Rock Mechanics Bulletin最新文献_第2页

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 : 2026-04-01 Epub 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 : 2026-04-01 Epub 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

Integration of image and dipole sonic logs for identification of natural fractures and stress-induced anisotropy in Asmari reservoir (A case study, SW Iran) 结合图像和偶极子声波测井识别Asmari储层天然裂缝和应力诱导的各向异性（以伊朗西南部为例）

IF 7

Rock Mechanics Bulletin

Pub Date : 2026-04-01 Epub Date: 2025-08-21 DOI: 10.1016/j.rockmb.2025.100235

Maziar Torkaman , Soheila Bagheri , Mahdi Rastegarnia

Borehole sonic dispersion analysis is a technique that provides valuable insights into the realm of borehole sonic interpretation. This research involves an analysis of shear-wave anisotropy and ultrasonic image logs to differentiate between types of fractures and their orientations. Evaluating fractures relies on core samples and image logs are limited. This highlights the need for a more affordable and efficient way to analyse fractures. A challenge in the wellbore is distinguishing natural fractures from those caused by drilling. Using oil-based mud often makes it hard to find signs indicating the direction of in-situ stress. A new method has been created to reliably identify natural fractures when image logs are insufficient for mapping fracture networks. The cross-dipole data reveals five main zones exhibiting shear-wave splitting. Higher anisotropy is observed at shallower depths, while the deeper interval shows low porosity accompanied by considerable inhomogeneity, highlighting potential areas of concern. The dominant directions of anisotropy are aligned with NW-SE, WNW-ESE, and N-S orientations. Slowness frequency analysis of rotated flexural waves identifies fracture types. Dispersion profiles show natural and induced fractures, with cross-over patterns indicating stress-induced anisotropy. Significant inhomogeneity is observed in the bottom interval, where the differences between maximum and minimum energy level are pronounced. Wider dispersion curves suggest breakouts are slowing high-frequency flexural waves, indicating mechanical damage. The maximum stress direction is determined by the fast-shear azimuth. In conclusion, this study demonstrates that by integrating acoustic shear dispersion, shear anisotropy, Stoneley analysis, and image log data, fractures within the borehole wall can be effectively investigated.

井眼声波频散分析是一种为井眼声波解释领域提供有价值见解的技术。该研究包括对剪切波各向异性和超声图像测井进行分析，以区分裂缝类型及其方向。评估裂缝依赖于岩心样本和图像测井是有限的。这表明需要一种更经济、更有效的方法来分析骨折。如何区分天然裂缝和钻井造成的裂缝，是井筒的一大挑战。使用油基泥浆通常很难找到指示地应力方向的迹象。当图像测井数据不足以绘制裂缝网络时，一种新的方法可以可靠地识别天然裂缝。交叉偶极子数据显示有五个主要的剪切波分裂区。在较浅的深度观察到较高的各向异性，而较深的层段显示低孔隙度并伴有相当大的不均匀性，突出了潜在的关注区域。各向异性的主要方向为NW-SE、WNW-ESE和N-S。旋转弯曲波的慢度频率分析可识别裂缝类型。分散剖面显示天然裂缝和诱导裂缝，交叉模式表明应力诱导的各向异性。在底部区间观察到显著的不均匀性，其中最大和最小能级之间的差异是明显的。更宽的色散曲线表明，爆发正在减缓高频弯曲波，表明机械损伤。最大应力方向由快剪方位角决定。综上所述，通过综合声波剪切频散、剪切各向异性、Stoneley分析和成像测井数据，可以有效地研究井壁内的裂缝。

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引用次数: 0

Integrative solution of stress evolution in overburden roof strata during the coal seam mining by application of complex variable functions methodology 应用复变函数法综合求解煤层开采覆岩顶板应力演化

