Micro-seismic events within a mine have the potential to disturb planned daily operations as unpredictable events can lead to safety concerns. Mines are typically large-scale underground endeavours which cannot easily be modelled on the macro scale. One increasingly popular technique for simulating activity in mines is the material point method (MPM) which is a numerical algorithm designed for analysing

Cutting force prediction of the Stinger PDC cutter is a critically important work for the hybrid PDC bit design, which will directly affect the working stability and rock-breaking efficiency of drill bits. Thermal stress caused by drilling fluid cooling high temperature rock has significant influence on cutting force in geothermal drilling. However, to our best knowledge, the investigation of thermal

To study the effect of freeze–thaw weathering damage deterioration on the strength of Huashan granite, this paper conducted a freeze–thaw (FT) cycle test on Huashan granite at − 20 to 20 °C and 0–100 cycles. Thus, the basic physical parameters change law of Huashan granite after freeze–thaw weathering are obtained. The SHPB (Split Hopkinson Pressure Bar) device was used to perform uniaxial and confining

In this work we propose a method for mini-frac analysis via the direct numerical modeling for permeability and closure stress determination. The idea is to adjust the model parameters to match the simulated and field pressure curves by the virtue of the optimization algorithm to automatize the routine. To this end, the Planar 3D hydraulic fracturing model is improved to take into account the wellbore

Ultrasonic vibration-assisted rock breaking is a potentially effective technique to accelerate hard rock drilling processes. Fatigue damage is a primary factor that governs rock fragmentation subject to ultrasonic vibration, and when such damage accumulates to a critical level via crack initiation and propagation, macro-damage (e.g., macro-cracks) will occur. To date, however, the specific fatigue

Tunneling in karstic geology confronts numerous challenges due to unpredictable occurrence of voids. The current approach of karstic void risk assessment is qualitative or semi-quantitative and lacks consideration of the spatial variability and distribution of voids. This often influences the pricing strategies, and design and construction activities on tunnel projects. This paper presents a geostatistical

The investigation of localized deformation in rocks at the laboratory scale can yield valuable insights into the internal structures and mechanisms of shear zones and compaction bands that impact the permeability characterization and failure mechanisms of rocks. Combined with high-resolution X-ray computed tomography and in situ loading, the digital volume correlation (DVC) technique is an effective

Underground quarrying is rarely adopted for granite extraction due to the difficulties in the implementation of traditional technologies (drilling and explosive). As alternative to drilling and explosive, the combination of diamond wire and water jet seems to be the most promising available technology. The cutting performance achievable with the water jet technology depends on the operative parameters

Permeability measurements were made on sandstone during confined Brazilian strength tests. The test involves 50 mm diameter disk-shaped, jacketed samples that are subjected to confining stresses while they are diametrically loaded. Specially designed end caps allow for concurrent gas flow measurements. The test configuration allows for the samples to be subjected to a range of stresses, with the confining

Both the limit analysis and the limit equilibrium approach require the formulation of a failure criterion in terms of components of stress vector acting on a potential failure plane. For applications in Rock Mechanics, the generalized Hoek–Brown (GHB) criterion is commonly used, for which no analytical form of the Mohr failure envelope is, in general, available. In this work, a new approximation of

A dual-support smoothed particle hydrodynamics (DS-SPH) method is developed to quantify explosion-generated crack densities within granitic rock masses in field-scale computational domains. In DS-SPH framework, coupled Eulerian total Lagrangian formulations, along with interface treatment between solid and inviscid fluid particles are fully considered. A new momentum equation formulation for interface

Rockfall is a natural hazard that needs to be rigorously managed along all the major road and railways transport networks by identifying the most appropriate mitigation measures. There has been significant progress in rockfall modelling and rockfall protection systems in recent years but there remains one aspect that is not very well understood and quite challenging to account for in the design of

A correction to this paper has been published: https://doi.org/10.1007/s00603-021-02492-1

Granite boulders are characteristic geomorphological structures formed in granitic terrains. Due to their formation process associated with typical spheroidal weathering phenomena, they tend to show more or less ellipsoidal shapes prone to instability, and they often lie on small contact surfaces. Analyzing the stability of these boulders is not a straightforward task. First, these boulders may topple

The deformation and permeability of coal are largely affected by the presence and distribution of natural fractures such as cleats and bedding planes with orthogonal and abutting characteristics, resulting in distinct hydromechanical responses to stress loading during coal mining processes. In this research, a two-dimensional (2D) fracture network is constructed based on a real coal cleat trace data

The crack initiation stress (CI), a threshold stress at which brittle rock starts to become damaged during compression, has been widely studied. It can be used to estimate the spalling strength of tunnels in brittle rock masses. Many methods based on stress–strain curves and acoustic emission data have been proposed to identify the CI, and these methods have good statistical consistency. In the present

