Rock Mechanics Bulletin最新文献

From lab forces to field lifespans: How rock and operating parameters govern TBM disc cutter wear 从实验室力到现场寿命：岩石和操作参数如何控制TBM盘刀磨损

IF 7

Rock Mechanics Bulletin

Pub Date : 2025-12-02 DOI: 10.1016/j.rockmb.2025.100278

Ehsan Mohtarami , Amin Hekmatnejad , Georg H. Erharter , Alvaro Pena

Tunnel boring machines (TBMs) are considered a reliable and fast method for boring long tunnels. However, the wear and failure of disc cutters in hard rock influences the efficiency of equipment, ultimate timeline, and project cost. Therefore, estimating the cutter life under different geomechanical conditions is crucial for TBM manufacturers and tunnel engineers. This study investigates the influence of geomechanical factors, including elastic modulus (E), uniaxial compressive strength (σ_c), confining stresses, and TBM operational parameters such as penetration rate (P) and disc cutter inclination angle (ϕ), on disc cutter wear using the explicit finite element method. The results revealed that the uniaxial compressive strength, disc cutter inclination angle, rock elastic modulus, and confining stresses, in that order, had the greatest impact on the cutter wear rate. Such that an increase in compressive strength from 31 MPa to 137.9 MPa caused a 2.4-fold reduction in cutter life. Meanwhile, the cutter life in the rock without confining stress was only 15% greater than in the sample under 15 MPa of confining stress. Additionally, to achieve the most optimal and economical drilling conditions, the penetration depth of the disc cutters should be optimized based on the existing conditions. Since the installation location of the disc cutters, their spacing and rotational trajectory significantly influence wear levels, a full-scale simulation of a TBM is conducted according to a real case study. The comparison of results indicated that the proposed method has high capability in estimating the cutter life under various geomechanical conditions.

隧道掘进机被认为是一种可靠、快速的长隧道掘进方法。然而，盘式切削齿在硬岩中的磨损和失效会影响设备的效率、最终时间和项目成本。因此，估算刀具在不同地质力学条件下的寿命对于TBM制造商和隧道工程师来说至关重要。采用显式有限元法研究了弹性模量(E)、单轴抗压强度（σc）、围应力、钻速(P)、刀盘倾角（φ）等地质力学因素对刀盘磨损的影响。结果表明，单轴抗压强度、圆盘刀倾角、岩石弹性模量、围应力对刀磨损率影响最大；因此，抗压强度从31 MPa增加到137.9 MPa，导致刀具寿命减少2.4倍。同时，在无围应力条件下，切削齿在岩石中的寿命仅比在15 MPa围应力条件下的切削齿寿命长15%。此外，为了获得最优、最经济的钻井条件，应在现有条件的基础上对盘式刀具的入孔深度进行优化。由于盘式切削齿的安装位置、间距和旋转轨迹对磨损程度有显著影响，因此根据实际案例对TBM进行了全尺寸仿真。结果表明，该方法对各种地质力学条件下的刀具寿命估算具有较高的能力。

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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 : 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

A method for evaluating the stability of roadway surrounding rock based on a modified damage evolution characteristic model considering rock mass residual strength and 3D DEM 基于改进的岩体残余强度损伤演化特征模型和三维DEM的巷道围岩稳定性评价方法

IF 7

Rock Mechanics Bulletin

Pub Date : 2025-11-06 DOI: 10.1016/j.rockmb.2025.100271

Shengrong Xie , Yuxuan Wang , Yiyi Wu , Jian Yang , Zhigen Wang

Repetitive mining in multi-seam conditions induces cumulative damage to surrounding rock, significantly increasing the risk of roadway instability. Taking the roadway in the extra-thick coal seam fully mechanized top-coal caving face as the research object, this study innovatively developed a modified damage evolution characteristic model that considers the residual strength of rock mass to quantify the regulatory effect of damage variable D on roof fracture span: damage to the main roof reduces the initial and periodic fracture spans, significantly increasing the probability of slippage and rotational instability of the voussoir beam structure. On this basis, a three-dimensional discrete element method (3D DEM) model was established, and orthogonal tests were designed to reveal the coupling mechanism of the spatial position of fracture lines and coal pillar width on rock mass damage. The results show that when the coal pillar width increases from 8 m to 16 m, the peak stress at the roadway ribs decreases by 26.5%–43.3%, and the influence range of the second invariant of the deviatoric stress tensor (J₂) shrinks. The attenuation of stress gradient leads to a decrease in the evolution rate of plastic damage with increasing coal pillar width, while the position of the fracture line has a weak regulatory effect on the stress-plastic response of the coal pillar. The results of theoretical analysis and 3D DEM simulations have effectively guided on-site engineering practice.

