画像相関法による変位場測定とバーチャルフィールド法を用いた弾塑性材料特性の同定

抄録

　　　Elasto-plastic material properties are inversely identified from measured displacement fields using the virtual fields method. In order to identify the material properties from a few number of the displacement fields, total strain theory is used as a constitutive equation. The relations among the material properties, measured displacement fields, measured tractions, and virtual displacements are obtained from the principle of virtual work, and an over-determined set of equations is obtained by introducing virtual displacement fields. Then, they are solved by a least-square method to obtain material properties. The displacement fields of the specimen surface are obtained through the measurement using global digital image correlation. Then, the material property identification is implemented using a finite element model. The effectiveness of the proposed method is demonstrated by identifying the material properties of a pure aluminum specimen. Results show that the stress-strain relation after yielding can be evaluated from measured displacement fields by the proposed method.