Rock Mechanics Bulletin最新文献

Hybrid XGBoost - 3D FEA approach for predicitng bearing capacity of rectangular foundations on rock slopes 岩质边坡矩形地基承载力预测的混合XGBoost - 3D有限元方法

IF 7

Rock Mechanics Bulletin

Pub Date : 2026-07-01 Epub Date: 2025-11-14 DOI: 10.1016/j.rockmb.2025.100274

Huu Nghia Bui , Suraparb Keawsawasvong , Hoang Nghi Le , Duy Tan Tran , Trong Nghia Le , Van Qui Lai

This study investigates the bearing capacity of a sloping rock foundation beneath rectangular and, in particular, square footings. Additionally, the study proposes a novel hybrid machine learning approach, namely MPA-XGBoost, and develops a Graphical User Interface (GUI) that enables end-users to predict the bearing capacity of foundations without requiring any complex computations. Numerical simulations are conducted via PLAXIS 3D software, which incorporates the finite element method and the Hoek-Brown failure criterion. Through a series of design charts, the correlation between the bearing capacity factor and six input parameters is explored: slope angle (β), intact rock yield (m_i), geological strength index (GSI), compressive strength ratio (γB/σ_ci), dimension ratio (L/B), and setback ratio (b/B). Regarding the machine learning part, the study employs the XGBoost model integrated with the Marine Predators Algorithm (MPA) as an optimization technique. The obtained results demonstrate that the design charts clearly illustrate the influence of various parameters on the bearing capacity. Furthermore, in the failure mechanism analysis when investigating the effect of the geological strength index (GSI) parameter, the incremental displacements show both decreasing and increasing trends, which can be attributed to the indirect influence of the parameters E and ν. Finally, the machine learning results indicate that the application of the Marine Predators Algorithm (MPA) improved the model's accuracy to 99.93%, compared to 99.87% achieved by the default XGBoost model. In addition, a Graphical User Interface (GUI) was proposed to facilitate practical applications.

本研究调查了矩形，特别是方形地基下倾斜岩石地基的承载能力。此外，该研究提出了一种新的混合机器学习方法，即MPA-XGBoost，并开发了一个图形用户界面（GUI），使最终用户能够在不需要任何复杂计算的情况下预测基础的承载力。采用PLAXIS三维软件，结合有限元法和Hoek-Brown破坏准则进行了数值模拟。通过一系列的设计图表，探讨了承载力系数与边坡角（β）、完整岩石屈服量（mi）、地质强度指数（GSI）、抗压强度比（γB/σci）、尺寸比（L/B）、退退比（B/ B） 6个输入参数的相关性。在机器学习部分，本研究采用了结合海洋掠食者算法（MPA）的XGBoost模型作为优化技术。计算结果表明，设计图表清楚地反映了各参数对承载力的影响。此外，在研究地质强度指标（GSI）参数影响的破坏机制分析中，增量位移呈现减小和增大的趋势，这可归因于参数E和ν的间接影响。最后，机器学习结果表明，海洋掠食者算法（MPA）的应用将模型的准确率提高到99.93%，而默认XGBoost模型的准确率为99.87%。此外，为了便于实际应用，还提出了图形用户界面（GUI）。

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引用次数: 0

Experimental investigation on fatigue mechanical behavior and energy evolution characteristic of fine-grained marble under multilevel constant-amplitude cyclic loading 多级等幅循环加载下细粒大理岩疲劳力学行为及能量演化特征试验研究

IF 7

Rock Mechanics Bulletin

Pub Date : 2026-07-01 Epub Date: 2025-10-31 DOI: 10.1016/j.rockmb.2025.100269

Min-Zhen Zhang , Yu Song , Chang-Hong Li , Yan-Lin Zhao , Jin-Zhou Tang , Ke-Sheng Li

This study systematically investigates the mechanical behavior and energy evolution mechanisms of marble under multilevel constant-amplitude cyclic loading through triaxial tests conducted at various confining pressures (0–30 MPa). Using the MTS815 electro-hydraulic servo-controlled rock mechanics testing system, pure white calcite marble specimens were subjected to cyclic loading. The results demonstrate that the stress-strain curves of marble exhibit five distinct stages, with increasing confining pressure significantly prolonging fatigue life and enhancing plastic deformation characteristics. The evolution of peak strain and secant modulus reveals a transition from brittle to ductile behavior under higher confining pressures. Energy analysis indicates that both total input energy and elastic strain energy increase stepwise with rising stress levels, while cumulative energy density follows a parabolic relationship with the stress ratio (φ), and dissipated energy grows approximately linearly. The energy distribution ratios (elastic strain energy ratio η_e, dissipated energy ratio η_d, and energy consumption coefficient η) highlight the critical influence of confining pressure on energy conversion mechanisms, particularly showing a notable shift in energy partitioning behavior near 25 MPa. These findings provide a theoretical foundation for assessing the long-term stability of rocks in deep underground engineering applications.

