3D reconstruction of granite mesostructure based on electron backscatter diffraction tests

• A 3D reconstruction method for granite mesostructure is proposed considering morphology and distribution of various mineral particles. • The EBSD testing results are first introduced in mesostructure modeling of granite. • Assumptions and procedures for converting 2D geometric information of minerals making up granite into 3D information are proposed. The reconstruction of 3D mesostructures of rocks are essential for accurately predicting the rock mechanical behavior and revealing the deformation and failure mechanism of rocks. The electron backscatter diffraction (EBSD) testing results are first introduced in mesostructure modeling of rock, and a 3D mesostructure modeling method for granite is proposed in this article considering types and geometries of multiple minerals. Firstly, the EBSD tests have been conducted on granite slices. Subsequently, based on the extraction and analysis of the types and geometric characteristics of mineral particles in the EBSD test result images, ellipsoids are used as the intermediate carriers for 3D modeling of mineral particles. Based on corresponding assumptions, the geometric characteristics of mineral particles are transformed from 2D information to 3D information, ultimately achieving the reconstruction of the 3D model for the granite sample. The error analysis results show that the target values and actual values of the volume proportions of various minerals in the 3D reconstruction model are generally consistent, and the absolute relative error ranges from 2.17% to 11.83%, verifying the rationality of the 3D reconstruction model. The proposed method overcomes the limitation of the large gap between the modeling results of random modeling methods and the actual mesostructures of rocks. On the other hand, it overcomes the disadvantages of heavy slicing workload in FIB-SEM and other methods, with high modeling efficiency and low time consumption as well as wide applicability and generalizability in different types of rocks.