...) approach such as UDEC-Voronoi has been widely used to simulate the complex brittle rock fracturing process and predict the shape of the excavation damage zone (EDZ) developed around underground openings. To realistically predict the EDZ shape, the BBM must be calibrated to accurately replicate...

... specimens. Results on brittle rocks demonstrate the performance and advantages of the proposed methodology in controlling the cracking process with clear snapback in the load-displacement response. Overall, the results and discussion in this study highlight the significance of the AUSBIT methodology...

... brittleness indices recognized granite as the most brittle rock which was in a good agreement with the data obtained from the high-speed imaging. 1. Introduction The brittleness is one of the most important mechanical properties of materials and was firstly defined as the lack of ductility or the lack...

... ABSTRACT: Time-dependent deformation occurs in rock pillars, and it affects the stability of the pillars and excavations. In this paper, time-dependent deformation behaviors of brittle rock pillars are studied using a grain-based time-to-failure model (GBM-TtoF). First, time-dependent...

... ABSTRACT: This work presents a thermodynamic-consistent directional damage theory that considers the kinetics of microcrack growth for brittle rocks. The novelty of the theory is that the distribution density of microcracks is directly incorporated at the continuum level through the notion...

..., in general, tend to overestimate this critical strength parameter in hard rocks. Alternative approaches are therefore to be developed that are more accurate, reliable, robust and more suitable to hard and brittle rock-like solids. This paper, first, reviews some of the widely accepted testing techniques...

... ABSTRACT: Understanding time-dependent deformation behavior of brittle rock is of great importance for designing rock structures for long-term stability. This research presents a new method to simulate time-dependent failure of brittle rock using the grain-based model (GBM) in PFC. Time...

... ABSTRACT: To explore the stress relaxation related strength and failure character of brittle rock, experimental investigations that consist of various kinds of loading paths are conducted on the granite material. For brittle rock material, the relaxation and creep behavior is related...

... the crack initiation criterion in brittle rocks containing minute pores of different shapes under biaxial compression and pore pressure elevation. Analytical results reveal that the pore aspect ratio has a significant impact on the crack initiation near the pore tip. In addition, the combined effect...

...-based support design. Reservoir Characterization dilation lac du bonnet pink granite plastic dilation model dilation mobilization brittle rock Upstream Oil & Gas compression test increment potential function parametrization dilation characteristic metals & mining stress...

... of the disc, where the induced tensile stress is the maximum. However, when applied to disc specimens of harder, stiffer and brittle rocks, secondary shear fractures often interfere adversely with the diametrical (characteristic) tensile crack in the Brazilian test. To prevent such undesirable shear cracking...

... laboratory tests and previous researches on several kinds of brittle rocks. The tensile strengths were determined from Brazilian disc (BD) specimens, and the mode-I fracture toughness data were determined from cracked chevron-notched Brazilian disc (CCNBD) specimens, as suggested by the International Society...

.... It is generally accepted that the time-dependent non- linear deformation and fracturing process that evolve in brittle rocks are mainly dominated by the progressive accumulation of subcritical damage originating from the propagation and coalescence of microcracks due to stress corrosion occurring at crack tips [1...

... Characterization crystalline rock specimen rock type Forsmark granite Upstream Oil & Gas AE event threshold granite Indiana limestone propagation acoustic emission technique initiation fracture crack initiation rock specimen elastic strain energy crack damage threshold brittle rock Sentry...

... Abstract The objective of this paper is to investigate the failure process of brittle rock in particle scale under compression with different confining pressures. Three-dimensional discrete element code PFC3D is adopted to perform the numerical simulations where intact rock is represented...

... coefficient brittle rock initiation threshold crack initiation elastic stage Abstract: In analyzing intact rock strength, an important factor is heterogeneity. At the grain-scale, intact crystalline rock consists of a variety of mineral grains of different sizes and shapes. These features give...

... platen failed zone rectangular tunnel rockburst tunnel shape UC test specimen finite difference method circular tunnel Magnitude rockburst manifestation unstable failure rock failure brittle rock strain rate rockmass boundary brittleness Indicator Abstract...

... Abstract: Fabric-guided micro-fracturing phenomenon in brittle rock and its effect on crack damage thresholds remains a subject that challenges researchers. Anisotropy of brittle rocks in terms of crack initiation (CI) and crack propagation (CD) thresholds plays a significant role...

... ABSTRACT: Brittle spalling is the failure mechanism that is commonly observed in the walls of underground excavations in rocks with high ratio of compressive to tensile strength (brittle rock). Extensile crack damage that is controlling spalling in brittle rock is rarely capable of leading...

... on the brittle and ductile rock failure mechanisms and claims that the slope change at the LOP may indicate the transition between the brittle rock failure and ductile rock failure. In this circumstance, the LOP is equal to the breakdown pressure. 1. INTRODUCTION In wellbore stability studies, the primary...