International Journal of Rock Mechanics and Mining Sciences最新文献

{"title":"A multi-processes phase-field model for CO2 phase change fracturing","authors":"ZiHan Zhang ,&nbsp;Hao Yu ,&nbsp;Bo Li ,&nbsp;Wei Cheng ,&nbsp;JiaPing Tao ,&nbsp;SiWei Meng ,&nbsp;He Liu ,&nbsp;HengAn Wu","doi":"10.1016/j.ijrmms.2025.106363","DOIUrl":"10.1016/j.ijrmms.2025.106363","url":null,"abstract":"<div><div>Carbon dioxide (CO₂) phase change fracturing technology generates a massive amount of energy through the phase change of injected fluid in a short period, where the fluid is extruded into the rock formation to drive the fracture propagation. Apart from the rock inertia effect during fracturing, fracture instability could be seen at the crack tip due to a significant phase changing fluid infiltration, which is often ignored in previous models. This work develops a multi-processes phase-field framework for CO₂ phase change fracturing in rock formations. The phase changing effect for non-equilibrium multi-phase flow is coupled by modifying mass and energy conservation equations where the Vesovic model is utilized to accurately capture the transport properties of CO₂ and the fluid infiltration. G-criterion correlated to the pore pressure gradient is introduced to describe rock strength degeneration caused by fluid infiltration, which destabilizes the fracture propagation. The model is validated against the experimental and theoretical results. Four different fracturing methods (water-based fracturing, CO₂ fracturing, blasting fracturing, and CO₂ phase change fracturing) are carefully analyzed, indicating that CO₂ phase change fracturing generates multi-level branches while increasing the stimulated reservoir volume compared with water-based/CO₂ fracturing. Different from blasting fracturing, the branching in CO₂ phase change fracturing is mode II fracture caused by the fluid infiltration with weaker inertia effects rather than mode I dynamic fracture. The influences of different formation parameters on fracturing behaviors are further discussed, which provides theoretical guidance for engineering applications of CO₂ phase change fracturing technology.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"198 ","pages":"Article 106363"},"PeriodicalIF":7.5,"publicationDate":"2025-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145731628","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Normal deformability of rough rock joints – a predictive analytical model based on Persson's theory of contact","authors":"Yue Cui ,&nbsp;Yingchun Li ,&nbsp;Yang Xu","doi":"10.1016/j.ijrmms.2025.106365","DOIUrl":"10.1016/j.ijrmms.2025.106365","url":null,"abstract":"<div><div>Prediction of the normal deformation of natural rock joints has long been a burning and thorny issue covering several important fields including rock mechanics, geophysics and hydrogeology. A key barrier preventing our accurate quantification towards the joint normal deformability lies in the complex interaction between two random, multi-scale rough surfaces. Classic multi-asperity contact models (e.g., Greenwood and Williamson, 1966) are based on statistical distribution with Hertz contact theory and simply assumed single-scale contacting asperities of identical shape and thus overlooked mechanical interactions of random asperities spanning a wide spectrum of geometrical scales. Here we first applied Persson's theory (Persson, 2001a), a multi-scale rough surface contact model based on the stochastic process theory, to derive the analytical normal stress-closure relationship of rough-walled joints. The core strengths of this theory include (1) quantitative description of geometric properties of multi-scale roughness via power spectral density; (2) stochastic interpretation of evolutions of roughness contact and commensurate local contact pressure; (3) stochastic modeling of asperity interaction across multiple scales; and (4) derivation of the global normal stress-deformation relationship driven by the conservation of elastic energy stored over the contact area variation of deformed multi-scale roughness. Comparisons between analytical solutions and experimental measurements on eight pairs of rough rock joints demonstrated the robust performance of Persson's theory in predicting the normal stress-closure relationship of both matched and mismatched joint walls. Our study may offer an alternative paradigm for pertinent academic communities to interpret the empirical semi-logarithmic rule and multi-scale nature of the normal deformability of natural rock joints.