通过不同围压（0 ~ 30 MPa）下的三轴试验，系统研究了大理岩在多级恒幅循环加载下的力学行为和能量演化机制。采用MTS815电液伺服岩石力学试验系统，对纯白色方解石大理岩试样进行了循环加载试验。结果表明：大理岩的应力-应变曲线表现为5个阶段，围压的增加显著延长了大理岩的疲劳寿命，增强了大理岩的塑性变形特性；在高围压作用下，峰值应变和割线模量的演化过程显示出脆性向延性的转变。能量分析表明，随着应力水平的升高，总输入能量和弹性应变能逐渐增加，累积能量密度与应力比φ呈抛物线关系，耗散能量呈近似线性增长。能量分布比（弹性应变能比ηe、耗散能比ηd和能量消耗系数η）突出了围压对能量转换机制的关键影响，特别是在25 MPa附近，能量分配行为发生了显著变化。研究结果为深部地下工程中岩石长期稳定性评价提供了理论基础。

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引用次数: 0

Investigation of nanoindentation for evaluating the cyclic loading-unloading mechanical properties of heterogeneous coal 评价非均质煤循环加卸载力学性能的纳米压痕研究

IF 7

Rock Mechanics Bulletin

Pub Date : 2026-07-01 Epub Date: 2025-09-07 DOI: 10.1016/j.rockmb.2025.100253

YuKai Fu , Yongzheng Wu , Sifeng He , Penghe Zhou , Junchen Li , Jie He

Exploring the meso-mechanical response of heterogeneous coal is crucial for understanding its macro mechanical behavior in coal mining, CO₂ storage, and coal bed methane production. However, a key gap remains in the insufficient elucidation of the precise linkage between heterogeneity-driven meso-response and macro-performance. In this investigation, nanoindentation tests were performed to compare the force-depth curves, reduced Young's modulus (E_r), hardness (H_IT), and the effect of holding time. Cyclic loading-unloading experiments were conducted at eight points of a polished coal sample, resulting in history cycles at five force levels (50, 100, 150, 200, and 250 mN). The mesoscopic mechanical properties were calculated at each cycle, and the time-dependent deformations at holding times of 5 s and 150 s were compared. Notably, the force-depth curves exhibited a "pop-in" phenomenon. The results indicate that the maximum depth increases with higher loads and cycles. Furthermore, the 150 s holding time resulted in larger deformations compared to the 5 s holding time. Both E_r and H_IT decrease with increasing cycles and load, and there exists a positive correlation between H_IT and E_r. The mean macro Young's modulus (E = 2.22 GPa) is smaller than the mean meso reduced Young's modulus (E_r = 12.28 GPa). The hardness ranges from 0.33 GPa to 0.89 GPa, with a mean value of 0.57 GPa. Due to the heterogeneity at both meso and macro scales, the test results vary across different positions.

探索非均质煤的细观力学响应对于理解其在煤炭开采、二氧化碳储存和煤层气生产中的宏观力学行为至关重要。然而，在异质性驱动的中观反应和宏观表现之间的精确联系的阐明方面仍然存在一个关键的差距。在本研究中，进行了纳米压痕测试，比较了力-深度曲线、降低杨氏模量（Er）、硬度（HIT）和保温时间的影响。在抛光煤样品的8个点上进行了循环加载-卸载实验，得到了5个力水平（50、100、150、200和250 mN）的历史循环。计算了每次循环时的细观力学性能，并比较了保温5 s和保温150 s时的随时间变形。值得注意的是，力-深度曲线呈现出“弹出”现象。结果表明，最大深度随载荷和循环次数的增加而增加。此外，150 s的保温时间比5 s的保温时间导致更大的变形。Er和HIT随循环次数和负荷的增加而减小，HIT与Er之间存在正相关关系。平均宏观杨氏模量（E = 2.22 GPa）小于平均介观缩减杨氏模量（Er = 12.28 GPa）。硬度范围为0.33 ~ 0.89 GPa，平均值为0.57 GPa。由于中观和宏观尺度的异质性，不同位置的测试结果会有所不同。