多煤层条件下的重复开采对围岩造成累积损伤，显著增加了巷道失稳风险。以特厚煤层综放工作面巷道为研究对象，创新性地建立了考虑岩体残余强度的改进损伤演化特征模型，量化损伤变量D对顶板断裂跨度的调节作用：主顶板的破坏降低了初始断裂跨度和周期断裂跨度，显著增加了夹层梁结构发生滑移和旋转失稳的概率。在此基础上，建立三维离散元法（3D DEM）模型，设计正交试验揭示裂隙线空间位置与煤柱宽度对岩体损伤的耦合机理。结果表明：当煤柱宽度从8 m增加到16 m时，巷道肋处峰值应力减小26.5% ~ 43.3%，偏应力张量第二不变量（J2）的影响范围缩小；应力梯度的衰减导致塑性损伤演化速率随煤柱宽度的增大而减小，而裂隙线位置对煤柱应力-塑性响应的调节作用较弱。理论分析和三维DEM模拟结果有效地指导了现场工程实践。

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引用次数: 0

Thermo-mechanical coupling in cracked granite: Influence of crack inclination on fracture behavior and temperature evolution 裂纹花岗岩的热-力耦合：裂纹倾角对断裂行为和温度演化的影响

IF 7

Rock Mechanics Bulletin

Pub Date : 2025-11-04 DOI: 10.1016/j.rockmb.2025.100272

Chenrui Huang , Chaomin Mu , Fei Wang , Yangyong Wu

Crack inclination angle (α) plays a critical role in the dynamic failure and thermo-mechanical coupling of granite, which is vital for rockburst monitoring and prevention. In this study, granite specimens with various prefabricated crack inclinations (α = 0°, 30°, 60°, 90°) were tested using a split Hopkinson pressure bar (SHPB) system. Transient crack tip temperatures were monitored in real time by high-speed infrared thermography, and crack propagation was analyzed using digital image correlation (DIC). The results show that: 1) Propagation mode and mechanical properties: Increasing crack inclination causes a transition from pure tensile propagation to tension–shear mixed modes. At α = 60°, enhanced shear promotes branching cracks, while at α = 90°, crack closure suppresses propagation and induces localized damage. 2) Strength characteristics: Peak stress exhibits a “U-shaped” trend with respect to α, reaching the lowest value at α = 60°. 3) Thermal response: Crack tip temperature rise is strongly dependent on inclination. The maximum rise (up to 9.266 °C) occurs at α = 30° and 60° due to pronounced tension-shear coupling and frictional slip, whereas α = 0° and 90° show smaller increases. 4) Two-stage temperature evolution: Before peak stress, ∼80% of the temperature rise originates from plastic work; after peak stress, crack slip and friction dominate, leading to accelerated heating. 5) Crack tip temperature rise serves as a sensitive indicator of local energy concentration and disaster risk, providing theoretical support for monitoring and prevention strategies in deep mining.

裂缝倾角（α）在花岗岩的动力破坏和热-力耦合过程中起着关键作用，对岩爆监测和防治具有重要意义。采用分离式霍普金森压杆（SHPB）系统对具有不同预制裂纹倾角（α = 0°、30°、60°、90°）的花岗岩试件进行了试验。利用高速红外热像仪实时监测瞬态裂纹尖端温度，并利用数字图像相关技术分析裂纹扩展过程。结果表明：1)裂纹扩展模式与力学性能：增大裂纹倾角可使裂纹从纯拉伸扩展模式向拉伸-剪切混合模式转变；在α = 60°时，增强的剪切促进了裂纹的分支，而在α = 90°时，裂纹闭合抑制了裂纹的扩展并引起局部损伤。2)强度特征：峰值应力相对于α呈“u”型趋势，在α = 60°处达到最低值。3)热响应：裂纹尖端温升与倾角密切相关。在α = 30°和60°时，由于明显的拉伸-剪切耦合和摩擦滑移，温度最大上升（高达9.266°C），而α = 0°和90°时，温度的上升幅度较小。4)两阶段温度演变：在峰值应力之前，~ 80%的温升来自塑性工作；峰值应力过后，裂纹滑移和摩擦起主导作用，导致升温加速。5)裂缝尖端温升是局部能量集中和灾害风险的敏感指标，为深部开采的监测和预防策略提供理论支持。