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"198 ","pages":"Article 106365"},"PeriodicalIF":7.5,"publicationDate":"2025-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145731627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Failure behaviour simulation of transversely isotropic rocks considering realistic grain structure and bedding plane morphology","authors":"Renjie Wu ,&nbsp;Haibo Li ,&nbsp;Guorui Feng ,&nbsp;Yuxia Guo ,&nbsp;Chong Yu","doi":"10.1016/j.ijrmms.2025.106369","DOIUrl":"10.1016/j.ijrmms.2025.106369","url":null,"abstract":"<div><div>Constructing numerical models based on real microstructures is fundamental for accurately capturing rock failure behaviour. Herein, a novel grain-based model with transverse isotropy (GBM-T) based on the bonded particle method is proposed to explore the intrinsic mechanism underlying the failure of transversely isotropic rocks at the grain scale. First, the mineral composition, grain size and grain shape of transversely isotropic gneiss are obtained, and the uniaxial compressive strength and Young's modulus of gneiss with different bedding plane angles are measured. A transformation algorithm is then applied to construct GBM-T, which considers realistic grain shape and complex bedding plane morphology. The mechanisms of different failure modes are analysed from the view of mineral-scale. Results indicate that the damage of gneiss with different bedding angles can be effectively reproduced using GBM-T. The deformation characteristics of rocks with horizontal bedding planes are dominated by intragranular tensile cracks, while tensile cracks propagating along grain boundaries have a significant impact on the fracture features of rocks with vertical bedding planes. Owing to the widespread occurrence of transversely isotropic rocks on the Earth's surface, GBM-T is expected to be applicable in the engineering fields, such as mining, tunnelling, shale gas extraction, salt cavern storage and slope protection, etc.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"198 ","pages":"Article 106369"},"PeriodicalIF":7.5,"publicationDate":"2025-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145689651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the thermal effects of mechanical behavior in the Callovo-Oxfordian claystone","authors":"Chuanrui Wang ,&nbsp;Shouyi Xie ,&nbsp;Jian-Fu Shao ,&nbsp;Minh-Ngoc Vu ,&nbsp;Christophe de Lesquen","doi":"10.1016/j.ijrmms.2025.106367","DOIUrl":"10.1016/j.ijrmms.2025.106367","url":null,"abstract":"<div><div>The Callovo-Oxfordian (COx) claystone is investigated as host rock in the French project Cigeo for geological disposal of radioactive waste. Temperature rise due to heat emitted by radioactive waste is an important process to be considered. It is crucial to characterize effects of temperature change on the mechanical behavior of host rock. Despite previous studies, the issue is still open. This work presents a complementary study by performing a new series of triaxial compression tests. Six different values of temperature are considered ranging from 20 °C to 90 °C. The tests are performed under three different confining pressures. Elastic properties upon unloading–reloading paths and peak deviatoric stresses are evaluated for each test. It is found that the peak deviatoric stress of COx claystone is more affected by the temperature rise than the elastic properties. Scatters of experimental data are also investigated by comparing several tests performed under the same loading conditions. Finally, the thermal effects on the failure strength are evaluated by using a micromechanics-based criterion.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"198 ","pages":"Article 106367"},"PeriodicalIF":7.5,"publicationDate":"2025-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145665696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A combined viscoplastic damage-phase field model for rock fracture under dynamic loading","authors":"Timo Saksala ,&nbsp;Mahmood Jabareen","doi":"10.1016/j.ijrmms.2025.106364","DOIUrl":"10.1016/j.ijrmms.2025.106364","url":null,"abstract":"<div><div>The phase field method captures tensile (mode I) fracturing of brittle materials but has serious challenges in uniaxial compression of heterogeneous materials like rock and concrete. In this paper, we mend this drawback by combining a phase field model for mode I fracture with a viscoplastic damage model to capture the shear banding in uniaxial compression of rock. In the present phase field formulation, the mode I fracture is driven by Rankine type of crack driving force, while the Mohr–Coulomb criterion is employed in the viscoplastic damage part of the model to capture the compressive/shear failure. As the model is designed for transient dynamic problems, strain rate sensitivity of rock is accommodated, here by a linear viscous term in both the phase field and viscoplastic damage parts. The viscoplastic part is cast in the consistency format. The phase field variable and the damage variable operate, respectively, on the positive and negative parts of the principal stress returned to the (Mohr–Coulomb) yield surface. The performance of the model is demonstrated in uniaxial tension and compression tests. Finally, the dynamic Brazilian disc test and punch-through shear tests are simulated for further validation. The model captures the strain rate sensitive direct and indirect tensile strength as well as the correct failure modes in these tests.