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引用次数: 0

Reconstruction of laminated shale specimens through advanced physics-informed image processing 通过先进的物理信息图像处理重建层状页岩标本

IF 7

Rock Mechanics Bulletin

Pub Date : 2026-07-01 Epub Date: 2026-01-13 DOI: 10.1016/j.rockmb.2025.100299

Gaobo Zhao , Mindi Ruan

Shale is distinguished from other rocks by its laminated and fissile nature, as it consists of many thin layers and easily splits into thin pieces along the bedding planes. A common approach in a geomechanical simulation of shale is to simplify its complex structure by representing bedding planes as continuous, straight, and equidistant. This approach is acceptable for approximating the general behavior of shale and it is numerically efficient, but also limits our understanding of the true mechanical response of shale to mining-induced stress changes. This paper discussed the limitations of these assumptions and reconstructed laminated shale specimens through image processing to capture bedding planes and through numerical simulation to calibrate their micro-properties. Specifically, this paper used an advanced physics-informed image processing method to extract the coordinates, number, spacing, length, and frequency of the bedding planes, forming a comprehensive geometry database. Using this database, a laminated shale specimen modeling (S1) was developed using UDEC software. A systematic modeling calibration procedure is proposed and applied to calibrate the model by obtaining a final set of calibrated micro-properties, which are verified through comparative analyses of shale specimens with and without flaws, as well as specimens with extracted and parallel bedding planes, along with a reasonableness analysis of predicted bedding planes using a bedding plane geometry database. Furthermore, two more shale specimens (S2, S3) were reconstructed, which incorporate extracted bedding planes and calibrated micro-properties. The results show that the three reconstructed shale specimens achieve stress-strain behaviors and crack propagation that match those observed in the laboratory. This paper bridges the gap between the shale complex structure and geomechanical simulations by introducing an advanced physics-informed image processing approach for an accurate representation of bedding planes and micro-properties.

页岩与其他岩石的不同之处在于它的层状和可裂变性质，因为它由许多薄层组成，并且很容易沿着层理平面分裂成薄块。页岩地质力学模拟的一种常用方法是通过将层理面表示为连续、直和等距来简化其复杂的结构。这种方法对于近似页岩的一般行为是可以接受的，它在数值上是有效的，但也限制了我们对页岩对开采引起的应力变化的真实力学响应的理解。本文讨论了这些假设的局限性，并通过图像处理捕获层理平面，通过数值模拟校准其微观性质，重建了层状页岩样品。具体而言，本文采用先进的物理信息图像处理方法提取了层理平面的坐标、数量、间距、长度和频率，形成了一个完整的几何数据库。利用该数据库，利用UDEC软件开发了层状页岩样品模型（S1）。提出了一种系统的建模校准程序，并应用该程序对模型进行校准，通过对有缺陷和无缺陷的页岩样品、提取的层理面与平行的层理面进行对比分析，并利用层理面几何数据库对预测的层理面进行合理性分析，得到一组最终校准的微观性质。在此基础上，利用提取的层理平面和校正后的微观性质，重构了2个页岩样品（S2、S3）。结果表明，3个重建页岩试样的应力-应变行为和裂纹扩展与实验室观测结果吻合。本文通过引入先进的物理信息图像处理方法来精确表示层理平面和微观性质，弥合了页岩复杂结构和地质力学模拟之间的差距。

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引用次数: 0

Simultaneous propagation of multiple hydraulic fractures in crystalline rock: A numerical investigation based on coupled fluid-solid discrete element framework 基于流固耦合离散元框架的结晶岩水力裂缝同步扩展数值研究

