The failure of granite is a complex micromechanical process. The formation, growth, and accumulation of microcracks lead to strain localization, which then causes macro-fractures (Benson et al. 2008; Lockner et al. 1991).The progressive degradation of integrity during failure and the intrinsic microstructure defects together make the granite fracture mechanism …

The initial stage, the pore fracture compaction stage (OA), is succeeded by the elastic deformation stage and the stable micro-elastic fracture development stage (AB). In this process, the stress–strain curves align in a straight line. Subsequently, plastic deformation (BC) manifests with the onset and growth of micro-cracks in the sample.

The resulting memoir reflects the debate of the time over the contrasting ideas about the formation of granite by the nebulous process of "granitization" or the simple process of crystallization from a melt. ... In deformation experiments on melt-bearing rocks, the proportion of melt-bearing grain boundaries generally increases as the ...

The energy evolution characteristics of granite specimens from a quarry in Miluo city (China) were studied in the triaxial deformation and failure process of the rocks.

The abovementioned studies indicate that grain size is a crucial factor influencing the mechanical behavior of granite. The failure of rock materials is a gradual process that involves microcrack closure, initiation, propagation, a decrease in cohesion between grains with the microcrack evolution, and ultimately the formation of macroscopic damage (Eberhardt et al., …

Granite deformation and permeability variations under the compression-seepage condition are analyzed. The deformation process is divided into five stages based on the measurements of properties such as rock volume, stress–strain relationship, and AE counts in compressive tests. Besides, the permeability variation is observed to be better ...

This study aimed to investigate the degradation laws of deformation parameters, the evolution characteristics of energy dissipation, and the acoustic emission response of deep granite through triaxial cyclic loading and unloading tests.

This study conducts experiments on granite to investigate the effects of temperature gradients on pore structure and rupture propagation under different media, specifically liquid nitrogen and air. The pore structures and granite's transverse relaxation time (T 2) are …

Compression-shear fracturing experiments on thermally-treated granites are performed. Thermal effects on physical properties and response of AEs, EPs and strain fields are analyzed. Damage evolution and precursors are explored quantitively by multiparameter analysis.

Via these tests, the deformation characteristics of granite at different confining pressure unloading rates were explored. The research results showed that the granite specimens were more easily damaged at an intermediate unloading rate than at a high or low unloading rate.

The deformation field evolution process of the sample is obtained by processing the speckle image of the sample surface. Considering 0 in figure 8 as a reference point, the evolution law of the displacement and deformation field of the rock sample after pre-damage under high confining pressure cyclic load is observed at points 1, 2, 3 and 4.

Investigation of Granite Deformation Process under Axial Load Using LSTM-Based Architectures. Yalei Wang 1, Jinming Xu 1,2,*, Mostafa Asadizadeh 3, Chuanjiang Zhong 4, Xuejie Tao 1. 1 Department of Civil Engineering, Shanghai University, Shanghai, 200444, China 2 Institue for the Conservation of Cultural Heritage, Shanghai University, Shanghai, 200444, China 3 …

When the axial load (σ 1) reached 80% of its axial peak stress (σ p), the unloading and reloading process was carried out per 0.2–0.4 mm increments in lateral deformation. The unloading rate was remained at 1 kN/s, and the reloading process was controlled by the lateral deformation with a rate of 0.3 mm/min.

The wetting-induced deformation process presented significant time-dependent characteristics with stable creep. A new time-varying effect model was established based on the experimental results, which enabled an accurate simulation of the wetting deformation of the rock mass through a comparison with the experimental results. ... Ruan B (2020 ...

The deformation and fracture of rocks during the loading process often involve four stages: compaction, elastic deformation, plastic deformation, and unstable failure. In terms of the overall trend, the variation patterns of the AE and EMR counts tended to synchronize during the deformation and fracture processes of granite under load.

During the deformation and fracturing process of loaded rock, the phenomenon of releasing strain energy in the form of elastic waves is known as acoustic emission (AE) [11], [12].The AE technology is a valuable tool for investigating rock failure mechanisms and predicting rock dynamical disasters [13], [14], [15], which has been a well-established technology that …

A particle-based discrete element model combined with digital image processing to take into account the grain geometry and size distribution is used to investigate the mechanical and microcracking behavior of Beishan granite (BG), a typical crystalline rock potential for nuclear waste disposal in China. First, the procedure to construct a digital image-based grain-based …

emission signals of granite in ultra-deep gold mine. Abstract: To study the crack evolution law and failure precursory characteristics of deep granite rocks in the process of deformation and failure under high confining pressure, granite samples obtained from a depth of 1150 m are tested using a TAW-2000 triaxial hydraulic servo testing ...

Above 400 °C, granite's deformation gradually increases, demonstrating typical plastic failure characteristics. Higher temperatures accentuate the post-peak plastic behaviour.

The uniaxial stress–strain curve for the group D granite is shown in Fig. 4, and the uniaxial peak compressive strength is 164.20 MPa, 162.57 MPa, and 167.87 MPa, respectively.The impact energy index of granite is calculated using Eq. (1) [27]: (1) w ef = E 1 E 2 where E 1 is the deformation energy stored before the peak value, E 2 is the deformation …

mechanical properties of granite, i.e. the failure process and deformation, are closely related to its microstructure, including mineral composition and distribution, and grain

The fracture process zone presents as a narrow band whereas it occurs and develops prior to visible cracks. Brazilian test setup for Harcourt granite. Synchrotron set-up.

The deformation and damage process of the rock is essentially the process of fracture emergence, extension, interaction and penetration. The complex fracture forms endowed in the rock mass will change the force state of the rock mass, which further affects the damage form and destabilization process of the rock mass.

Abstract. Read online. To study the crack evolution law and failure precursory characteristics of deep granite rocks in the process of deformation and failure under high confining pressure, granite samples obtained from a depth of 1150 m are tested using a TAW-2000 triaxial hydraulic servo testing machine and a PCI-II acoustic emission monitoring system.

The emplacement of granitic magma within the continental crust marks the final stage in the granite forming process. Emplacement is defined here as the switch from upward to horizontal flow, and ...

This allows us to make more, and larger pieces from a single block of stone, improving our lead time and efficiency. This spirit of continuous improvement carries on at our Steinechnik facility as well. Recently Wenzel has invested in a new 5 Axis vertical mill, to streamline the manufacturing process, and reduce the handling of the stone.

IntroductionExperimental observations indicate that under compression, the failure process of brittle rocks consists of several stages: crack closure, elastic deformation, crack initiation, crack ...

Rheological deformation and failure laws of boreholes in granite under thermo-mechanical coupling and its application in deep hole drilling of hot dry rock for geothermal energy exploitation

The deformation of rock mass is not a simple material deformation but is composed of material deformation and structural deformation. ... Crack propagation process in double-flawed granite under ...

Based on three‐dimensional digital image correlation (3D‐DIC) technique, the deformation behavior, damage and fracture characteristics of the granite specimens have been tested and observed by ...