Numerical Analysis of Rock Deformation Evolution Regarding Microcracking Process

Abstract

The failure and deformation characteristics of rock under stress are controlled by microcracking process. There are various laboratory and analytical methods for understanding the evolution of this phenomenon. In this study, the applicability of the numerical modeling technique for detecting the microcracking process is investigated as an alternative method among the other techniques. Macro mechanical parameters derived from the laboratory tests, performed on three different rock types such as ignimbrite, marble, and diabase are used in the calibration of the numerical rock models which are generated based on the discrete element method (DEM). According to the results, model predictions and laboratory measurements are in good agreement that verifying cracking analysis can be performed as being representative of the rock domain in the numerical platform. During the simulations of laboratory tests, the initiation (σci) and propagation (σcd) stress thresholds of microcracking are determined in the model samples under compressive loading. These stress levels are σci = 25 MPa and σcd = 37 MPa for ignimbrite, σci = 21 MPa and σcd = 30 MPa for marble, and σci = 38 MPa and σcd = 55 MPa for diabase, respectively. Microcracking in all rock models is controlled by extensional mechanisms, and all rock types present brittle behavior. Overall, our insights show that the numerical modeling technique based on DEM can be used reliably as an alternative methodology to the other techniques for the investigation of the microcracking process in rocks. © 2023, Hacettepe Universitesi Yerbilmleri. All rights reserved.