Rock Mechanics Bulletin最新文献_第3页

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 : 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

Development characteristics and prediction methods of the “three zones” in overlying strata under the 110 mining method 110采矿法下覆岩“三带”发育特征及预测方法

IF 7

Rock Mechanics Bulletin

Pub Date : 2025-08-21 DOI: 10.1016/j.rockmb.2025.100234

Xiaojie Yang , Xuhui Kang , Manchao He , Yajun Wang , Jun Zhang , Zhen Shi , Yuwen Chen

The 110 mining method is a novel coal mining approach that is environmentally friendly. To investigate the movement laws of the overburden strata under the mining conditions of this method, this study systematically analyzed the development characteristics and formation mechanisms of the “three zones” of the overburden strata (caving zone, fractured zone, and flexural subsidence zone). A predictive model for the development height of the “three zones” was established based on the mining damage invariant equation and the pressure arch theory, and a quantitative criterion for the boundary between the caving zone and fractured zone was proposed.To verify the reliability of the model, the 8302 working face of Jinjiazhuang Coal Mine was selected as the research object. A combination of theoretical analysis and on-site monitoring was employed to conduct prediction and in-situ monitoring experiments on the height of the “three zones” and the surface conditions of the goaf. The results show that the relative error between the predicted height of the caving zone by the model and the measured value is +0.38 m, and the relative error for the fractured zone height is −1.55 m, indicating a high prediction accuracy.The predictive model established in this study provides a theoretical basis for the safe and efficient mining as well as the overburden control in the 110 mining method. The research findings have significant engineering application value for promoting the development of green coal mining technologies.

110采煤法是一种环保的新型采煤方法。为研究该方法开采条件下覆岩的移动规律，系统分析了覆岩“三带”（崩落带、破碎带、弯曲沉陷带）的发育特征及形成机理。基于开采损伤不变量方程和压力拱理论，建立了“三带”发育高度的预测模型，提出了崩落带与破碎带边界的定量判据。为验证模型的可靠性，选取金家庄煤矿8302工作面作为研究对象。采用理论分析与现场监测相结合的方法，对采空区“三带”高度及采空区地表状况进行了预测和现场监测实验。结果表明：模型预测崩落带高度与实测值的相对误差为+0.38 m，破碎带高度的相对误差为- 1.55 m，预测精度较高。所建立的预测模型为110采矿法的安全高效开采和覆盖层控制提供了理论依据。研究成果对推动煤炭绿色开采技术的发展具有重要的工程应用价值。

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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 : 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

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 : 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

Influence of bedding orientation on shale damage evolution: A combined in-situ micro-CT and digital volume correlation investigation 层理取向对页岩损伤演化的影响：原位微ct与数字体积相关研究

IF 7

Rock Mechanics Bulletin

Pub Date : 2025-08-15 DOI: 10.1016/j.rockmb.2025.100225

Liang Zhang , Yingjie Li , Liu Yang , Shengxin Liu , Dejun Liu , Bingqian Wang

The bedding structure of shale significantly influences its mechanical anisotropy. However, the meso-scale anisotropic control mechanism of bedding on shale damage evolution remains insufficiently understood. This study employs in-situ uniaxial compression CT scanning experiments, combined with grayscale thresholding and deep learning-based image segmentation, to achieve high-precision 3D reconstructions of shale pore-fracture networks. Additionally, by integrating Digital Volume Correlation (DVC) with image analysis, a cross-scale quantitative characterization and synergistic evaluation are conducted, bridging the evolution of microstructural damage with macroscopic full-field deformation in bedded shale. The results reveal that: (1) The dominant geometric factors influencing the complexity of the shale pore-fracture network during loading vary with bedding orientation: number and spatial distribution dominate for 0° shale, volume and area for 30°/60° shale, and coupled geometric parameters for 90° shale. (2) Displacement and strain fields exhibit distinct characteristics related to the bedding angle: 0° shale shows quasi-uniform deformation dominated by axial compaction; 30° and 60° shales form significant strain concentration bands along bedding planes due to shear slip effects; 90° shale is driven by radial tension, leading to tensile strain localization parallel to the bedding direction. (3) The strain accommodation mechanism in shale transitions with the bedding angle: it shifts from being dominated by matrix compaction and diffuse micro-damage at low angles to being primarily controlled by fracture propagation along bedding planes at high angles. In high-angle bedded shale, pre-existing pores and fractures tend to preferentially act as nucleation sites for damage initiation and strain localization.

