scan-step interval, and averaged point size on the standard deviation of measured deform and strain error distributions. Moreover, we found measurement accuracy is correlation related to the half width of spatial FFT spectrum of measured object and strain distribution. Finally, it is basically confirmed the measurement accuracy of Sub-DIC method depends on the central limit theorem.%昭和30年代から40年代の高度経済成長期において，rn社会的インフラの急速な需要の高まりから橋梁やダムrnなどの大型構造物が多く建造された．一方，高度経済成rn長期から40年以上が経過した近年，それらの構造物のrn老朽化が進み，その維持管理やリスク評価がより重要視rnされるようになっており，構造物の安全性や信頼性を評rn価する新しい手法である構造ヘルスモニタリングが提rn唱されている．