International Journal of Rock Mechanics and Mining Sciences最新文献

{"title":"The effect of strain rate on inelastic strain development in porous sandstones deformed under reservoir conditions","authors":"Takahiro Shinohara,&nbsp;Mark Jefferd,&nbsp;Christopher J. Spiers,&nbsp;Suzanne J.T. Hangx","doi":"10.1016/j.ijrmms.2024.105947","DOIUrl":"10.1016/j.ijrmms.2024.105947","url":null,"abstract":"<div><div>Fluid extraction from sandstone oil, gas, or geothermal reservoirs causes elastic and inelastic compaction of the reservoir, which may lead to surface subsidence and induced seismicity, as observed in the Groningen Gas Field, Netherlands. The inelastic compaction is partly caused by rate- or time-dependent processes, meaning that compaction may continue even if production is stopped. To reliably evaluate the impact of prolonged reservoir exploitation and post-abandonment behavior (<span><math><mrow><mo>&gt;</mo><mspace></mspace></mrow></math></span>10–100 years), mechanism-based rate/time-dependent compaction laws are needed. We systematically investigated the effect of strain rate (rates of <span><math><mrow><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>3</mn></mrow></msup></mrow></math></span>–<span><math><mrow><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>9</mn></mrow></msup></mrow></math></span> s<span><math><msup><mrow></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></math></span>) in triaxial compression experiments performed on clay-bearing Bleurswiller sandstone (as an analogue of the Groningen reservoir sandstone) and almost clay-free Bentheimer sandstone, to explore the effect of mineralogy. Our results showed a systematic lowering of stress–strain curves with decreasing axial strain rate in Bleurswiller sandstone at differential stresses exceeding 40%–50% of peak stress (i.e. comparable to typical reservoir stress conditions). By contrast, in Bentheimer sandstone, rate effects were only noticeable at differential stresses <span><math><mo>&gt;</mo></math></span> 70% of peak differential stress. Further investigation of the deformation behavior of Bleurswiller sandstone at varying confining pressure, temperature and pore fluid pH, complemented by microstructural analysis, suggested that the observed rate effects are likely controlled by rate-dependent intergranular frictional sliding at lower differential stress, with an increased role of stress corrosion cracking at higher stress. Extrapolation of our data to reservoir conditions suggests that additional strains of about 10% can be expected, compared to the strain accumulated at laboratory strain rates. Our results show that time-dependent inelastic deformation plays an important role in controlling reservoir deformation, such as of the Groningen gas reservoir. Such effects could lead to an underestimation of surface subsidence and induced seismicity, if not accounted for. The present experiments provide important data for developing physics-based constitutive models for predicting rate/time-dependent reservoir compaction.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"184 ","pages":"Article 105947"},"PeriodicalIF":7.0,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integration of automatic discontinuity identification and multi-scale hierarchical modeling for stability analysis of highly-jointed rock slopes","authors":"Ya-ping Wang ,&nbsp;Jia-wen Zhou ,&nbsp;Jun-lin Chen ,&nbsp;Yu-chuan Yang ,&nbsp;Fei Ye ,&nbsp;Hai-bo Li","doi":"10.1016/j.ijrmms.2024.105955","DOIUrl":"10.1016/j.ijrmms.2024.105955","url":null,"abstract":"<div><div>The geometric shape of the slope and the distribution characteristics of the complex fracture system significantly impact the stability of highly-jointed rock slopes. Constructing an accurate three-dimensional (3D) geological model is crucial for the 3D stability analysis of these slopes. However, the numerous minor discontinuities in rock slopes complicate model construction and reduce computational efficiency. This paper proposes a stability-analysis method for highly-jointed rock slopes that integrates automatic identification of real discontinuities with hierarchical modeling of 3D multi-scale fracture networks. Real discontinuity information was automatically extracted using a developed fuzzy k-means clustering algorithm, which calculated the number of dominant discontinuity sets and their spatial distribution laws. The Monte Carlo stochastic method was then employed to generate a complex 3D fracture-network system with statistical characteristics identical to those of the real discontinuities. The multi-scale fracture network was classified based on trace length. Given the numerous minor discontinuities that significantly impact computational efficiency, synthetic rock mass technology was utilized to determine the representative elementary volume with equivalent rock-mass characteristics to reasonably generalise the geological engineering model of rock slopes with complex fractures. In applying the slope-excavation stability analysis and evaluation to the Feishuiyan rock slope, the method achieved high automation in contactless scanning, efficient identification of discontinuity effects, accurate model calculations, and reliable stability analysis during the generalization of the geological engineering model. This method proved effective for stability analysis of highly-jointed rock-slope excavations, and is significant for engineering evaluation, as well as for disaster prevention and mitigation of complex rock slopes.