Rock Mechanics Bulletin最新文献

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 : 2026-01-13 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

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 : 2026-01-08 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

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

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 : 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

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

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 : 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

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

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 : 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

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