IF 7

Rock Mechanics Bulletin

Pub Date : 2026-04-01 Epub Date: 2025-08-22 DOI: 10.1016/j.rockmb.2025.100236

Yinkai Li , Hongwei Wang , Zhanbin Zhu , Daixin Deng , Naisheng Jiang

Large-scale roof collapse is a major dynamic hazard threatening the safe coal mine operations. Understanding the deformation and failure characteristics of overburden rock strata, as well as deciphering the stress evolution mechanism of overburden rock structure in mining stopes, is of great theoretical advancement and engineering applications in roof disasters prevention. This study employs a theoretical derivation to systematically analyze the characteristics of overburden roof deformation and caving behavior during the coal seam mining. By modeling the trapezoidal caving zone in the overburden roof strata as a complex functional system, the stress distribution within the caving zone and adjacent intact strata was mathematically characterized. Stress evolution patterns of overburden strata at different caving stages were derived under both elastic and elastoplastic deformation conditions, accompanied by the demarcation of elastic-plastic zones. In addition, the critical length for the first caving and periodic caving of overburden are theoretically determined. To validate the proposed analytical framework, comprehensive numerical simulation and physical model tests are conducted to investigate the overburden roof caving characteristics during coal seam mining. Quantitative comparisons between experimental, numerical results and theoretical analyses were performed in terms of the caving range of roof strata, the critical length for the roof strata caving and stress distribution. The consistencies among different approaches confirms the reliability of the theoretical model, providing a robust foundation for optimizing mining designs and implementing effective roof control strategies.

大面积顶板坍塌是威胁煤矿安全生产的重大动力灾害。了解覆岩岩层的变形破坏特征，破译采场覆岩结构的应力演化机制，对顶板灾害防治具有重要的理论意义和工程应用价值。本文采用理论推导的方法，系统分析了煤层开采过程中覆岩顶板的变形和冒落特性。通过将覆岩顶板岩层中的梯形崩落带建模为一个复杂的功能系统，对崩落带及其相邻完整岩层内的应力分布进行了数学表征。推导了不同垮落阶段覆岩在弹塑性和弹塑性变形条件下的应力演化规律，并划分了弹塑性带。此外，从理论上确定了覆岩第一次崩落和周期性崩落的临界长度。为了验证所提出的分析框架，对煤层开采过程中覆岩顶板冒落特性进行了综合数值模拟和物理模型试验研究。在顶板垮落范围、顶板垮落临界长度及应力分布等方面，将实验结果、数值结果与理论分析进行了定量比较。不同方法之间的一致性证实了理论模型的可靠性，为优化采矿设计和实施有效的顶板控制策略提供了坚实的基础。

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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 : 2026-04-01 Epub 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

Integrative solution of stress evolution in overburden roof strata during the coal seam mining by application of complex variable functions methodology 应用复变函数法综合求解煤层开采覆岩顶板应力演化

IF 7

Rock Mechanics Bulletin

Pub Date : 2026-04-01 Epub Date: 2025-08-22 DOI: 10.1016/j.rockmb.2025.100236

Yinkai Li , Hongwei Wang , Zhanbin Zhu , Daixin Deng , Naisheng Jiang

Large-scale roof collapse is a major dynamic hazard threatening the safe coal mine operations. Understanding the deformation and failure characteristics of overburden rock strata, as well as deciphering the stress evolution mechanism of overburden rock structure in mining stopes, is of great theoretical advancement and engineering applications in roof disasters prevention. This study employs a theoretical derivation to systematically analyze the characteristics of overburden roof deformation and caving behavior during the coal seam mining. By modeling the trapezoidal caving zone in the overburden roof strata as a complex functional system, the stress distribution within the caving zone and adjacent intact strata was mathematically characterized. Stress evolution patterns of overburden strata at different caving stages were derived under both elastic and elastoplastic deformation conditions, accompanied by the demarcation of elastic-plastic zones. In addition, the critical length for the first caving and periodic caving of overburden are theoretically determined. To validate the proposed analytical framework, comprehensive numerical simulation and physical model tests are conducted to investigate the overburden roof caving characteristics during coal seam mining. Quantitative comparisons between experimental, numerical results and theoretical analyses were performed in terms of the caving range of roof strata, the critical length for the roof strata caving and stress distribution. The consistencies among different approaches confirms the reliability of the theoretical model, providing a robust foundation for optimizing mining designs and implementing effective roof control strategies.