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"184 ","pages":"Article 105955"},"PeriodicalIF":7.0,"publicationDate":"2024-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142660332","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":"Development of a dynamic cumulative damage model and its application to underground hydropower caverns under multiple blasting","authors":"Yimo Zhu,&nbsp;Yaolan Tang,&nbsp;Huachuan Wang,&nbsp;Qian-Bing Zhang","doi":"10.1016/j.ijrmms.2024.105948","DOIUrl":"10.1016/j.ijrmms.2024.105948","url":null,"abstract":"<div><div>Underground infrastructures are crucial for resource extraction, energy storage, and space utilisation. The geomaterials that make up these structures, such as rock and concrete, are subjected to multiaxial stress conditions and are frequently exposed to dynamic and extreme loadings caused by both natural disasters and human activities. These stresses are particularly significant during the construction phase, which involves operations such as drilling and blasting excavation, as well as during the operational phase, which may include events like explosions. For instance, while drilling and blasting induce rock breakage within the excavated profile as designed, they inevitably lead to the formation of a damage zone in the surrounding rock mass. Moreover, the cumulative effects of sequential excavations and multiple blasts can cause significantly greater damage, thereby threatening the stability of tunnel structures during the operation phase. This paper highlights the importance of thoroughly analysing these phenomena during both static and dynamic loadings to ensure the stability of underground infrastructures. To address these challenges, a rate-dependent damage constitutive model is proposed for geomaterials to assess the impacts of blasting loads and the cumulative damage resulting from repeated blasts. The model is conceptualised using the strength envelope of loading-unloading curves to represent the progressive accumulation of damage under repeated impacts. Through theoretical derivation, a dynamic cumulative damage model is developed, based on a modified Mohr-Coulomb strain-softening model incorporating rate-dependent parameters, and is validated against dynamic experimental data. The model captures the transition between static strain-softening and dynamic cumulative damage, triggered by a critical strain-rate threshold. The applicability of the model is demonstrated through simulations of tunnel excavation, emphasising the impact of blasting loads and the accumulation of damage zones. To assess its practical feasibility, the developed model is applied to simulate different excavation scenarios for an underground hydropower cavern. Damage in the surrounding rock mainly results from static unloading and/or dynamic disturbances. Blasting construction, in particular, causes significant damage in tunnel intersection zones and the connecting areas of two benches, leading to increased displacement and higher damage levels compared to static excavation. To mitigate excessive damage while maintaining the construction timeframe, it is recommended to consider alternating cycles of dynamic loading and static excavation unloading continuously, which helps understand damage formation in critical zones without significantly delaying project completion.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"184 ","pages":"Article 105948"},"PeriodicalIF":7.0,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142578527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Asymmetric failure mechanisms of anisotropic shale under direct shear","authors":"Chunfeng Ye ,&nbsp;Heping Xie ,&nbsp;Fei Wu ,&nbsp;Jianjun Hu ,&nbsp;Li Ren ,&nbsp;Cunbao Li","doi":"10.1016/j.ijrmms.2024.105941","DOIUrl":"10.1016/j.ijrmms.2024.105941","url":null,"abstract":"<div><div>This study performed mechanical tests and monitored acoustic emissions (AE) in shale samples with six bedding layer orientations (<em>β</em> = 0°, 30°, 60°, 90°, 120°, and 150°) to investigate the progressive damage mechanisms under direct shear. The results revealed that the peak shear load (<em>P</em>_<em>cr</em>), crack initiation threshold (<em>P</em>_<em>ci</em>), crack damage threshold (<em>P</em>_<em>cd</em>), and cumulative AE count exhibited an approximate M-shaped trend as the bedding angle increased. The <em>P</em>_<em>ci</em>, <em>P</em>_<em>cd</em>, and <em>P</em>_<em>cr</em> values were minimal for shale specimens with <em>β</em> = 0°, <em>P</em>_<em>cd</em> and <em>P</em>_<em>cr</em> were maximal at <em>β</em> = 150° (followed by <em>β</em> = 60°), and <em>P</em>_<em>ci</em> reached the maximum at <em>β</em> = 60°. Thus, shale exhibits complex and asymmetric mechanical behavior under direct shear, a phenomenon seldom documented. The three-dimensional spatiotemporal evolution of the AE, evolution of <em>b</em>-values, peak frequency distribution, and the rise angle-average frequency (RA-AF) indicated that the microscale mechanism governing the asymmetric progressive failure of anisotropic shale under direct shear involved significant asymmetry in the formation type and scales of cracks. The AE characteristics of anisotropic shale were analyzed using multifractal theory. The width of the multifractal spectrum, Δ<em>θ</em>, accurately reflected the anisotropic characteristics of the AE time series. Moreover, the variation in the fractal dimension, Δ<em>f</em>, indicated that the different probabilities of microcracks with high AE energy are the fundamental cause of the shale's asymmetric failure.