International Journal of Rock Mechanics and Mining Sciences最新文献_第5页

Evaluation of Forchheimer equation coefficients for nonlinear flow through rough-walled fractures during shearing 评估剪切过程中通过粗糙壁裂缝的非线性流动的福克海默方程系数

IF 7 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2025-02-01 DOI: 10.1016/j.ijrmms.2024.105992

Xu Zhu , Guangyao Si , Chengguo Zhang , Yingchun Li , Joung Oh

The presence of complex geometric morphology of single rough-walled rock fractures and the occurrence of nonlinear flow complicate the fracture flow process. Even though the nonlinear flow behaviour in single rock fractures has been studied for decades, existing models are still limited in adequately evaluating nonlinear flow behaviour during shearing. In this study, a series of coupled shear-flow tests are conducted on single rock fractures with different surface characteristics under constant normal loads. Regression analyses of the experimental data demonstrate that the Forchheimer equation provides a robust description of nonlinear flow through rough fractures, and its nonlinear coefficients can be determined by quantifying the fracture geometries. The surface and interior geometric characteristics of the fracture are quantitatively represented. The evolutions of these geometric parameters, specifically the peak asperity height and hydraulic aperture, induced by shearing and their effects on nonlinear flow behaviours in rock fractures are also considered and incorporated. An empirical equation is then proposed for the parametric expression of the Forchheimer nonlinear coefficient, which is further used for the prediction of the flow rate during the shear-flow process and the representation of the critical Reynolds number with the fracture geometric characteristics. The proposed equations are validated against experimental results and proven to be effective in predicting and characterising the nonlinear flow behaviour in rock fractures during shearing. The experimental results and the proposed models are expected to advance the understanding and numerical modelling of the nonlinear flow behaviours in fractured rock masses for more practical applications.

单粗壁岩石裂缝复杂几何形态的存在和非线性流动的发生使裂缝流动过程复杂化。尽管对单一岩石裂隙的非线性流动特性进行了数十年的研究，但现有的模型在充分评估剪切过程中的非线性流动特性方面仍然存在局限性。在恒定法向荷载作用下，对具有不同表面特征的单一岩石裂隙进行了一系列剪切-流动耦合试验。对实验数据的回归分析表明，Forchheimer方程能够很好地描述粗糙裂缝的非线性流动，并且可以通过量化裂缝的几何形状来确定其非线性系数。定量地表示了裂缝的表面和内部几何特征。这些几何参数的演变，特别是峰陡高度和水力孔径，剪切诱导及其对岩石裂隙非线性流动行为的影响也被考虑和纳入。在此基础上提出了Forchheimer非线性系数参数表达式的经验方程，并将其用于预测剪切流动过程中的流量和临界雷诺数与断裂几何特征的关系。实验结果验证了所提方程的有效性，证明该方程能够有效地预测和表征岩石断裂剪切过程中的非线性流动特性。实验结果和所提出的模型有望促进对裂隙岩体非线性流动特性的理解和数值模拟，以供更多实际应用。

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引用次数: 0

Water-rock interaction-induced degradation of Jinping marble in in-situ environments: A multi-scale analysis of mechanical behavior

IF 7 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2025-02-01 DOI: 10.1016/j.ijrmms.2024.106011

Chendi Lou , Ru Zhang , Zetian Zhang , Li Ren , Jing Xie , Kun Xiao , Mingchuan Li , Jifang Zhou , Anlin Zhang

In deep engineering practices, surrounding rocks are often subjected to long-term interactions between high pore pressure and high geostress environments, necessitating a thorough understanding of water-rock coupling effect under in-situ conditions. This study investigates these interactions by replicating the deep, high-pressure environment of China Jinping Underground Laboratory (CJPL) through a specially designed high-pressure water-rock coupling apparatus. The research focuses on Jinping marble, conducting in-situ stress saturation treatments under varying solvent pH conditions (7, 8, and 9) and exposure durations (1 d, 23 d, 60 d, and 100 d) at a simulated depth of 2400 m. Extensive macroscopic and microscopic mechanical tests on the treated samples reveal significant time-dependent degradation in key mechanical parameters, including fracture toughness, hardness, and deformation modulus, with the initial decline being more rapid. The fracture surfaces of rock samples treated with pressurized saturation predominantly exhibit transgranular fractures, with intergranular fractures as secondary features. The observed water-rock coupling effects arise from both physical and chemical mechanisms. Notably, within the pH range of 7–9, rock samples treated with a neutral solvent show a more pronounced deterioration trend compared to those treated with an alkaline solvent. Complementary in-situ water analysis from Jinping Mountain further indicates that high confining pressure substantially restricts water infiltration in deep environments. These insights advance the theoretical foundation for safe and effective deep engineering practices.