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引用次数: 0

Fast marching method-based bent-ray tracing for three-dimensional velocity imaging in mines 基于快速行军法的弯曲射线追踪矿井三维速度成像

IF 7

Rock Mechanics Bulletin

Pub Date : 2025-10-25 DOI: 10.1016/j.rockmb.2025.100262

Jie Yang , Xueyi Shang , Linghao Liu , Yi Wang , Xibing Li

Three-dimensional (3D) seismic velocity imaging is crucial for understanding rock mass stress and structures in mining. Conventional straight-ray tomography suffers from ray-path mismatches with true wavefield propagation in complex media, leading to reduced velocity model accuracy. To address this, we propose a 3D velocity imaging method that integrates the Fast Marching Method (FMM) for bent-ray tracing with the Algebraic Reconstruction Technique (ART) for velocity inversion. The proposed approach was validated through checkerboard tests, recovery tests, and laboratory Lead-Break experiments. Results show that FMM-based ray tracing significantly improves inversion accuracy, achieving root-mean-square (RMS) travel-time residuals of 1.39 ms and 28.66 ms in recovery and field tests, corresponding to reductions of 76.6% and 18.6% compared with straight ray tracing-based methods. Application in the Yongshaba mine, Guizhou Province, China, revealed a distinct low-velocity zone surrounded by high-velocity regions, which is consistent with mining activities and excavation plans. This study demonstrates that the FMM-ART framework provides a robust and accurate tool for mine-scale velocity imaging, with implications for monitoring stress evolution, improving safety, and potential integration with real-time monitoring.

三维地震速度成像是了解矿山岩体应力和结构的重要手段。传统的直线层析成像在复杂介质中存在射线路径与真实波场传播不匹配的问题，导致速度模型精度降低。为了解决这个问题，我们提出了一种3D速度成像方法，该方法将用于弯曲射线追踪的快速推进方法（FMM）与用于速度反演的代数重建技术（ART）相结合。该方法通过棋盘测试、回收测试和实验室断线实验进行了验证。结果表明，基于fmm的射线追踪方法显著提高了反演精度，在采收率和现场测试中，RMS的走时残差分别为1.39 ms和28.66 ms，与基于直线射线追踪方法相比，分别降低了76.6%和18.6%。在贵州永沙坝矿的应用显示出明显的低速带被高速带包围，这与采矿活动和开挖计划相一致。该研究表明，FMM-ART框架为矿山尺度速度成像提供了一个强大而准确的工具，对监测应力演化、提高安全性以及与实时监测的潜在集成具有重要意义。

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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 : 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

Investigation of shale fracture behavior with different bedding properties based on discrete element method 基于离散元法的不同层理性质页岩破裂行为研究

IF 7

Rock Mechanics Bulletin

Pub Date : 2025-09-06 DOI: 10.1016/j.rockmb.2025.100243

Dubo Wang , Jinyu Dong , Dongqiao Liu , Xiangjun Chen , Hai Zhong , Mijia Yang , Hongjian Wang

The interaction between cemented laminae and induced fractures plays a critical role in hydraulic fracture propagation within laminated shale reservoirs. By combining mode-I fracture mechanics experiment conducted on semi-circular bend (SCB) specimens of black carbonaceous shale from the marine Longmaxi Formation with numerical simulations, this study systematically investigates the effects of three key geological parameters: (1) bond strength, (2) vein stiffness, and (3) approach angle on fracture propagation characteristics. The key findings are summarized as follows: (1) Increasing the parallel bond strength promotes fracture crossing behavior. When the vein fracture toughness was reduced to 0.3, 0.2, and 0.1 times that of the shale matrix, fractures exhibited increased deflection tendency along the vein, creating longer stepped propagation paths. (2) For stiffer veins, induced fracture divert into the vein and propagate over longer distances; Additionally, more micro-cracks form within the vein before fracture-vein interaction occurs. (3) Fracture-vein interaction exhibits significant angular dependence: At approach angles between 60° and 90°, fractures predominantly penetrated laminae without deflection; Below 60°, fractures initially diverted into the vein but subsequently re-entered the matrix before reaching the vein terminus. This bifurcation pattern closely resembles laboratory observations of weakly cemented or pre-damaged vein specimens.