IF 7

Rock Mechanics Bulletin

Pub Date : 2026-07-01 Epub Date: 2025-11-20 DOI: 10.1016/j.rockmb.2025.100277

Suifeng Wang , Tao Wang , Sheng Li , Defu Tong , Taiyi Chen

The simultaneous multiple hydraulic fracturing treatment has been extensively employed in Enhanced geothermal systems (EGS) to increase the complexity and area of artificial fractures. However, the interaction between hydraulic fractures (stress shadowing effect) often occurs, leading to unpredictable fracture paths and unsatisfactory production outcomes. In order to investigate the mechanism behind the stress shadowing during simultaneous multiple hydraulic fracturing in crystalline rock, this study proposes a Hydro-Grain-Texture Model based on discrete element method that can consider the effects of mineral heterogeneity and pre-existing microcrack anisotropy. The results demonstrate that the simultaneous multiple hydraulic fracturing results in crystalline rock are influenced collectively by the confining stress, injection point spacing, mineral heterogeneity, and microcracks anisotropy. Due to the lower strength of grain boundaries, hydraulic fractures are more prone to deflect along these boundaries under the influence of the stress shadowing effect during their propagation. Conversely, when the orientation of pre-existing microcracks is approximately parallel to the direction of hydraulic fracture propagation, their capturing effect can facilitate the ability of hydraulic fractures to overcome the stress shadow effect.

为了增加人工裂缝的复杂性和面积，在增强型地热系统（EGS）中广泛采用了同时多次水力压裂处理。然而，水力裂缝之间的相互作用（应力阴影效应）经常发生，导致不可预测的裂缝路径和不理想的生产结果。为了研究结晶岩同时多次水力压裂过程中应力阴影产生的机理，本研究提出了一种基于离散元法的考虑矿物非均质性和预先存在微裂缝各向异性影响的水粒织构模型。结果表明，结晶岩中同时多次水力压裂结果受围应力、注入点间距、矿物非均质性和微裂缝各向异性的共同影响。由于晶界强度较低，水力裂缝在扩展过程中受应力阴影效应的影响，更容易沿晶界发生偏转。反之，当已存在微裂缝的取向与水力裂缝扩展方向近似平行时，微裂缝的捕获效应有利于水力裂缝克服应力阴影效应。

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引用次数: 0

Insights of microstructures and lithofacies on fracture process zone of organic-rich shale 富有机质页岩破裂过程带的微结构与岩相特征

IF 7

Rock Mechanics Bulletin

Pub Date : 2026-07-01 Epub Date: 2026-01-08 DOI: 10.1016/j.rockmb.2025.100300

Shenjian Li , Mao Sheng , Chao Deng , Shizhong Cheng , Zhiwei Wang , Yiwen Xu , Peng Xu , Shouceng Tian , Gensheng Li

The fracture process zone (FPZ) plays a critical role in determining the mechanical properties of shale,as a quasi-brittle material. In this study, the effects of microstructure on fracture process zones of Carbonate Dominated (CD) shale and Quartz-Feldspar Dominated (QFD) shale are revealed by semi-circular bend tests combined with digital image correlation. Results indicate that the FPZ shape of CD shale is a fat ellipse and the FPZ shape of QFD shale is a narrow and long ellipse. The average FPZ width and length of CD shales are 4.70 mm and 2.38 mm, while the average FPZ width and length of QFD shales are 3.84 mm and 2.93 mm. The main reason for this phenomenon is the difference of mechanical properties between bedding and rock matrix. The Young's modulus, stiffness, and fracture toughness of the (QFD) shale bedding planes are 42%, 70%, and 50% greater than rock matrix. While these differences are 25%, 35% and 29% respectively in CD shale. The interfacial mechanical contrast between bedding planes and the rock matrix affects the energy distribution during fracture, ultimately governing the elliptical morphology development of fracture process zones (FPZ). Energy dissipation during fracture propagation occurs more readily along the sides of the pre-crack tip in CD shale, leading to a wider and shorter elliptical FPZ. A numerical simulation model based on the combined finite-discrete element method (FDEM) was conducted under conditions consistent with the experimental setup. The simulation results confirm that a high fracture energy has a significant impact on the post-peak performance of the element, making its plastic stage longer and thus generating a larger FPZ. This study provides beneficial insights into the anisotropic behaviors of oil shale.