在深部工程实践中，围岩经常受到高孔隙压力和高地应力环境的长期相互作用，需要深入了解原位条件下的水岩耦合效应。对处理后的试样进行的大量宏观和微观力学试验表明，断裂韧性、硬度和变形模量等关键力学参数的退化具有明显的时间依赖性，且初期下降更为迅速。经加压饱和处理的岩样裂缝表面以穿晶裂缝为主，粒间裂缝次之。所观察到的水岩耦合效应有物理机制和化学机制。值得注意的是，在pH值为7 ~ 9的范围内，中性溶剂处理的岩石样品比碱性溶剂处理的岩石样品表现出更明显的变质趋势。这些见解为安全有效的深层工程实践提供了理论基础。

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引用次数: 0

Meso-mechanical mechanism of ordered mica alignment on the progressive failure process of granite under different lateral stress directions

IF 7 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2025-02-01 DOI: 10.1016/j.ijrmms.2025.106037

Chen Fan , Xia-Ting Feng , Jun Zhao , Cheng-Xiang Yang , Meng-Fei Jiang

Accurately understanding the mechanical properties of surrounding rock is crucial for minimizing the risk of surrounding rock instability. In a deep TBM tunnel, mica minerals in the surrounding rock exhibit an intermittently oriented alignment, which is considered one potential cause of time-delayed failures. Under the same true triaxial stress, creep tests were conducted on granite with different strike angles ω when dip angle β = 50°, to investigate the impact of ordered mica alignment under different lateral stress directions (σ₂ ≠ σ₃). Results show that the strike angle ω also have a significant impact on the progressive failure process of granite under true triaxial stress. In the multi-stage creep tests, the final failure strength of granite at ω = 0° was approximately 73 % higher than that at ω = 90°. Brazilian splitting tests also confirm the crack development at mica tips under different mica orientations, with the maximum difference in tensile strength reaching 37 %. The essence of the impact of mica orientation on rock failure process lies in the promotion of crack initiation and coalescence under high stress. Under a moderate dip angle β, relative sliding between mica cleavage planes is easier when ω = 60° or 90°, leading to crack initiation at mica tips and significantly compromising the load-bearing structure of granite. Based on fracture mechanics, this paper also provides theoretical explanations for the differences in mesoscopic fracturing process of granite with different mica orientations. In surrounding rock stability analyses, it is crucial to consider the complex combinations of rock microstructure and local stress state in the field, which would cause significant variations in surrounding rock stability.

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引用次数: 0

Enhanced discontinuity characterization in hard rock pillars using point cloud completion and DBSCAN clustering 利用点云补全和DBSCAN聚类增强硬岩柱的不连续特征

IF 7 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2025-02-01 DOI: 10.1016/j.ijrmms.2024.106005

Chuanqi Li , Jian Zhou , Kun Du , Ming Tao

This paper proposes a novel strategy to characterize the discontinuities of hard rock pillars in underground mines. In this strategy, the point cloud completion technology is proposed to fill in the missing point clouds caused by defective digital photogrammetry. An improved density-based spatial clustering of applications with noise (DBSCAN) algorithm is developed for accurate discontinuity extraction. A case study is carried out to evaluate and verify the proposed strategy in characterizing discontinuities of hard rock pillars. Furthermore, the performance of the proposed method is compared with other conventional methods in extracting the pillar discontinuities, and the influence of point cloud completion on the characterization performance is discussed. The results indicate that the proposed strategy can accurately extract discontinuities, and that the proposed point cloud completion significantly improves characterization accuracy. Although the proposed strategy has not yet been applied or verified in the discontinuity extraction of other rock masses, it provides a new opinion and a reliable exploration for the discontinuity characterization of hard rock pillars.