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"183 ","pages":"Article 105941"},"PeriodicalIF":7.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142552424","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":"Rock fragmentation of simulated transversely isotropic rocks under static expansive loadings","authors":"Chundong Shi ,&nbsp;Wen Nie ,&nbsp;Guowei Ma ,&nbsp;Jiangyong Sun ,&nbsp;Junlin Wang ,&nbsp;Li Wang","doi":"10.1016/j.ijrmms.2024.105944","DOIUrl":"10.1016/j.ijrmms.2024.105944","url":null,"abstract":"<div><div>Rock fragmentation is a critical process for mineral extraction and for mitigating overstressed rock in geotechnical applications. In this study, 3D-printed concrete was used to simulate the stratified rock mass, and experimental and numerical methods were employed to investigate crack propagation under static expansive loadings in transversely isotropic rocks. Two types of cracks were observed in the experiments: P-type (a crack propagates primarily along the weak layer) and T-type (a crack propagates across the weak layers) cracks. The findings revealed that the orientation of layers significantly influenced the initiation and propagation of cracks, with P-type cracks commonly observed in simpler P-P mode fragmentations and more complex P-P-T modes emerging under higher expansive loadings. P-T-T modes were characterized by the simultaneous presence of the T-type crack after an initial P-type crack. The AE energy levels in the P-P-T and P-T-T modes were much higher than those in the P-P mode. 2D-DDA models were further built to understand the effects of the loading scales, layer angles, and locations of weak layers on the cracking sequences. The results provided detailed insights into stress evolutions and the impact of expansive loadings on crack initiation and propagation.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"183 ","pages":"Article 105944"},"PeriodicalIF":7.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142561347","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":"Multi-stage evolution of pore structure of microwave-treated sandstone: Insights from nuclear magnetic resonance","authors":"Yao Zhang ,&nbsp;Yanan Gao ,&nbsp;Liyuan Yu","doi":"10.1016/j.ijrmms.2024.105952","DOIUrl":"10.1016/j.ijrmms.2024.105952","url":null,"abstract":"<div><div>Microwave fracturing has great potential in improving the efficiency of hard rock breaking. However, the pore evolution, which can be regarded as the damage accumulation and progressive failure of the rock subjected to microwave irradiation, remains unclear. In this study, nuclear magnetic resonance (NMR) is employed to investigate the pore evolution and fracture mechanism of the sandstone under different microwave power levels. The results show that the pore evolution of the specimens, including distribution of pore size, the weight in volume of various-sized pore, and porosity, exhibits different changing trends under various microwave power levels. The pore evolution of the specimens under microwave irradiation can be categorized into four phases: overall pore expansion, localized pore closure in the internal region, micro-cracks propagation induced by thermal stress, and macro-cracking (or melting). Moreover, pore evolution also plays a crucial role in the decomposition and evaporation of bound water, particularly when the specimens experience fractures triggered by thermal stress induced by the microwave treatment (TSIMT). The employing of NMR imaging (NMRI) description also provides an auxiliary and effective illustration on the pore evolution of the specimens under microwave irradiation. Finally, the mechanism of microwave-assisted rock breaking under different power levels is comprehensively discussed based on the NMR results from a microscopic perspective. It is anticipated that the findings of this study can provide valuable insights for enhancing the efficiency of microwave-assisted rock breaking.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"183 ","pages":"Article 105952"},"PeriodicalIF":7.