  Digital Volume Correlation (DVC) is widely used for the analysis of
three-dimensional displacement and strain fields based on CT scans. However,
the applicability of DVC methods is limited when it comes to geomaterials: CT
speckles are directly correlated with the material's microstructure, and the
speckle structure cannot be artificially altered, with generally poor speckle
quality. Additionally, most geomaterials exhibit elastoplastic properties and
will undergo complex-large deformations under external loading, sometimes
leading to strain localization phenomena. These factors contribute to
inaccuracies in the displacement field obtained through DVC, and at present,
there is a shortage of correction methods and accuracy assessment techniques
for the displacement field. If the accuracy of the DVC displacement field is
sufficiently high, the gray residue of the two volume images before and after
deformation should be minimal, utilizing this characteristic to develop a
correction method for the displacement field is feasible. The proposed
self-correcting strategy of the DVC displacement field based on image matching,
which from the experimental measurement error. We demonstrated the
effectiveness of the proposed method by CT triaxial tests of granite residual
soil. Without adding other parameters or adjusting the original parameters of
DVC, the gray residue showed that the proposed method can effectively improve
the accuracy of the displacement field. Additionally, the accuracy evaluation
method can reasonably estimate the accuracy of the displacement field. The
proposed method can effectively improve the accuracy of DVC three-dimensional
displacement field for the state of speckles with poor quality and
complex-large deformation.