The generalized Zhang–Zhu (GZZ) strength criterion has a high associated fitting accuracy for true triaxial test data. It makes direct use of the parameters of the Hoek–Brown criterion and has become one of the strength criteria recommended by the International Society for Rock Mechanics (ISRM). In this study, a new version of the GZZ criterion is developed by addressing the problems associated with

Shiveluch volcano (Kamchatka, Russia) is an active andesitic volcano with a history of explosive activity, dome extrusion, and structural collapse during the Holocene. The most recent major (> 1 km3) dome collapse occurred in November 1964, producing a ~ 1.5 km3 debris avalanche that traveled over 15 km from the vent and triggered a phreatic explosion followed by a voluminous (~ 0.8 km3) eruption of

In April 2013, Rio Tinto Kennecott Copper’s (RTKC) Bingham Canyon Mine experienced what is arguably the world’s largest ever in-pit slope failure. The failure initiated on the east wall of the mine, along major, continuous, low-strength bedding faults, which were the upper and lower contact of the Manefay hornfels bed. The failure comprised approximately 145 million tonnes of rock and waste dump material

The uniaxial compressive strength (UCS) is an important parameter for rock mass classification and rock engineering designs. This study proposes a novel method for predicting the UCS of rocks using X-ray computed tomography and convolutional neural networks. First, X-ray CT scanning was conducted on five mudstone specimens. The volume data characteristics of the different density compositions in rock

Understanding mechanical properties of organic rich shale is crucial for successful exploration and long-term production of hydrocarbons from unconventional reservoirs. Due to the organic matter and clay minerals interlaced with other silicate minerals, shale can be studied as a heterogeneous material. In this work, the average mineral compositions and elastic mechanical properties were first characterized

Volumetric expansion of water by 9% in saturated pores and cracks causes substantial frost deformation in rock masses. Frost deformation is an important index reflecting the frost resistance of rocks; however, water saturation has a great influence on the frost deformation characteristics. In this research, the frost strains and acoustic emission activities of red sandstone with different water saturations

Geophysical wave measurements have been used as a remote and non-destructive method to monitor the changes in the state of contact, stress, and deformation in rock joints. In recent studies, geophysical precursors were identified as distinct maxima and minima in the amplitude of transmitted and reflected ultrasonic waves propagating through synthetic rock joints prior to the shear failure. However

An experimental work is presented that aims to improve our understanding of water–rock reaction, under both neutral and acidic conditions, and its effects on the mechanical deterioration of sandstone in Chongqing, southwest China, where a lot of heritage rock statues are carved in the same strata. SCB tests were conducted to evaluate the weakening of fracture toughness of Chongqing sandstone after

Coalbed methane (CBM) reservoirs show unique stress responses due to the additional sorption-induced effect under subsurface in situ condition. An insight of dynamic stress evolution is important to CBM development and carbon sequestration in coals. In this study, the combined controls of geomechanical effect and sorption-induced effect were gained to determine in situ stress evolution and predict

The wide range of gypsum facies observed all over the world and the strong heterogeneity that may be present even within a single facies often cause an inhomogeneous mechanical response that, if neglected, may be particularly dangerous in the framework of underground excavations. In addition, gypsum is particularly sensible to the presence of water. The high relative humidity conditions often registered

Geothermal energy has been widely proposed as a potential renewable energy to replace traditional fossil fuel energy. Hot dry rock (HDR) reservoir which contains abundant geothermal energy widely distributes in China. The Gonghe Basin in Northwest China is chosen to develop the Chinese first HDR field operation project. HDR is a low-permeability, high temperature and hard granite without fluid. Developing

The hydromechanical properties of single self-propping fractures under stress are of fundamental interest for fractured-rock hydrology and a large number of geotechnical applications. This experimental study investigates fracture closure and hydraulic aperture changes of displaced tensile fractures, aligned tensile fractures, and saw-cut fractures for two types of sandstone (i.e., Flechtinger and Fontainebleau)

Dynamic analyses of jointed rock masses, such as slope stability evaluations, have been intensively studied in recent years; discontinuous deformation analysis (DDA) is one of the feasible methods in this field. To predict the failure mode, the kinematic energy, and the reaching distance after the collapse, the friction characteristics of the rock joints must be computed correctly. However, conventional

The sub-critical propagation and interaction of cracks are important factors affecting the cracking and creep behavior of rocks, especially under the long-term coupling effect of the geo-stress and groundwater. The multi-stepped triaxial creep tests were conducted by using the mortar specimen containing two connected cracks to investigate the time-dependent fracture and mechanical characteristics of