本文提出了一种描述地下矿山硬岩柱结构面特征的新方法。在该策略中，提出了点云补全技术来填补由于数字摄影测量缺陷而导致的点云缺失。提出了一种改进的基于密度的带噪声应用空间聚类（DBSCAN）算法，用于精确提取不连续点。通过实例分析，对所提出的方法在硬岩柱结构面表征中的应用进行了评价和验证。此外，将所提方法与其他传统方法在提取柱状结构不连续面方面的性能进行了比较，并讨论了点云补全对表征性能的影响。结果表明，所提出的策略可以准确地提取不连续点，所提出的点云补全方法显著提高了表征精度。虽然该策略尚未在其他岩体的非连续性提取中得到应用或验证，但为硬岩柱的非连续性表征提供了新的观点和可靠的探索。

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引用次数: 0

Elastic wave propagation and attenuation across cemented rock fractures under tension 受拉作用下胶结岩体裂隙弹性波的传播与衰减

IF 7 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2025-02-01 DOI: 10.1016/j.ijrmms.2025.106024

Hui Yang , Qi Zhao , Dongya Han , Qinghua Lei , Huanyu Wu , Xiaolin Huang , Zhiyi Chen , Yu Huang

Tensile loading plays a critical role in geological processes like landslides and earthquakes, as well as engineering applications such as hydraulic fracturing and tunnel excavation. We investigate elastic wave behavior across cemented rock fractures under tensile stress conditions. Ultrasonic measurements and uniaxial direct tension tests were performed concurrently on quartz diorite and diabase specimens with and without individual cemented fractures to determine the influence of tensile stress on the characteristics of elastic waves. Results show that increasing tensile stress leads to enhanced wave attenuation and reduced velocity, amplitudes, and dominant frequency of transmitted waves. These changes are primarily driven by the formation and growth of microcracks near cemented rock fractures under tensile stress. The jointed quartz diorite samples experienced progressive reductions in static and dynamic fracture stiffness. In contrast, jointed diabase samples maintained nearly constant static fracture stiffness and only saw decreases in dynamic fracture stiffness. The reduction in dynamic fracture stiffness is attributed to microscopic damage that modifies elastic wave velocity and dissipation but is not captured by static stress-strain measurements. The gradual decrease in dynamic fracture stiffness reflects stable crack growth, while sudden reductions indicate crack coalescence at the interface. We propose that dynamic fracture stiffness, assessable with seismic wave measurement, is a more reliable indicator of tensile damage than static fracture stiffness due to its sensitivity to low strains and ability to capture microstructural changes. These findings provide valuable insights into seismic methods applied to assess stress conditions on rock discontinuities in the field.

拉伸载荷在滑坡和地震等地质过程以及水力压裂和隧道开挖等工程应用中起着至关重要的作用。我们研究了在拉应力条件下胶结岩石裂缝的弹性波行为。同时对石英闪长岩和辉绿岩试样进行超声测量和单轴直接拉伸试验，以确定拉伸应力对弹性波特性的影响。结果表明，拉应力的增加会导致波的衰减增强，传播波的速度、振幅和主导频率降低。这些变化主要是受拉应力作用下胶结岩石裂隙附近微裂纹的形成和生长驱动的。节理石英闪长岩样品的静态和动态断裂刚度逐渐降低。而节理辉绿岩试样的静态断裂刚度基本保持不变，动态断裂刚度只有下降。动态断裂刚度的降低归因于微观损伤，它改变了弹性波速和耗散，但静态应力-应变测量无法捕捉到。动态断裂刚度的逐渐减小反映了裂纹的稳定扩展，而突然减小则表明裂纹在界面处合并。我们提出，由于动态断裂刚度对低应变的敏感性和捕捉微观结构变化的能力，动态断裂刚度可以用地震波测量来评估，是一个比静态断裂刚度更可靠的拉伸损伤指标。这些发现为应用地震方法评估野外岩石不连续面应力条件提供了有价值的见解。

