Analyzing fracture properties of the 3D reconstructed model of porous rocks

The non-negligible fissures, cracks or pore structures, which are contained in rocks, have significant influences on their mechanical properties. In this paper, a novel method is developed to reconstruct a three-dimensional multiple phase rock model from the limited morphological information of Chongqing sandstone. Firstly, X-ray micro-CT experimental tests are applied to Chongqing sandstone to obtain the raw CT images and the mechanical parameters. Then, the two-point correlation function, lineal-path function and fractal function are combined to generate the reconstructed model. Next, the reconstructed model subjected to compressive loads is simulated by Finite Element-Smoothed Particle Hydrodynamics (FE-SPH) coupling method with a brittle model formulation. Finally, the initiation, propagation and coalescence of cracks are investigated during the numerical simulation. The topological and mechanical properties of the reconstructed model are carefully analyzed and compared with that of the reference model. The comparison of the numerical modeling results and the experimental data shows a good consistency. This indicates that the proposed method has the ability to predict macroscopic behaviors of rocks from limited experimental information.