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142573463","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":"Monitoring stress-induced brittle rock mass damage for preventative support maintenance","authors":"Robert McMillan ,&nbsp;Erik Eberhardt ,&nbsp;Ryan Campbell ,&nbsp;Avesiena Primadiansyah","doi":"10.1016/j.ijrmms.2024.105927","DOIUrl":"10.1016/j.ijrmms.2024.105927","url":null,"abstract":"<div><div>Stress-induced brittle fracturing near an excavation boundary results in a volume increase, known as bulking. Excessive bulking places added demand on the rock support, which, if not detected and addressed through preventative support maintenance (i.e., proactively added reinforcement), can cause the support to fail, leading to a safety hazard and costly production delays for underground mining operations. For caving mines, these project risks are exacerbated during cave establishment due to the large abutment stress from undercutting that redistributes and concentrates stresses near excavations critical for production. This paper reports the findings from research conducted to develop and improve geotechnical monitoring practices to support preventative support maintenance in deep mining operations. This research uses a unique geotechnical monitoring database collected for the Deep Mill Level Zone panel cave mine. The data was collected across a large footprint during the mine's ramp-up period and represents an initial step toward best practices for data collection at cave mines operating in high-stress environments. Borehole camera surveys supplemented by multi-point borehole extensometers have been used to determine the depth of stress fracturing in pillar walls as a function of the distance away from the undercut. Convergence measurements and LiDAR scanning are used to characterize the corresponding rock mass bulking. The results show that the interpretation of monitoring data can be used to identify the long-term depth of stress fracturing and bulking trends in response to undercut advances. These show that direct measures of stress-induced fracturing damage provide an early indication of excavations vulnerable to bulking and that LiDAR scanning is an effective method for capturing the onset of bulking and anticipating local areas likely to experience greater deformation demand as bulking progresses. Proactive and strategic geotechnical monitoring based on the long-term depth of stress-induced fracturing trends is proposed to assist with preventative support maintenance practices.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"183 ","pages":"Article 105927"},"PeriodicalIF":7.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142552488","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":"Modeling of thermally driven longitudinal fractures along a vertical well","authors":"Bin Chen ,&nbsp;Quanlin Zhou","doi":"10.1016/j.ijrmms.2024.105942","DOIUrl":"10.1016/j.ijrmms.2024.105942","url":null,"abstract":"<div><div>Fluid injection via a vertical well into a high-temperature formation may induce <em>multiple longitudinal</em> thermal fractures, which may eventually transition to <em>two-wing</em> fractures during fracture propagation, depending on horizontal stress ratio <span><math><mrow><mi>κ</mi></mrow></math></span>. In this study, we develop a plane strain model with radial heat conduction to investigate either two-wing fractures under highly anisotropic stresses <span><math><mrow><msub><mi>κ</mi><mrow><mi>h</mi><mi>a</mi></mrow></msub><mo>≫</mo><mn>1</mn></mrow></math></span> or multiple fractures under isotropic stresses <span><math><mrow><mi>κ</mi><mo>=</mo><mn>1</mn></mrow></math></span>. The coupled dimensionless elasticity equation and criteria of fracture propagation (and <em>arrest</em>) are formulated, discretized, and solved iteratively (with two special algorithms). Two additional critical model parameters are dimensionless effective confining stress <span><math><mrow><mi>T</mi></mrow></math></span> and wellbore radius <span><math><mrow><mi>A</mi></mrow></math></span>. The multiple-fracture solution of dimensionless fracture length <span><math><mrow><mi>L</mi></mrow></math></span>, angular spacing <span><math><mrow><mi>D</mi></mrow></math></span>, and aperture consists of solutions for competitive propagation of fractures with arrests in the near-wellbore region and the subsequent stable propagation of fractures away from the wellbore. Both the multiple-fracture and two-wing-fracture solutions accurately capture the early-time transient and late-time power-law changes with dimensionless time <span><math><mrow><mi>τ</mi></mrow></math></span>, as verified numerically. The late-time fracture propagation follows scaling law <span><math><mi>L</mi><mo>=</mo><mi>f</mi><mfenced><mrow><mi>T</mi><mo>,</mo><mi>A</mi><mo>,</mo><mi>D</mi></mrow></mfenced><msup><mi>τ</mi><mrow><mfenced><mrow><mn>1</mn><mo>−</mo><mn>2</mn><mi>T</mi></mrow></mfenced><mo>/</mo><mn>2</mn></mrow></msup></math></span>. These solutions and scaling laws can be used to well bound a <em>general</em> solution with <span><math><mrow><mn>1</mn><mo>&lt;</mo><mi>κ</mi><mo>&lt;</mo><msub><mi>κ</mi><mrow><mi>h</mi><mi>a</mi></mrow></msub></mrow></math></span> as demonstrated numerically for a geothermal site, for which the maximum fracture length reaches 0.45, 2.71, and 16.42 m in 1, 100 and 10,000 days of cooling, respectively. The applicability of the assumptions used in the theoretical and numerical analysis is discussed.