An Enhanced Geothermal System (EGS) can be thought of as an underground heat exchanger designed to extract geothermal energy. The performance of these systems can be improved by increasing permeability with hydraulic fracturing, following the same technique used for hydrocarbon reservoirs. To understand hydraulic fracturing, whether it is implemented in an EGS or in a hydrocarbon reservoir, it is important

In the Three Gorges Reservoir Area (TGRA) has frequently occurred a large number of landslides in the stratified rock slopes with typical saw-tooth rock discontinuities since its impoundment in 2003, in which the shear mechanical behaviors of the saw-tooth rock discontinuities have been explored by few scholars. In this study, the macro-meso shear mechanical behaviors of the rock discontinuities with

On 23rd July 2019, a catastrophic long-runout basalt landslide was triggered by a heavy rainfall in Shuicheng county, Guizhou, China. The sliding mass transformed into a debris avalanche during the runout process traveled approximately 1250 m with an elevation difference of 465 m and finally caused 52 casualties. To improve the ability of risk assessment of such a basalt long-runout landslide, scanning

Tunnel construction usually suffers some water-filled karst caves, which can change the stress and flow fields and bring about unpredictable engineering disasters. A typical form of water inrush disaster caused by combination of steep karst fissures and concealed karst cave is proposed in this paper. The mechanism of this water inrush disaster is studied from aspects of geology and hydro-mechanical

Sockets are often constructed into weak rock mass to improve their axial response to applied compressive or tensile loads. This paper first establishes two separate load test databases for the side and base resistances in in situ socket load tests in weak rocks. The databases include the rock socket geometry, rock socket load–displacement response and the rock mass properties. The paper then reviews

This paper outlines the development of a fracture height growth prediction model that uses the modified rock mechanical properties obtained from a combination of fluid flow and rock material property behavior and applies them during the calibration process to match actual treatment data resulting fracture height growth evolution and profile. The traditional fracture growth models are closely linked

This article discusses the scale dependence of the mode \(\mathrm {I}\) fracture toughness of rocks measured via the semi-circular bend (SCB) test. An extensive set of experiments is conducted to scrutinise the fracture toughness variations with size for three distinct rock types with radii ranging from 25 to 300 mm. The lengths of the fracture process zone (FPZ) for different sample sizes are measured

The mechanical behavior of the sandy facies of Opalinus Clay (OPA) was investigated in 42 triaxial tests performed on dry samples at unconsolidated, undrained conditions at confining pressures (pc) of 50–100 MPa, temperatures (T) between 25 and 200 °C and strain rates (\(\dot{\varepsilon }\)) of 1 × 10–3–5 × 10–6 s−1. Using a Paterson-type deformation apparatus, samples oriented at 0°, 45° and 90°

As a part of the earthquake ground motion, large velocity pulses are probably one of the important factors leading to serious rock structural damage and geological disasters. It is vitally important to identify the response characteristics of large-scale structures under near-field pulse-like ground motions for earthquake prevention and disaster reduction. In this study, the pulse parameters from the

Investigation of rock progressive damage under static confinement and strain rates facilitates the generation mechanism of natural fault damage zones. A triaxial Hopkinson bar apparatus is used to perform dynamic triaxial compression tests to examine the damage and degradation process of rocks subjected to multiple impacts. Dynamic mechanical properties are determined under a static triaxial pre-stress

Rock bridges have been the subject of considerable research since the 1970’s with a focus on developing methods to measure rock bridges and quantifying their role with respect to rock mass strength. In the literature, rock bridges are generally defined as a portion of intact rock separating discontinuity surfaces; however, whether a portion of intact rock resists failure and, therefore, represents

Resin anchoring promotes the development of high-strength cable bolts for underground rock support. However, the resin anchoring the cable bolt must be very effective in soft rock. Using conventional anchoring methods, the anchoring force provided by cable bolts in soft rock is low, and achieving high-strength support is difficult. Aiming to address these problems, this study developed a method to

The early understanding of the rock masses in which a mine will be constructed and operated is of fundamental importance and required for developing reliable designs. To assist such understanding, this contribution is focused on massive to moderately jointed rock mass domains, their behaviour under load, rock mass strength, assessment, and implications to some cave mine design elements. Since more

We present a numerical technique capable of handling evolving fractures in rocks triggered by coupled thermo-hydro-mechanical (THM) phenomena. The approach is formulated in the context of the finite-element method (FEM) and consists in introducing especial (high-aspect ratio) finite elements in-between the regular (bulk) finite elements. We called this method the mesh fragmentation technique (MFT)

Understanding the failure behaviour of rocks is very important for many engineering applications. While conceptual models to predict failure behaviour of rocks have been proposed, very few models exist to quantitatively predict the brittle–ductile characteristics of mudstones at high confining pressures. In this study, we performed triaxial compression tests at confining pressures up to 130 MPa on