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引用次数: 0

Meso-damage characterization of chemically corroded rocks under unloading confinement conditions 卸载约束条件下化学腐蚀岩石的细观损伤表征

IF 7 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2025-02-01 DOI: 10.1016/j.ijrmms.2024.106012

Hao Li , Leo Pel , Zhenjiang You , David Smeulders

Characterizing meso-damage and understanding its correlation with macroscopic mechanical responses of rocks under coupled chemical-mechanical (C-M) conditions are crucial for the stability analysis and safety design of underground constructions in chemically corrosive environments. This research proposes a model to quantify coupled C-M meso-damage of rocks, utilizing geochemical surface reaction theory, statistical mechanics, thermodynamic principles, and novel principals proposed in this study, termed Random Energy Release Rate (RERR) and Effective Chemical Damage (ECD). To achieve this goal, a multiscale experimental investigation, including Nuclear Magnetic Resonance (NMR), X-ray diffraction (XRD), Scanning electron microscopy (SEM), pH and ion chromatography analysis, triaxial compression and unloading confinement tests, is employed to examine meso-damage evolution and its linkage with the macro-mechanical responses of limestone under coupled C-M conditions. Based on the experimental investigations, the ECD model is introduced to differentiate chemical damage into effective and apparent categories. Then RERR is proposed to characterize the heterogeneity of damage. Utilizing ECD, along with RERR, the coupled C-M meso-damage model is finally proposed and validated with experimental data. Results show that the evolution of coupled C-M damage follows an S-shaped curve with four stages; Confining pressure limits ECD and C-M damage development, while ECD accelerates C-M damage; As dual-pore geo-media, RERR predominantly originate from the crack-like pores, and ECD is closely tied to crack-like pore closure and rock skeleton flexibility.

在化学-机械（C-M）耦合条件下，表征介观损伤并了解其与岩石宏观机械响应的相关性，对于化学腐蚀环境中地下建筑的稳定性分析和安全设计至关重要。本研究利用地球化学表面反应理论、统计力学、热力学原理以及本研究提出的随机能量释放率（RERR）和有效化学损伤（ECD）新原理，提出了一种量化岩石化学-机械耦合介观损伤的模型。为实现这一目标，本研究采用了多尺度实验研究，包括核磁共振（NMR）、X 射线衍射（XRD）、扫描电子显微镜（SEM）、pH 值和离子色谱分析、三轴压缩和卸载约束试验，以研究石灰石在 C-M 耦合条件下的中观损伤演变及其与宏观力学响应之间的联系。在实验研究的基础上，引入了 ECD 模型，将化学损伤分为有效损伤和表观损伤两类。然后提出了 RERR 模型来描述损伤的异质性。利用 ECD 和 RERR，最终提出了 C-M 中观损伤耦合模型，并用实验数据进行了验证。结果表明，耦合 C-M 损伤的演化遵循四阶段的 S 型曲线；约束压力限制了 ECD 和 C-M 损伤的发展，而 ECD 则加速了 C-M 损伤的发展；作为双孔岩土介质，RERR 主要来源于裂隙状孔隙，而 ECD 与裂隙状孔隙闭合和岩石骨架柔性密切相关。

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引用次数: 0

A micromechanical model for induced anisotropic damage-friction in rock materials under cyclic loading 循环加载下岩石材料诱导各向异性损伤-摩擦细观力学模型

IF 7 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2025-02-01 DOI: 10.1016/j.ijrmms.2024.106014

Jin Zhang , Wenyong Liu , Qiaojuan Yu , Qi-Zhi Zhu , Jian-Fu Shao

This study develops a unified micromechanical induced anisotropic model to predict the instantaneous and longterm behaviors of rock materials under cyclic loading. By integrating a thermodynamic framework with the Mori–Tanaka homogenization method, the model captures the anisotropic damage evolution considering nonuniform microcrack growth. The model incorporates the interaction between microcrack-induced damage and frictional effects, enabling a more accurate prediction of nonlinear behaviors. A fatigue damage variable is introduced to represent the progressive degradation. The plastic deformation is attributed to frictional sliding along oriented microcracks, while instantaneous and fatigue damage evolution are driven by crack growth and subcritical cracking, respectively. The model is validated against experimental data for varying rock types, demonstrating its ability to reproduce key mechanical behaviors, including nonlinear mechanical response, fatigue life, and nonuniform damage evolution. The proposed model provides a robust and comprehensive framework for analyzing the longterm behavior under cyclic loadings.