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"183 ","pages":"Article 105942"},"PeriodicalIF":7.0,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538896","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":"An elastoplastic solution for lined hydrogen storage caverns during excavation and operation phases considering strain softening and dilatancy","authors":"Kai Qiu ,&nbsp;Shuchen Li ,&nbsp;Zhongzhong Liu ,&nbsp;Meng Yuan ,&nbsp;Shisen Zhao ,&nbsp;Zeen Wan","doi":"10.1016/j.ijrmms.2024.105949","DOIUrl":"10.1016/j.ijrmms.2024.105949","url":null,"abstract":"<div><div>Underground hydrogen energy storage (UHES) in lined rock caverns (LRCs) represents a crucial solution to the challenge of unstable and uneven clean energy generation. Nevertheless, the attainment of enhanced storage efficiencies frequently necessitates the utilization of elevated hydrogen storage pressures. Consequently, a comprehensive understanding of the elastic-plastic mechanical response of surrounding rock under hydrogen pressure is of paramount importance for ensuring the safety of UHES. In this study, an elastoplastic solution of LRCs during construction and operation phases is established. Two essential phenomena affecting the post-peak mechanical responses of surrounding rock, strain softening and dilatancy, are coupled into the plastic solution. A computational process is developed and its accuracy is validated through comparison with numerical models. The influence of surrounding rock quality parameters, strain softening and dilatancy parameters, concrete quality parameters and hydrogen pressure on the radius of the plastic softening zone (<em>R</em>_<em>s</em>) and plastic residual zone (<em>R</em>_<em>r</em>) were analyzed. Results show that higher surrounding rock quality can effectively reduce both <em>R</em>_<em>s</em> and <em>R</em>_<em>r</em>. Nevertheless, when the surrounding rock quality already reaches a high standard, such as <em>c</em>₁ &gt; 3.5 MPa, <em>φ</em>₁ &gt; 65°, or <em>E</em> &gt; 55 MPa, it becomes inefficient to overly pursue further improvements in the surrounding rock quality. Furthermore, the strain softening and dilatancy phenomena only affect <em>R</em>_<em>r</em>. Additionally, the concrete lining with higher stiffness can share a larger portion of the hydrogen pressure, thus reducing both <em>R</em>_<em>s</em> and <em>R</em>_<em>r</em>. Notably, When the elastic modulus of concrete increases from 20 MPa to 40 MPa, <em>R</em>_<em>r</em> decreases by 31.98 % and <em>R</em>_<em>s</em> decreases by 20.96 %. Moreover, the critical hydrogen pressure (<em>P</em>_<em>Hcr</em>) at which the surrounding rock begins to enter a plastic state is proportional to the ground stress (<em>P</em>₀). Specifically, when <em>P</em>₀ is increased sequentially from 2.5 MPa to 3.0 MPa and 3.5 MPa, <em>P</em>_<em>Hcr</em> sequentially becomes 2.4 MPa, 4.0 MPa, and 5.0 MPa. The findings presented in this study contribute to improving the safety of LRCs during construction and operation.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"183 ","pages":"Article 105949"},"PeriodicalIF":7.0,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142538808","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 fault activation-shearing-sliding peridynamic model exploring the role of static and kinetic frictional contacts","authors":"Zhen Yang ,&nbsp;HanYi Wang ,&nbsp;Mukul Sharma ,&nbsp;Erdogan Madenci","doi":"10.1016/j.ijrmms.2024.105946","DOIUrl":"10.1016/j.ijrmms.2024.105946","url":null,"abstract":"<div><div>Understanding fault dynamics is essential for comprehending the underlying mechanisms of seismic events. This study introduces a novel fault activation-shearing-sliding model within a peridynamic (PD) framework, characterized by distinctly defined static and kinetic frictional behaviors. Static friction bonds are developed to sustain normal forces perpendicular to the fault plane and to manage tangential frictional forces along the fault's geometry. The failure of these bonds is directly linked to fault activation, while the ensuing sliding phase is governed by a short-range kinetic friction model. Additionally, an adaptive identification method is proposed to accurately determine local unit normal vectors on arbitrarily shaped contact surfaces. The effectiveness and applicability of the model are validated through fault activation and plate sliding friction tests. The model is further utilized to investigate the effects of local geometry, roughness, and friction coefficients on fault behavior, with comparisons to experimental results. Observations indicate that the dominant factors influencing fault shear resistance vary across stages, primarily involving static friction during activation, compaction deformation during shearing, and kinetic friction during sliding. When shear resistance is primarily governed by friction, it exhibits heightened sensitivity to various shear forces, including those from indirect loading disturbances.</div></div>","PeriodicalId":54941,"journal":{"name":"International Journal of Rock Mechanics and Mining Sciences","volume":"183 ","pages":"Article 105946"},"PeriodicalIF":7.0,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142535664","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}