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"197 ","pages":"Article 106364"},"PeriodicalIF":7.5,"publicationDate":"2025-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145657714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating the risk of induced seismicity in nuclear waste disposal","authors":"Bruce Gee ,&nbsp;Mengsu Hu ,&nbsp;Michael Manga","doi":"10.1016/j.ijrmms.2025.106359","DOIUrl":"10.1016/j.ijrmms.2025.106359","url":null,"abstract":"<div><div>Deep geologic repositories are a proposed solution to safely dispose of nuclear waste at the end its useful life. As the contents decay, heat is released into the surrounding subsurface, creating stress and driving heat and fluid transport. While it is not expected that a repository would be placed in an area with recent geologic activity, an induced seismic event could have significant detrimental effects on the integrity of the repository and safety of the public. Here we examine the frictional stability of both locked and aseismic creeping faults subjected to nuclear waste decay heating for both granite and argillite rock masses. The stress in the rock mass is evaluated numerically using a volumetric thermo-poro-elastic response and a deviatoric visco-elastic Burgers model. Thermally-dependent rate and state friction models are used to evaluate the frictional stability. The risk of induced seismicity is generally low, as only small perturbations to the factor of safety are induced by the heating. Both rock types have advantages, as the higher friction of granites creates greater factors of safety, while the creep of argillite reduces the thermal stresses. The in-situ conditions have the greatest effect on the risk of induced seismicity, and higher mean in-situ stresses and hydrostatic conditions lower the risks of inducing a seismic event. Faults undergoing aseismic creep are likely to experience an increase in their creep rate but appear unlikely to experience rupture. This analysis provides guidance in site selection to minimize the risk of induced seismicity when building a deep geologic repository.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"197 ","pages":"Article 106359"},"PeriodicalIF":7.5,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145651077","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of stress heterogeneity on shear behavior of rock discontinuities in laboratory experiments: New insights from numerical simulations","authors":"Shupeng Chai ,&nbsp;Yuan Zou ,&nbsp;Huanyu Wu ,&nbsp;Mohammadreza Akbariforouz ,&nbsp;Boyang Su ,&nbsp;Giovanni Grasselli ,&nbsp;Derek Elsworth ,&nbsp;Yossef H. Hatzor ,&nbsp;Qi Zhao","doi":"10.1016/j.ijrmms.2025.106358","DOIUrl":"10.1016/j.ijrmms.2025.106358","url":null,"abstract":"<div><div>Laboratory shear tests are widely used to investigate the evolution of first and second-order frictional behavior and rupture nucleation on rock discontinuities. Average stress across the sample, instead of spatial stress distributions, is typically assumed in analysis. We provide a thorough numerical investigation of eight common laboratory shear test configurations, considering a linear velocity-weakening friction law on a planar sliding surface, to quantify the temporal and spatial nonuniformity of stress both before shear and during stick-slip cycles. Our results indicate that non-uniform stress distribution resulting from the test configuration exists in all laboratory shear tests, with stress concentration occurring at the edges of the shear plane, while the stress in the central portion of laboratory faults remains almost uniform. Stress heterogeneity is more pronounced in direct shear than in inclined and rotary shear configurations. During stick-slip cycles, the local shear stress significantly dropped as the rupture front propagated through, resulting in a more uniform stress distribution in the slip phase than in the stick phase. Stress concentration near the sample edge governs the rupture process and the resulting localization of damage. These findings highlight the importance of considering stress heterogeneity in laboratory investigations of damage evaluation on rock discontinuities. We suggest that test configuration-related stress heterogeneity should be distinguished from surface roughness-induced stress heterogeneity, and utilizing average stress may lead to misinterpretation of the rupture dynamics and damage patterns. Our results provide a guide on quantitative analysis of the shear behavior of rock discontinuities, considering stress heterogeneity in laboratory experiments.