页岩的层理结构对其力学各向异性有显著影响。然而，层理对页岩损伤演化的细观各向异性控制机制尚不清楚。本研究采用原位单轴压缩CT扫描实验，结合灰度阈值分割和基于深度学习的图像分割，实现页岩孔隙-裂缝网络的高精度三维重建。此外，通过数字体积相关（Digital Volume Correlation， DVC）与图像分析相结合，进行了跨尺度定量表征和协同评价，架起了层状页岩微观结构损伤演化与宏观全场变形的桥梁。结果表明：(1)影响加载过程中页岩孔隙-裂缝网络复杂性的主要几何因素随层理方向的不同而不同：0°页岩以数量和空间分布为主，30°/60°页岩以体积和面积为主，90°页岩以耦合几何参数为主。(2)位移场和应变场随层理角度变化特征明显：0°页岩表现为轴向压实主导的准均匀变形；30°和60°页岩受剪切滑移影响沿顺层面形成显著的应变集中带；90°页岩受径向张力驱动，拉伸应变局部化方向与顺层方向平行。(3)页岩应变调节机制随层理角度发生转变，由低角度下以基质压实和弥漫性微损伤为主转变为高角度下以裂缝沿层理面扩展为主。在高角度层状页岩中，原有孔隙和裂缝往往优先作为损伤起核和应变局部化的成核场所。

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引用次数: 0

Computational large deformation geomechanics with a focus on the periporomechanics paradigm 计算大变形地质力学，聚焦于孔隙力学范式

IF 7

Rock Mechanics Bulletin

Pub Date : 2025-08-05 DOI: 10.1016/j.rockmb.2025.100224

Xiaoyu Song , Andrew J. Whittle , Shashank Menon

This article presents a state-of-the-art review of computational large deformation geomechanics, focusing on the recently developed periporomechanics (PPM) paradigm. PPM is a nonlocal reformulation of classical continuum poromechanics for geomaterials through peridynamic states and the effective force concept. The governing equations are integral-differential equations in which a length scale is present. In PPM, the porous media, such as geomaterials, are assumed to consist of a finite number of mixed material points which have two types of degrees of freedom, i.e., solid displacement and pore fluid pressure. Consistent with its mathematical formulation, the field equations of PPM are spatially discretized by a hybrid Lagrangian-Eulerian meshless method. Thus, PPM is robust for modeling large deformation and discontinuities in geomaterials. First, we review the recent development of the coupled PPM for modeling coupled solid deformation and fluid flow processes in deformable porous materials. Second, we review the advancement of PPM for modeling large deformation in geomaterials. Third, we present numerical examples to showcase the efficacy of the PPM paradigm for modeling large deformation in variably saturated geomaterials. Finally, we summarize the research needs and present work in PPM for modeling large deformation in geomaterials with applications in geo-hazards such as landslides.

本文介绍了计算大变形地质力学的最新进展，重点介绍了最近发展起来的孔隙力学（PPM）范式。PPM是通过周动力状态和有效力概念对经典连续介质孔隙力学的非局部重新表述。控制方程是存在长度标度的积分微分方程。在PPM中，多孔介质，如岩土材料，被假设由有限数量的混合材料点组成，这些混合材料点具有两种自由度，即固体位移和孔隙流体压力。根据其数学公式，采用拉格朗日-欧拉无网格混合方法对PPM场方程进行空间离散化。因此，PPM对于模拟地质材料中的大变形和不连续性具有鲁棒性。首先，我们回顾了用于模拟可变形多孔材料中固体变形和流体流动耦合过程的耦合PPM的最新进展。其次，我们回顾了PPM在岩土材料大变形建模中的进展。第三，我们提出了数值例子来展示PPM范式在可变饱和岩土材料中模拟大变形的有效性。最后，我们总结了PPM在地质灾害（如滑坡）中用于模拟地质材料大变形的研究需求和目前的工作。

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引用次数: 0

A novel damage model on the acoustic emission characteristics of weakly cemented soft rock under alkaline water-enriched environment 碱性富水环境下弱胶结软岩声发射特征损伤新模型

IF 7

Rock Mechanics Bulletin

Pub Date : 2025-07-18 DOI: 10.1016/j.rockmb.2025.100221

Jiashun Liu , Ni Zhou , Hui Zhou , Zhiyong Zheng , Xuefeng Zhang , Zhiqiang Lv , Jin Yu