本研究建立了一个统一的微力学诱导各向异性模型来预测岩石材料在循环荷载作用下的瞬时和长期行为。通过将热力学框架与Mori-Tanaka均质化方法相结合，该模型捕捉了考虑非均匀微裂纹扩展的各向异性损伤演化过程。该模型结合了微裂纹损伤和摩擦效应之间的相互作用，能够更准确地预测非线性行为。引入疲劳损伤变量来表示逐步退化。塑性变形主要由取向微裂纹的摩擦滑动引起，瞬时损伤和疲劳损伤分别由裂纹扩展和亚临界裂纹驱动。该模型通过不同岩石类型的实验数据进行了验证，证明了其重现关键力学行为的能力，包括非线性力学响应、疲劳寿命和非均匀损伤演化。所提出的模型为分析循环荷载下的长期性能提供了一个鲁棒和全面的框架。

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引用次数: 0

Damage zone around underground opening caused by combined blast loading and initial stress unloading 爆破加载与初始应力卸载联合引起的地下开孔周围破坏区

IF 7 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2025-02-01 DOI: 10.1016/j.ijrmms.2024.106018

Rui Zhao , Ming Tao , Murat Karakus

The formation of an Excavation Damaged Zone (EDZ) is a common issue in mining and other geotechnical engineering fields, which impacts the stability of surrounding rock mass. The excavation of deep, stressed rock mass induces stress redistribution and propagates stress waves that form an EDZ around the excavation. Modelling the complex processes of stress relief and adjustment in anisotropic stress states is challenging but essential for understanding EDZ formation mechanisms and optimizing blast design. In this study, we derive the stress response in the surrounding rock mass caused by the initial stress unloading and blast loading in arbitrary stress states. This is achieved by the application of modal superposition and Laplace transform. The impacts of the unloading period, blasting amplitude, and stress state were studied. Then a series of Finite Element Method (FEM) numerical simulations were carried out to obtain the EDZ around the opening under pure unloading and combined loading-unloading. The field observations of the distributions of EDZ in underground mining tunnels excavated by blasting were analysed in conjunction with the theoretical and numerical findings. The results showed the extent of the EDZ increases with initial stress, and at lower stress levels, blasting predominantly governs the formation of the EDZ, while at higher stress levels, unloading and stress redistribution prevail. Blast loading was suggested to be the main cause of the Highly Damaged Zone (HDZ), as the unload-induced redistributed stress and blast loading stress were linearly superimposed in the radial and tangential direction, leading to the elevation in the tangential tensile stress and the radial compressive stress in the rock mass near the excavation boundary.

开挖破坏区（EDZ）的形成是采矿等岩土工程领域普遍存在的问题，影响着围岩的稳定性。深应力岩体的开挖引起应力重分布，并传播应力波，在开挖周围形成电火花区。模拟各向异性应力状态下的应力释放和调整的复杂过程是具有挑战性的，但对于理解EDZ形成机制和优化爆破设计至关重要。在本研究中，我们推导了任意应力状态下初始应力卸载和爆破加载对围岩的应力响应。这是通过应用模态叠加和拉普拉斯变换来实现的。研究了卸荷时间、爆破振幅和应力状态对卸荷效果的影响。在此基础上进行了一系列有限元数值模拟，得到了纯卸载和复合加载-卸载条件下开孔周围的电火花区。结合理论和数值研究结果，分析了地下矿山爆破隧道中电火花区分布的现场观测结果。结果表明：随着初始应力的增加，影响区范围增大；在较低应力水平下，爆破主导影响区形成；在较高应力水平下，卸载和应力重分布主导区形成；爆破荷载是高损伤区形成的主要原因，卸载引起的重分布应力与爆破荷载应力在径向和切向上呈线性叠加，导致开挖边界附近岩体切向拉应力和径向压应力升高。