胶结层与诱导裂缝的相互作用对层状页岩储层水力裂缝的扩展起着至关重要的作用。通过对海相龙马溪组黑色碳质页岩半圆形弯曲（SCB）试样进行i型断裂力学实验与数值模拟相结合，系统研究了3个关键地质参数(1)黏结强度、(2)脉体刚度、(3)进近角对裂缝扩展特征的影响。主要研究结果如下：(1)增加平行粘结强度可促进断裂交叉行为。当岩脉断裂韧性降低到页岩基质的0.3、0.2和0.1倍时，裂缝沿岩脉的挠曲倾向增加，形成了更长的阶梯扩展路径。(2)对于较硬的矿脉，诱导断裂向矿脉内转移并传播较长距离；此外，在裂隙-脉相互作用发生之前，更多的微裂纹在脉内形成。(3)缝脉相互作用表现出明显的角度依赖性：在接近角为60°~ 90°时，裂缝主要穿透片层而不发生偏转；在60°以下，骨折最初转向静脉，但随后在到达静脉末端之前重新进入基质。这种分叉模式与实验室观察到的弱胶结或预损伤静脉标本非常相似。

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引用次数: 0

Investigation of shale fracture behavior with different bedding properties based on discrete element method 基于离散元法的不同层理性质页岩破裂行为研究

IF 7

Rock Mechanics Bulletin

Pub Date : 2025-09-06 DOI: 10.1016/j.rockmb.2025.100243

Dubo Wang , Jinyu Dong , Dongqiao Liu , Xiangjun Chen , Hai Zhong , Mijia Yang , Hongjian Wang

The interaction between cemented laminae and induced fractures plays a critical role in hydraulic fracture propagation within laminated shale reservoirs. By combining mode-I fracture mechanics experiment conducted on semi-circular bend (SCB) specimens of black carbonaceous shale from the marine Longmaxi Formation with numerical simulations, this study systematically investigates the effects of three key geological parameters: (1) bond strength, (2) vein stiffness, and (3) approach angle on fracture propagation characteristics. The key findings are summarized as follows: (1) Increasing the parallel bond strength promotes fracture crossing behavior. When the vein fracture toughness was reduced to 0.3, 0.2, and 0.1 times that of the shale matrix, fractures exhibited increased deflection tendency along the vein, creating longer stepped propagation paths. (2) For stiffer veins, induced fracture divert into the vein and propagate over longer distances; Additionally, more micro-cracks form within the vein before fracture-vein interaction occurs. (3) Fracture-vein interaction exhibits significant angular dependence: At approach angles between 60° and 90°, fractures predominantly penetrated laminae without deflection; Below 60°, fractures initially diverted into the vein but subsequently re-entered the matrix before reaching the vein terminus. This bifurcation pattern closely resembles laboratory observations of weakly cemented or pre-damaged vein specimens.

胶结层与诱导裂缝的相互作用对层状页岩储层水力裂缝的扩展起着至关重要的作用。通过对海相龙马溪组黑色碳质页岩半圆形弯曲（SCB）试样进行i型断裂力学实验与数值模拟相结合，系统研究了3个关键地质参数(1)黏结强度、(2)脉体刚度、(3)进近角对裂缝扩展特征的影响。主要研究结果如下：(1)增加平行粘结强度可促进断裂交叉行为。当岩脉断裂韧性降低到页岩基质的0.3、0.2和0.1倍时，裂缝沿岩脉的挠曲倾向增加，形成了更长的阶梯扩展路径。(2)对于较硬的矿脉，诱导断裂向矿脉内转移并传播较长距离；此外，在裂隙-脉相互作用发生之前，更多的微裂纹在脉内形成。(3)缝脉相互作用表现出明显的角度依赖性：在接近角为60°~ 90°时，裂缝主要穿透片层而不发生偏转；在60°以下，骨折最初转向静脉，但随后在到达静脉末端之前重新进入基质。这种分叉模式与实验室观察到的弱胶结或预损伤静脉标本非常相似。

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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 : 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

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 : 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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