Mechanical properties of weakly cemented soft rock (WCSR) under alkaline water-enriched environment are vital to the stability of surrounding rock. The specimens were soaked in various chemical solutions, and a series of experiments including X-ray diffraction (XRD), scanning electron microscopy (SEM) and uniaxial compression tests with acoustic emission (AE) were performed to study AE characteristics, damage evolution characteristics, and corrosion mechanisms of WCSR. The experimental results demonstrated that with the increase of pH values, the upward trend of the accumulative count curves became flatter, the crack propagation rate was more stable, and the energy release was more moderate. Cracks were classified based on AE characteristic parameters RA and AF. The difference between the tension cracks and shear cracks at deionized water and pH = 7 solutions was smaller than 10%, while the difference between the pH = 10 and pH = 12 solutions was 19.6% and 26.54%, respectively. The increase in pH value significantly enhanced the propagation of tensile cracks and the complexity of failure model. Based on Mazars damage model, a novel damage model describing strain softening of WCSR was established by introducing accumulative count, which can better characterize the post-peak strain softening characteristics and damage evolution. In addition, the corrosion mechanism of soft rock under alkaline water-enriched is revealed from a microscopic perspective. The research results will provide significance guiding for deformation control of soft rock roadway and its disaster prevention under alkaline water-enriched environment.

弱胶结软岩在碱性富水环境下的力学特性对围岩的稳定性至关重要。将试样浸泡在不同的化学溶液中，通过x射线衍射（XRD）、扫描电镜（SEM）和单轴声发射（AE）压缩实验，研究WCSR的声发射特征、损伤演化特征以及腐蚀机理。实验结果表明，随着pH值的增加，累计计数曲线的上升趋势变得更加平缓，裂纹扩展速度更加稳定，能量释放更加温和。根据声发射特征参数RA和AF对裂纹进行分类，去离子水和pH = 7溶液下拉伸裂纹和剪切裂纹的差异小于10%，pH = 10和pH = 12溶液下拉伸裂纹和剪切裂纹的差异分别为19.6%和26.54%。pH值的增加显著增强了拉伸裂纹的扩展和破坏模型的复杂性。在Mazars损伤模型的基础上，通过引入累积计数，建立了一种新的描述WCSR应变软化的损伤模型，能更好地表征峰后应变软化特征和损伤演化。此外，从微观角度揭示了富碱性水作用下软岩的腐蚀机理。研究成果将为富碱性水环境下软岩巷道变形控制及防灾提供有意义的指导。

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引用次数: 0

Tensile failure and ductile-to-brittle transition of sandstone under three-dimensional seepage pressure 三维渗流压力下砂岩的拉伸破坏与韧脆转变

IF 7

Rock Mechanics Bulletin

Pub Date : 2025-07-17 DOI: 10.1016/j.rockmb.2025.100222

Xiang Fu , Kecheng Ji , Aiqing Wu , Qiang Xie , Yuxin Ban

After reservoir impoundment, fractures and pores in the rock mass serve as important pathways for seepage, and the resulting fluid pressure can easily trigger engineering issues such as slope instability and dam deformation. To investigate the mechanical properties and failure characteristics of sandstone under hydro-mechanical coupling, triaxial compression tests were conducted under various confining pressures. Combined with acoustic emission monitoring and numerical simulations, this study revealed the internal failure mechanisms and mechanical responses of sandstone in its natural state, after soaking, and under seepage pressure. The experimental results indicate that: (1) with increasing confining pressure, the failure mode of natural and soaked sandstone samples transitions from brittle to ductile, whereas under seepage pressure the failure mode shifts from ductile to brittle; (2) natural sandstone predominantly fails by shear, while soaked sandstone exhibits a mixed failure mode dominated by shear, and under seepage pressure, the samples display a mixed failure mode dominated by splitting; (3) as confining pressure increases, crack propagation is suppressed, leading to a transition from tension-dominated to shear-dominated failure; soaking facilitates stable crack propagation, thereby delaying ultimate failure and exhibiting significant ductile characteristics, whereas seepage pressure accelerates crack development, significantly reducing rock strength and markedly enhancing brittle failure characteristics.

水库蓄水后，岩体中的裂隙和孔隙是渗流的重要途径，由此产生的流体压力容易引发边坡失稳、大坝变形等工程问题。为了研究水-力耦合作用下砂岩的力学特性和破坏特征，进行了不同围压下的三轴压缩试验。结合声发射监测和数值模拟，揭示了砂岩在自然状态、浸泡后和渗流压力作用下的内部破坏机制和力学响应。试验结果表明：(1)随着围压的增加，天然和浸水砂岩试样的破坏模式由脆性向延性转变，而在渗流压力下，破坏模式由延性向脆性转变；(2)天然砂岩主要以剪切破坏为主，浸水砂岩则表现为剪切为主的混合破坏模式，渗流压力下试样表现为劈裂为主的混合破坏模式；(3)随着围压的增大，裂纹扩展受到抑制，由拉伸为主向剪切为主过渡；浸泡有利于裂纹的稳定扩展，从而延缓了最终破坏，呈现出明显的延性特征，而渗流压力则加速了裂纹的发展，显著降低了岩石的强度，显著增强了岩石的脆性破坏特征。

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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 : 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 : 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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