页岩作为一种准脆性材料，其断裂过程带（FPZ）对其力学性能起着至关重要的作用。通过半圆弧弯曲试验结合数字图像相关，揭示了微观结构对碳酸盐岩页岩（CD）和石英长石页岩（QFD）裂缝过程带的影响。结果表明，CD页岩的FPZ形状为粗椭圆，QFD页岩的FPZ形状为窄长椭圆。CD页岩的平均FPZ宽度和长度分别为4.70 mm和2.38 mm， QFD页岩的平均FPZ宽度和长度分别为3.84 mm和2.93 mm。造成这种现象的主要原因是层理与岩石基质的力学性质不同。页岩层理面的杨氏模量、刚度和断裂韧性分别比岩石基体高42%、70%和50%。而在CD页岩中，这些差异分别为25%、35%和29%。层理面与岩石基质之间的界面力学对比影响了破裂过程中的能量分布，最终控制了破裂过程带的椭圆形态发育。在CD页岩中，裂缝扩展过程中的能量耗散更容易发生在预裂尖端两侧，导致椭圆FPZ更宽、更短。在与实验设置相符的条件下，建立了基于有限-离散元法（FDEM）的数值模拟模型。仿真结果证实，高断裂能对构件峰后性能有显著影响，使其塑性阶段更长，从而产生更大的FPZ。该研究为油页岩的各向异性行为提供了有益的见解。

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引用次数: 0

Locked segment of fault as earthquake barrier: Laboratory and field evidence of preseismic stress drop 作为地震屏障的断层锁断段：震前应力下降的实验室和现场证据

IF 7

Rock Mechanics Bulletin

Pub Date : 2026-07-01 Epub Date: 2025-11-15 DOI: 10.1016/j.rockmb.2025.100275

Chongyuan Zhang , Manchao He , Yifan Wu , Zhigang Tao , Dongjue Fan

Natural fault systems exhibit significant geometric heterogeneity, where locked segments act as strong, unbroken regions that impede fault slip and influence seismic nucleation. This study integrates laboratory triaxial shear experiments on granite samples with field observations from piezomagnetic stress monitoring stations to investigate the rupture dynamics, stress evolution, and precursory characteristics of locked patches. Experimental results reveal four distinct phases of fault slip: elastic deformation, microcrack propagation, stress accumulation, and stress drop/instability. Locked patches exhibit 3–5 times higher peak shear strength than continuous faults, with failure modes transitioning from tensile (low confining pressure) to shear-dominated (high confining pressure). Notably, precursory stress drops lasting tens to hundreds of seconds—significantly longer than smooth fault precursors were observed, offering extended early-warning windows. Field validation from the Qiaoqi station (Longmen Shan Fault Zone) captured 15% stress fluctuations 4 days before the 2013 Lushan earthquake, aligning with laboratory-derived stress-time signatures. These findings provide a mechanistic basis for interpreting crustal stress anomalies as precursors, bridging laboratory-scale physics with natural fault systems to advance earthquake forecasting strategies.

自然断层系统表现出明显的几何非均质性，其中锁定的区段作为强大的未破碎区域，阻碍断层滑动并影响地震成核。本研究将室内三轴剪切实验与压磁地应力监测站的现场观测相结合，研究锁定斑块的破裂动力学、应力演化和前兆特征。实验结果揭示了断层滑动的四个不同阶段：弹性变形阶段、微裂纹扩展阶段、应力积累阶段和应力下降/失稳阶段。锁定斑块的峰值抗剪强度是连续断层的3-5倍，破坏模式由拉伸（低围压）向剪切（高围压）转变。值得注意的是，前兆应力下降持续了几十到几百秒，比观察到的光滑断层前兆长得多，提供了延长的预警窗口。在2013年芦山地震发生前4天，桥旗站（龙门山断裂带）的现场验证捕获了15%的应力波动，与实验室获得的应力-时间特征一致。这些发现为解释地应力异常作为前兆提供了机制基础，将实验室规模的物理与自然断层系统联系起来，以推进地震预报策略。

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引用次数: 0

The frictional sliding properties of antigorite gouge under hydrothermal conditions 热液条件下反长岩泥的摩擦滑动特性

IF 7

Rock Mechanics Bulletin

Pub Date : 2026-04-01 Epub Date: 2025-09-01 DOI: 10.1016/j.rockmb.2025.100244

Shimin Liu , Mengke An , Wenhao Dai , Huiru Lei , Lei Zhang , Yongsheng Zhou , Zekang Yang