大面积顶板坍塌是威胁煤矿安全生产的重大动力灾害。了解覆岩岩层的变形破坏特征，破译采场覆岩结构的应力演化机制，对顶板灾害防治具有重要的理论意义和工程应用价值。本文采用理论推导的方法，系统分析了煤层开采过程中覆岩顶板的变形和冒落特性。通过将覆岩顶板岩层中的梯形崩落带建模为一个复杂的功能系统，对崩落带及其相邻完整岩层内的应力分布进行了数学表征。推导了不同垮落阶段覆岩在弹塑性和弹塑性变形条件下的应力演化规律，并划分了弹塑性带。此外，从理论上确定了覆岩第一次崩落和周期性崩落的临界长度。为了验证所提出的分析框架，对煤层开采过程中覆岩顶板冒落特性进行了综合数值模拟和物理模型试验研究。在顶板垮落范围、顶板垮落临界长度及应力分布等方面，将实验结果、数值结果与理论分析进行了定量比较。不同方法之间的一致性证实了理论模型的可靠性，为优化采矿设计和实施有效的顶板控制策略提供了坚实的基础。

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引用次数: 0

Effects of loading rates and mine water immersion on the mechanical characteristics of coal under Brazilian test conditions 巴西试验条件下加载速率和矿井浸水对煤力学特性的影响

IF 7

Rock Mechanics Bulletin

Pub Date : 2026-04-01 Epub Date: 2025-07-17 DOI: 10.1016/j.rockmb.2025.100223

Xiaobin Li , Gan Feng , Xu Wang , Jianxiong Yang , Yu Zhao , Guifeng Wang , Mingli Xiao , Chunyu Gao , Huaizhong Liu

The mechanical properties of coal pillars are crucial for evaluating the stability of underground water reservoirs in coal mines. This article examines the fracture mechanical behavior of coal in response to mine water immersion, layer direction, and loading rate. Eight types of specimens were studied, featuring inclination angles between the applied force and the bedding plane of 0°, 15°, 30°, 45°, 60°, 75°, 90°, and the Divider type. The loading rates (V) tested were 0.005 kN/s, 0.02 kN/s, 0.05 kN/s, and 0.1 kN/s. The results indicated that after immersion in mine water for 30 days, the Brazilian splitting strength (BSS), splitting modulus (E_m), and absorbed energy (U_a) of coal decreased by 51.35%, 52.37%, and 44.60%, respectively, compared to the non-immersion samples. The primary reason for this phenomenon is that the production rate of micropores and small pores resulting from mine water immersion surpasses their conversion rate to mesopores and macropores. This imbalance leads to the fragmentation of the internal structure of coal and the interconnection of pore fracture zones, thereby significantly weakening its bearing capacity. It has been observed that the relative proportions of failure mechanisms along and across the bedding plane directly influence the variations in coal mechanical properties at different θ values. Additionally, BSS, E_m, and U_a of coal gradually increase with an increase in loading rate, which is due to the reduced duration of coal damage development and evolution, subsequently lowering the probability of activating weak structures.

