Understanding the behavior of rockmasses during the entirety of the deformation process is critical for safe and effective excavation design. Recent studies have researched the stress-strain behavior of rockmasses with a focus on the post-yield region by using laboratory specimens as potential rockmass analogs. However, such tests are time-consuming and sample preparation can be difficult. So far, tests have only been conducted on a limited variety of specimens, so it is difficult to generalize these results to other rockmass conditions. To overcome these limitations, numerical modeling techniques can be applied. This study presents the development and calibration of a Bonded Block Model (BBM) for simulated laboratory testing of Blanco Mera granite. A voronoi grain structure was generated in Neper for the BBM, since it allowed for incorporation of variable grain sizes for the different constituent minerals within Blanco Mera granite. After calibration was completed using UDEC, the model was able to match multiple attributes observed in the laboratory experiments including elastic moduli, pre-peak damage thresholds, and peak strength under various confinement conditions. The ability to match this data has further confirmed the validity of the numerical model in addition to providing a basis for which numerical testing of samples under other conditions can be performed. In the future, this study will be expanded to include jointed samples to compare with published laboratory data for artificially jointed Blanco Mera granite specimens.

1. INTRODUCTION

Numerous studies have analyzed the effect of natural jointing on rockmasses (Ramamurthy and Arora, 1994; Hoek and Brown, 1997; Alejano and Alonso, 2005). Specifically, multiple researchers have studied Blanco Mera granite (Arzua and Alejano, 2013; Arzua et al., 2014; Alejano et al., 2017; Walton et al., 2018) and analyzed differences in the stress-strain behavior of jointed rock samples, which act as rockmass analogs. The behavior of samples with two distinct jointing patterns have been compared to intact behavior throughout these studies.

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