As a representative non-interferometric optical technique, the digital image correlation (DIC) can provide full-field displacement and strain measurement for the deformed rocks. However, the standard DIC technique has a limitation in measuring the displacements at the discontinuity and cannot be directly used for identifying the crack mechanism. Thus, a new DIC-based method is proposed for automatically

In this study, a new approach based on DEM was developed to simulate the damage of water-rich rock after freeze–thaw cycles. In this way, water-rich rock samples at low temperatures were simplified as rock particles, ice particles, rock–rock contacts, rock–ice contacts, and ice–ice contacts. The volume of the ice particles changed as the temperature changed. The change characteristics were determined

Cemented paste backfill (CPB) has been widely used as local and regional underground support to reduce host rock wall closure in mined-out areas and also to reduce rockfall and rockburst incidents. However, analyzing the rock mass—CPB interactions in the first month after backfill placement must account for the CPB’s time-dependent strength, stiffness, and volume change characteristics during binder

Discontinuities with different joint wall strengths (DDJS) are very common in the Three Gorges reservoir area, P.R. China. Experimental results illustrate that the peak shear strength of DDJS is different from the discontinuities with identical joint wall strength (DIJS). However, few criteria are available in the literature to predict the peak shear strength of DDJS. In the present study, a new parameter

Blasting performance is influenced by mechanical and structural properties of the rock, on one side, and blast design parameters on the other. This paper describes a new methodology to assess rock mass quality from drill-monitoring data to guide blasting in open pit operations. Principal component analysis has been used to combine measurement while drilling (MWD) information from two drill rigs; corrections

Analysis of the failure mechanism of inclined coal pillars is one of the complicated issues. The wide variability of dip angles of inclined coal pillars makes it more complex. The asymmetric stress distribution and the tendency of shearing along the bedding planes make the inclined coal pillars to behave differently from the flat coal pillars. There is a need for in-depth investigation of the failure

Since the shale matrix has a very low permeability, the flow in the matrix is often transient flow. Hence, conventional reservoir simulators often do not accurately estimate the mass exchange between matrix and fractures. To evaluate the effect of water injection on oil recovery realistically, reservoir simulators need to incorporate the mass transport in the reservoir at different scales. These issues

The dynamic mechanical experiments were carried out on shales with the different bedding angles (θ = 0°, 30°, 45°, 60°, 90°) using the 50 mm split Hopkinson pressure bar (SHPB) test system with the thermo-mechanical coupling equipment. Firstly, the dynamic parameter of shales, such as the stress–strain curve, peak stress, peak strain, dynamic elastic modulus, and energy partition were acquired. The

Uniaxial compressive strength (UCS) is the most fundamental physico–mechanical parameter used for any rock mass classification in geotechnical and geological engineering. However, determining UCS is a very tough, expensive, time consuming and destructive method and requires experienced workers. On the other hand, P-wave velocity (VP) determination is cheap, precise, non-destructive and easy. There

We discuss the baric and temperature dependences of the effective thermal conductivity of rocks (including sandstones) naturally occurring in the earth’s crust. We present the results of our experimental studies of the effective thermal conductivity of natural sandstone under hydrostatic pressure (up to 400 MPa) in the temperature range (273–523 K), performed by the absolute steady-state method of

Rock brittleness is an important index evaluating geotechnical stability and failure mode, and it is also influenced by pore fluid pressure, especially in deep underground mining. To evaluate the brittleness from stress–strain curves of uniaxial compression, uniaxial compressive tests were carried out on water-pressurized coal samples, and a new energetic brittleness index was proposed. The saturated

The greatest challenges of rigorously modeling coupled hydro-mechanical processes in fractured rocks at different scales are associated with computational geometry. In addition, selections of continuous or discontinuous models, physical laws, and coupling priorities at different scales based on different geometric features determine the applicability of a numerical model for a certain type of problem

In this study, numerical simulations of the behaviour of large-size sandstone specimens exposed to wood crib fires were conducted. The developed numerical model, which innovatively considers the reversible quartz expansion behaviour during heating–cooling cycles, can replicate the temperature distributions, cracking behaviours, and strength variations of sandstone samples under various thermal loads

Fracture initiation and propagation from a wellbore within a rock formation exhibit nonlinear and inelastic behaviors. When the rock material undergoes plastic deformation prior to failure, the classical Griffith theory is no longer valid. In this study, a variational phase-field approach is applied to model the inelastic behavior of granite rock in a punch through shear test. The rock failure and

It is very important and effective to characterize the failure mechanism of coal and rock materials from the perspective of energy. Energy dissipation and release are important causes of rock mass failure. To qualitatively and quantitatively characterize the energy evolution process of gas-bearing coal and the energy evolution mechanisms of coal and gas outburst, experimental studies were conducted