煤柱的力学特性是评价煤矿地下水库稳定性的关键。本文研究了煤的断裂力学行为对矿井浸水、层向和加载速率的响应。8种试样的受力与层理面倾角分别为0°、15°、30°、45°、60°、75°、90°和分隔板型。试验加载速率(V)分别为0.005 kN/s、0.02 kN/s、0.05 kN/s和0.1 kN/s。结果表明：煤在矿井水中浸泡30 d后，其巴西劈裂强度（BSS）、劈裂模量（Em）和吸收能（Ua）分别比未浸泡的煤降低51.35%、52.37%和44.60%；造成这一现象的主要原因是由于矿井水浸产生的微孔和小孔的生成速度超过了它们向中孔和大孔的转化速度。这种不平衡导致煤的内部结构破碎，孔隙破碎带相互连接，从而显著削弱其承载能力。在不同θ值下，沿顺层面和顺层面破坏机制的相对比例直接影响煤的力学性能变化。随着加载速率的增加，煤的BSS、Em和Ua逐渐增大，这是由于煤损伤发展演化的持续时间缩短，从而降低了脆弱结构激活的概率。

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引用次数: 0

Effects of loading rates and mine water immersion on the mechanical characteristics of coal under Brazilian test conditions 巴西试验条件下加载速率和矿井浸水对煤力学特性的影响

IF 7

Rock Mechanics Bulletin

Pub Date : 2026-04-01 Epub Date: 2025-07-17 DOI: 10.1016/j.rockmb.2025.100223

Xiaobin Li , Gan Feng , Xu Wang , Jianxiong Yang , Yu Zhao , Guifeng Wang , Mingli Xiao , Chunyu Gao , Huaizhong Liu

The mechanical properties of coal pillars are crucial for evaluating the stability of underground water reservoirs in coal mines. This article examines the fracture mechanical behavior of coal in response to mine water immersion, layer direction, and loading rate. Eight types of specimens were studied, featuring inclination angles between the applied force and the bedding plane of 0°, 15°, 30°, 45°, 60°, 75°, 90°, and the Divider type. The loading rates (V) tested were 0.005 kN/s, 0.02 kN/s, 0.05 kN/s, and 0.1 kN/s. The results indicated that after immersion in mine water for 30 days, the Brazilian splitting strength (BSS), splitting modulus (E_m), and absorbed energy (U_a) of coal decreased by 51.35%, 52.37%, and 44.60%, respectively, compared to the non-immersion samples. The primary reason for this phenomenon is that the production rate of micropores and small pores resulting from mine water immersion surpasses their conversion rate to mesopores and macropores. This imbalance leads to the fragmentation of the internal structure of coal and the interconnection of pore fracture zones, thereby significantly weakening its bearing capacity. It has been observed that the relative proportions of failure mechanisms along and across the bedding plane directly influence the variations in coal mechanical properties at different θ values. Additionally, BSS, E_m, and U_a of coal gradually increase with an increase in loading rate, which is due to the reduced duration of coal damage development and evolution, subsequently lowering the probability of activating weak structures.

煤柱的力学特性是评价煤矿地下水库稳定性的关键。本文研究了煤的断裂力学行为对矿井浸水、层向和加载速率的响应。8种试样的受力与层理面倾角分别为0°、15°、30°、45°、60°、75°、90°和分隔板型。试验加载速率(V)分别为0.005 kN/s、0.02 kN/s、0.05 kN/s和0.1 kN/s。结果表明：煤在矿井水中浸泡30 d后，其巴西劈裂强度（BSS）、劈裂模量（Em）和吸收能（Ua）分别比未浸泡的煤降低51.35%、52.37%和44.60%；造成这一现象的主要原因是由于矿井水浸产生的微孔和小孔的生成速度超过了它们向中孔和大孔的转化速度。这种不平衡导致煤的内部结构破碎，孔隙破碎带相互连接，从而显著削弱其承载能力。在不同θ值下，沿顺层面和顺层面破坏机制的相对比例直接影响煤的力学性能变化。随着加载速率的增加，煤的BSS、Em和Ua逐渐增大，这是由于煤损伤发展演化的持续时间缩短，从而降低了脆弱结构激活的概率。

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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 : 2026-04-01 Epub 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

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 : 2026-04-01 Epub 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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