As a weak mineral overlying subduction-zone faults, the widespread presence of antigorite can markedly affect subduction-zone dynamics. To better understand the mechanical properties of antigorite-bearing faults, we conducted frictional sliding experiments on antigorite under hydrothermal conditions. The experimental setup involved a constant confining pressure of 100 MPa, a low pore fluid pressure of 30 MPa, and temperatures ranging from 100 °C to 500 °C. We varied the axial loading rate between 0.04, 0.2, and 1.0 μm/s to examine the velocity dependence of the friction coefficient. The results showed that the friction coefficient of antigorite exhibited a significant temperature dependence. Between 100 °C and 400 °C, the friction coefficient decreased from 0.66 to 0.54 as the temperature increased. Above 400 °C, the friction coefficient increased, reaching 0.7. The velocity dependence of antigorite exhibited velocity strengthening (a – b > 0) throughout the entire experimental temperature range (100 °C–500 °C). The impact of pore-fluid pressure on the frictional behavior of antigorite was also significant. Under low pore-fluid pressure (30 MPa), the frictional strength increases above 400 °C, associated with dehydration hardening. In contrast, at high pore fluid pressure, frictional weakening continues at elevated temperatures, indicating that pore fluid pressure plays a crucial role in regulating the frictional stability of antigorite. Our experimental results demonstrate that the pore fluid pressure plays a key role in regulating the temperature-dependent frictional behavior of antigorite, highlighting the need for further investigation under varying fluid pressure conditions.

反长花岗岩作为一种弱矿物覆在俯冲带断裂上，其广泛存在对俯冲带动力学具有显著影响。为更好地了解含反长花岗岩断裂的力学性质，开展了热液条件下反长花岗岩的摩擦滑动实验。实验设置为围压为100 MPa，低孔隙流体压力为30 MPa，温度范围为100℃至500℃。我们将轴向加载速率在0.04、0.2和1.0 μm/s之间变化，以研究摩擦系数与速度的关系。结果表明，反长岩的摩擦系数表现出明显的温度依赖性。在100 ~ 400℃之间，随着温度的升高，摩擦系数从0.66下降到0.54。在400℃以上，摩擦系数增大，达到0.7。在整个实验温度范围内（100℃~ 500℃），反长岩的速度依赖性表现为速度增强（a ~ b > 0）。孔隙流体压力对反长岩摩擦行为的影响也很显著。在低孔隙流体压力（30 MPa）下，摩擦强度在400℃以上增加，与脱水硬化有关。相反，在高孔隙流体压力下，随着温度的升高，摩擦作用持续减弱，表明孔隙流体压力对反长岩的摩擦稳定性起着至关重要的调节作用。我们的实验结果表明，孔隙流体压力在调节反长岩的温度依赖摩擦行为中起着关键作用，强调了在不同流体压力条件下进一步研究的必要性。

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引用次数: 0

Recent advancements for cement grout diffusion mechanisms within rock fractures 岩石裂隙内水泥浆扩散机制研究进展

IF 7

Rock Mechanics Bulletin

Pub Date : 2026-04-01 Epub Date: 2025-08-22 DOI: 10.1016/j.rockmb.2025.100237

Haizhi Zang, Shanyong Wang

Understanding cement grout diffusion in rock fractures is crucial for rock engineering, yet grouting faces significant challenges due to fracture network heterogeneity and grout's complex non-Newtonian rheology. This study critically reviews recent theoretical, experimental, and numerical advancements to comprehensively understand cement grout diffusion mechanisms within rock fractures. It begins by discussing theoretical foundations, encompassing both continuum and particulate views in single fractures, while also highlighting limitations in extending these simplified concepts to fracture networks and defining robust stop criteria. Subsequently, the article details developments in experiments, including novel apparatus and advanced monitoring techniques. These enable controlled observation of grout diffusion in artificial or simulated fractures, providing crucial insights into the impact of fracture complexities (e.g., fracture roughness, two-phase flow) on grout patterns and sealing efficiency. These laboratory tests also inform the development of practical stop criteria by revealing actual grout behaviour under various conditions. Complementary numerical methods offer a distinct advantage by providing dynamic, continuous solutions for complex fracture networks that are otherwise intractable. Collectively, these diverse approaches bridge critical knowledge gaps, from fundamental principles to real-world complexities, and facilitate cross-scale validation. The review concludes by identifying persistent challenges, such as integrating multi-scale descriptions and simulating true field complexities, and outlines future research directions to understand grout diffusion mechanisms.