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引用次数: 0

Leveraging negative pore pressure to constrain post-injection-induced slip of rock fractures 利用负孔隙压力抑制注入后引起的岩石裂缝滑移

IF 7 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2025-02-01 DOI: 10.1016/j.ijrmms.2024.106023

Zhou Fang, Wei Wu

Negative pore pressure caused by unconventional energy production may offer insights into predicting and mitigating post-injection-induced seismicity. Here we presented triaxial shear experiments on sawcut, filled, and natural fractures under positive, zero, and negative pore pressures. The results show that negative pore pressure leads to an increase in the peak strength of the sawcut and filled fractures while reductions in post-peak stressing rate and fracture permeability, inhibiting unstable slip. Our analysis reveals that both the normalized stressing rates per net vented volume in the laboratory and per net production volume in the field decrease during the early stages of fluid extraction and stabilize at zero with long-term extraction. Notably, negative pore pressure develops as the normalized stressing rates approach zero, indicating its role as an indicator for constraining post-injection-induced slip of rock fractures. These findings align well with the observed correlation between net production volume and seismic activity at the Salton Sea Geothermal Field. Our study suggests that monitoring pore pressure can be an alternative method to predict the risk of post-injection-induced earthquakes, particularly in localized regions with isolated fractures experiencing high production volume and limited fluid replenishment.

非常规能源生产引起的负孔隙压力可以为预测和减轻注入后引起的地震活动提供见解。在这里，我们展示了锯切、填充和天然裂缝在正、零和负孔隙压力下的三轴剪切实验。结果表明：负孔隙压力导致锯切充填裂缝的峰值强度增加，峰后应力速率和裂缝渗透率降低，抑制了不稳定滑移；我们的分析表明，在流体萃取的早期阶段，实验室中每净排气体积的归一化应力率和现场的每净产量的归一化应力率都在下降，并在长期萃取中稳定在零。值得注意的是，当归一化应力率接近于零时，负孔隙压力出现，表明其作为约束注入后岩石裂缝滑移的指标。这些发现与观测到的净产量与索尔顿海地热田地震活动之间的相关性很好地吻合。我们的研究表明，监测孔隙压力可以作为预测注后地震风险的一种替代方法，特别是在具有高产量和有限流体补充的孤立裂缝的局部区域。

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引用次数: 0

A novel approach of mitigating fault-slip induced dynamic disasters based on liquid super-lubricity

IF 7 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2025-02-01 DOI: 10.1016/j.ijrmms.2025.106033

Jintong Zhang , Wei Song , Jun Wu , Yue Shen , Zhihong Zhao , Jinjin Li

Fault-slip induced dynamic disasters, such as seismicity and rockburst, pose significant risks to various subsurface engineering projects, and the currently used mitigation methods often involves strategies of modulating in-situ stresses in the surrounding rocks near fault planes timely. Here, we propose an alternative strategy for mitigating fault-slip induced dynamic disasters in terms of reducing friction of faults based on liquid super-lubricity principle. A series of friction experiments were conducted on fault specimens in which deionized water (DW), polyethylene glycol (PEG) solution, graphene oxide (GO coating), PEG with graphene oxide additives (GO in PEG) and ethyl alcohol aqueous solution with graphene oxide additives (GO in EA) were served as lubricants. The experimental results demonstrate that friction coefficients of flat and rough fault specimens were reduced by 3 % and 4 %, 46 % and 28 %, 62 % and 23 %, 74 % and 51 %, 62 % and 48 %, respectively, when lubricated by DW, PEG solution, GO coating, GO in PEG, and GO in EA compared to dry condition. Microscale friction tests and surface characterization were conducted to elucidate the lubrication mechanism of GO additives in PEG. The adsorbed PEG film and graphene layers on contact asperities effectively withstood high pressures, exhibiting low shear stress and preserving a relatively rough surface texture. The results suggest that injecting lubricant solutions into natural faults to modulate friction coefficients can effectively control fault slip and mitigate the risk of dynamic disasters.

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引用次数: 0