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"197 ","pages":"Article 106358"},"PeriodicalIF":7.5,"publicationDate":"2025-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145614045","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"FisTopNet: A deep learning framework for automated estimation of evolving rock fracture network topology from image sequences","authors":"Liangchen Zhao ,&nbsp;Yixin Zhao ,&nbsp;Xinze Li ,&nbsp;Zhe Yang ,&nbsp;Jihong Guo ,&nbsp;Hua Bian","doi":"10.1016/j.ijrmms.2025.106361","DOIUrl":"10.1016/j.ijrmms.2025.106361","url":null,"abstract":"<div><div>Rock fracture networks have a major impact on rock mass mechanical behavior, and their accurate characterization is important for various engineering disciplines. However, traditional manual topological analysis of these networks suffers from subjectivity and inefficiency, limiting its application, particularly for dynamic fracture processes. This study bridges this fundamental gap by introducing FisTopNet, a novel deep learning approach for direct and automated estimation of fracture network topology from image sequences. FisTopNet employs a multi-task learning architecture to perform semantic segmentation of fractures, fracture edge detection, and the extraction of the fracture topological graph, including its constituent nodes and connecting branches. Proposed FisTopNet utilizes the temporal information in the image sequences and takes into account the dynamic evolution of the fracture network thereby improving the accuracy of topology estimation. Furthermore, we constructed and meticulously annotated a unique dataset comprising image sequences from uniaxial compression tests on rock samples, featuring ground truth labels for semantic segmentation, edge detection, and evolving fracture network topology. Extensive experiments demonstrate FisTopNet's superior performance over established baseline methods. FisTopNet achieved an Intersection over Union (IoU) of 88.14 % and a Topological Similarity of 96.48 %. The IoU score, which quantifies the overlap between predicted and ground truth areas, represents a 12.74 % improvement over the leading competitor, SegFormer. Furthermore, Topological Similarity, an index evaluating the consistency of network connectivity, represents a 1.63 % improvement over the HRNet. In addition, ablation studies further validate the importance of the multi-task design and the temporal processing module. Moreover, our approach proficiently characterized the three-stage evolution of fracture topology and revealed strong correlations between dynamic topological parameters and macroscopic rock mechanical behavior, such as failure mode and peak stress. By leveraging FisTopNet, we propose a robust and automatic methodology for analyzing dynamic fracture processes, thereby facilitating a greater insight into rock failure mechanisms and enhancing engineering design and hazard assessment, with potential applications in geothermal energy extraction, CO₂ geological sequestration, and stability analysis for underground mining and civil engineering projects.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"197 ","pages":"Article 106361"},"PeriodicalIF":7.5,"publicationDate":"2025-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145611883","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental study on triaxial fatigue properties of mudstone interlayers in CAES under synergistic effects of stress amplitude and time interval","authors":"Jinjie Suo ,&nbsp;Jinyang Fan ,&nbsp;Deyi Jiang ,&nbsp;Arezoo Rahimi ,&nbsp;Daniel Nelias ,&nbsp;Zhenyu Yang ,&nbsp;Zongze Li","doi":"10.1016/j.ijrmms.2025.106360","DOIUrl":"10.1016/j.ijrmms.2025.106360","url":null,"abstract":"<div><div>This study investigates the fatigue behavior of mudstone under cyclic triaxial loading conditions, with a focus on the effects of stress amplitude and confining pressure relevant to underground Compressed Air Energy Storage (CAES) operations. Graded triaxial intermittent fatigue tests (GTIF) were conducted to simulate the stress path of intermittent loading. The results show that the fatigue life of mudstone exhibits a non-monotonic dependence on confining pressure: the longest life occurs at 3 MPa, while higher confining pressures (6–12 MPa) cause a pronounced reduction followed by a plateau, indicating a threshold-like confinement effect. The elastic modulus decreases with increasing stress amplitude but, at a given stress ratio, increases with confining pressure, reflecting a trade-off between stress-induced damage and confinement-enhanced stiffness. Residual strain behavior was found to depend on the stress limit interval pattern: upper limit intervals led to reduced residual strain post-rest, whereas lower limit intervals caused strain reversal due to internal stress relaxation. These trends reveal that the loading history significantly influences deformation recovery and potential damage evolution. The damping ratio decreased with increasing confining pressure but increased with stress amplitude, implying that while confining pressure suppresses internal defect activity, higher stress promotes energy dissipation through microcracking. Dissipated energy showed distinct patterns under different loading modes: it increased with stress ratio but decreased with cycle number, highlighting the fatigue softening effect. Interestingly, confining pressure enhanced energy dissipation in upper-limit loading but reduced it under lower-limit conditions. Overall, these results clarify how confining pressure, stress amplitude, and loading intervals jointly govern fatigue life, residual strain, and energy dissipation in mudstone interlayers, and identify measurable damage indicators that can support safer mechanical design and long-term performance assessment of CAES in layered geological formations.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"197 ","pages":"Article 106360"},"PeriodicalIF":7.5,"publicationDate":"2025-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145609208","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of mineralogical features on the mechanical behaviors of granite: A study using physically informed 3D microstructural model","authors":"Changdi He ,&nbsp;Brijes Mishra ,&nbsp;David Oskar Potyondy","doi":"10.1016/j.ijrmms.2025.106355","DOIUrl":"10.1016/j.ijrmms.2025.106355","url":null,"abstract":"<div><div>Mineralogical features, including mineral spatial distribution, shape, and orientation, are important in determining the mechanical behaviors of granite. This effect was investigated by using the X-ray micro-computed tomography (micro-CT) scan on granite specimens (10 mm diameter and 15 mm height) before and after uniaxial compressive strength (UCS) testing. The X-ray micro-CT scan generated thousands of CT images, which were processed using advanced digital image processing (DIP) techniques. Specifically, the Residual Network–Visual Geometry Group16–UNet (Res–VGG16–UNet) model and the circular threshold segmentation technique were applied to identify and map minerals within the CT images. The coordinate information extracted from these mapped minerals was then used to create 3D Subspring Network Breakable Voronoi (SNBV) microstructural models that incorporate the mineral characteristics of tested granite specimens. The models consist of a mesh (3D Voronoi tessellation) of rigid, breakable, Voronoi blocks. The extracted coordinate information, forming a large dataset, was managed by the <span><math><mi>k</mi></math></span>-Dimensional Tree (KD-Tree) algorithm to facilitate mineral type assignment in SNBV models. The models were calibrated by comparing their results with the experimental data obtained from UCS tests. This study further explored the variations in biotite grain spatial distribution, shape, and orientation within a calibrated SNBV model, and examined their impact on the UCS and fracture behaviors of granite, based on a set of simplified microproperties. The results illustrate that as the SNBV model resolution (defined by the number of rigid blocks contained in models with identical physical dimensions) increases, mechanical properties, including UCS and crack initiation and damage strains and stresses, reach constant values. Additionally, the spatial distribution, shape, and orientation of biotite grain affect the UCS of granite, while their effect on the failure strain is minimal. The aspect ratio of biotite grains affects UCS, with <span><math><mi>z</mi></math></span>-axis elongation (aligned with compression) yielding higher UCS than <span><math><mi>x</mi></math></span>-axis elongation (perpendicular to compression).</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"197 ","pages":"Article 106355"},"PeriodicalIF":7.5,"publicationDate":"2025-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145598600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}