了解水泥浆液在岩石裂缝中的扩散对岩石工程至关重要，但由于裂缝网络的非均质性和浆液复杂的非牛顿流变性，注浆面临着巨大的挑战。本研究批判性地回顾了最近的理论、实验和数值进展，以全面了解岩石裂缝内水泥灌浆扩散机制。首先讨论了理论基础，包括单个裂缝的连续体和颗粒视图，同时也强调了将这些简化概念扩展到裂缝网络和定义稳健停止标准的局限性。随后，文章详细介绍了实验的发展，包括新的仪器和先进的监测技术。这些技术可以控制观察人工或模拟裂缝中的浆液扩散，为裂缝复杂性（例如裂缝粗糙度、两相流）对浆液模式和密封效率的影响提供重要见解。这些实验室测试还通过揭示各种条件下实际的灌浆行为，为实际停止标准的制定提供信息。互补数值方法具有明显的优势，可以为复杂的裂缝网络提供动态、连续的解决方案。总的来说，这些不同的方法弥合了关键的知识差距，从基本原理到现实世界的复杂性，并促进了跨规模的验证。总结指出了持续存在的挑战，如整合多尺度描述和模拟真实的现场复杂性，并概述了未来的研究方向，以了解浆液扩散机制。

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引用次数: 0

The frictional sliding properties of antigorite gouge under hydrothermal conditions 热液条件下反长岩泥的摩擦滑动特性

IF 7

Rock Mechanics Bulletin

Pub Date : 2026-04-01 Epub Date: 2025-09-01 DOI: 10.1016/j.rockmb.2025.100244

Shimin Liu , Mengke An , Wenhao Dai , Huiru Lei , Lei Zhang , Yongsheng Zhou , Zekang Yang

As a weak mineral overlying subduction-zone faults, the widespread presence of antigorite can markedly affect subduction-zone dynamics. To better understand the mechanical properties of antigorite-bearing faults, we conducted frictional sliding experiments on antigorite under hydrothermal conditions. The experimental setup involved a constant confining pressure of 100 MPa, a low pore fluid pressure of 30 MPa, and temperatures ranging from 100 °C to 500 °C. We varied the axial loading rate between 0.04, 0.2, and 1.0 μm/s to examine the velocity dependence of the friction coefficient. The results showed that the friction coefficient of antigorite exhibited a significant temperature dependence. Between 100 °C and 400 °C, the friction coefficient decreased from 0.66 to 0.54 as the temperature increased. Above 400 °C, the friction coefficient increased, reaching 0.7. The velocity dependence of antigorite exhibited velocity strengthening (a – b > 0) throughout the entire experimental temperature range (100 °C–500 °C). The impact of pore-fluid pressure on the frictional behavior of antigorite was also significant. Under low pore-fluid pressure (30 MPa), the frictional strength increases above 400 °C, associated with dehydration hardening. In contrast, at high pore fluid pressure, frictional weakening continues at elevated temperatures, indicating that pore fluid pressure plays a crucial role in regulating the frictional stability of antigorite. Our experimental results demonstrate that the pore fluid pressure plays a key role in regulating the temperature-dependent frictional behavior of antigorite, highlighting the need for further investigation under varying fluid pressure conditions.

反长花岗岩作为一种弱矿物覆在俯冲带断裂上，其广泛存在对俯冲带动力学具有显著影响。为更好地了解含反长花岗岩断裂的力学性质，开展了热液条件下反长花岗岩的摩擦滑动实验。实验设置为围压为100 MPa，低孔隙流体压力为30 MPa，温度范围为100℃至500℃。我们将轴向加载速率在0.04、0.2和1.0 μm/s之间变化，以研究摩擦系数与速度的关系。结果表明，反长岩的摩擦系数表现出明显的温度依赖性。在100 ~ 400℃之间，随着温度的升高，摩擦系数从0.66下降到0.54。在400℃以上，摩擦系数增大，达到0.7。在整个实验温度范围内（100℃~ 500℃），反长岩的速度依赖性表现为速度增强（a ~ b > 0）。孔隙流体压力对反长岩摩擦行为的影响也很显著。在低孔隙流体压力（30 MPa）下，摩擦强度在400℃以上增加，与脱水硬化有关。相反，在高孔隙流体压力下，随着温度的升高，摩擦作用持续减弱，表明孔隙流体压力对反长岩的摩擦稳定性起着至关重要的调节作用。我们的实验结果表明，孔隙流体压力在调节反长岩的温度依赖摩擦行为中起着关键作用，强调了在不同流体压力条件下进一步研究的必要性。

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