International Journal of Rock Mechanics and Mining Sciences最新文献_第5页

Parametric calibration in bonded block models for simulating mechanical behaviours of intact rocks using machine learning 用机器学习模拟完整岩石力学行为的粘结块模型参数校准

IF 7.5 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2026-01-07 DOI: 10.1016/j.ijrmms.2026.106400

Fengchang Bu , Ruoshen Lin , Michel Jaboyedoff , Wei Liu , Lei Xue

Despite widespread adoption of the bonded block model (BBM) in modelling intact rocks, the calibration of BBM modelling parameters remains a significant challenge, undermining the trustworthiness of BBM-simulated results. Existing trial-and-error and sensitivity analyses for calibration suffer from inefficiency, subjectivity, and difficulty in establishing the high-dimensional and nonlinear complex mapping from modelling parameters to modelled properties in BBM. To address this issue, built on BBM-based universal distinct element code (UDEC), we employed machine learning to clarify this complex mapping. A comprehensive numerical database with 3456 UDEC simulations was constructed for training machine learning models, followed by the selection of the optimal machine learning models by comparing their predictive performances. Subsequently, we collected experimental data from 99 rock types that served as modelled properties to be input into the selected trained machine learning models. Through an inversion by integrating grid search, the corresponding modelling parameters could be output, that is, the machine learning–calibrated modelling parameters. They were further imported into UDEC to perform another 1485 simulations to validate their reliability and robustness. It was also found that both lithology and block size affect calibration accuracy differently across modelled properties. In applying the framework, specific rock model configuration may be considered when establishing the numerical database, including the constitutive laws of blocks and contacts and specific rock structure. This study provides an effective solution for parametric calibration in BBM, advancing more reliable use of BBM in scientific and engineering contexts.

尽管结合块体模型（BBM）在完整岩石建模中被广泛采用，但BBM建模参数的校准仍然是一个重大挑战，这破坏了BBM模拟结果的可信度。现有的试错法和灵敏度分析存在效率低、主观性强、难以建立从建模参数到建模属性的高维非线性复杂映射等问题。为了解决这个问题，我们基于基于bbm的通用不同元素代码（UDEC），使用机器学习来澄清这个复杂的映射。构建了包含3456个UDEC模拟的综合数值数据库，用于训练机器学习模型，并通过比较其预测性能选择最优的机器学习模型。随后，我们收集了99种岩石类型的实验数据，作为建模属性，输入到选定的训练有素的机器学习模型中。通过积分网格搜索进行反演，可以输出相应的建模参数，即机器学习标定的建模参数。将它们进一步导入UDEC进行另外1485次模拟，以验证其可靠性和鲁棒性。还发现岩性和块体大小对不同建模属性的校准精度影响不同。在应用该框架时，在建立数值数据库时可以考虑特定的岩石模型配置，包括块体和接触体的本构规律以及特定的岩石结构。该研究为BBM的参数校准提供了有效的解决方案，促进了BBM在科学和工程环境中更可靠的使用。

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引用次数: 0

Influence of rock creep on the performance of lined caverns under cyclic pressurization and hydrogen embrittlement 循环加压和氢脆作用下岩石蠕变对衬砌洞室性能的影响

IF 7.5 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2026-01-07 DOI: 10.1016/j.ijrmms.2026.106401

Chenxi Zhao , Haiyang Yu , Zixin Zhang , Qinghua Lei

Lined rock cavern (LRC) technology, known for its remarkable geographical flexibility, stands out as a promising and cost-effective approach to underground hydrogen storage. However, since these caverns are often built in complex geological settings and designed for prolonged operation, evaluating their long-term stability is crucial, which should take into account both the creep of rock masses under fatigue loading and the degradation of the steel lining under hydrogen embrittlement (HE). In this paper, we present a comprehensive numerical analysis of LRCs within fractured rock masses, incorporating the effects of time-dependent viscoelastic deformation in the host rock and HE processes in the steel lining under cyclic pressurization. A novel two-dimensional multiscale model is developed that captures the interactions between the LRC structure and the surrounding fractured rocks to assess the damage and degradation of concrete, rock, and steel components in the LRC system. Our framework uniquely integrates rock viscoelasticity and steel hydrogen embrittlement mechanisms, providing a quantitative means to evaluate the long-term mechanical–chemical interactions. The findings demonstrate that the rock’s viscoelastic behavior significantly impacts the time-dependent integrity of the LRC, with damage progressively accumulating during prolonged operation. Additionally, damage evolution in the concrete lining and rock mass, along with steel degradation, are strongly influenced by pre-existing fractures in the rock mass. While small relaxation times in the viscoelastic response lead to rapid system stabilization, moderate relaxation times can trigger time-dependent stress redistribution and further damage progression. The results also highlight the important effect of HE on LRC performance, especially when the surrounding rock mass is characterized by the presence of interconnected fractures. The insights gained in this study are critical to optimizing the design and ensuring the long-term safe operation of LRCs in the context of sustainable underground hydrogen storage.

内衬岩洞（LRC）技术以其卓越的地理灵活性而闻名，是一种具有前景和成本效益的地下储氢方法。然而，由于这些洞穴通常建在复杂的地质环境中，并且设计用于长时间运行，因此评估它们的长期稳定性至关重要，这应该考虑到疲劳载荷下岩体的蠕变和氢脆（HE）作用下钢衬砌的退化。在本文中，我们对裂隙岩体中的lrc进行了全面的数值分析，考虑了宿主岩石中随时间变化的粘弹性变形和循环加压下钢衬砌中的HE过程的影响。开发了一种新的二维多尺度模型，该模型捕获了LRC结构与周围裂隙岩石之间的相互作用，以评估LRC系统中混凝土，岩石和钢构件的损伤和退化。我们的框架独特地集成了岩石粘弹性和钢氢脆机制，为评估长期的机械-化学相互作用提供了定量手段。研究结果表明，岩石的粘弹性行为显著影响LRC的随时间变化的完整性，随着作业时间的延长，损伤会逐渐累积。此外，混凝土衬砌和岩体的损伤演变以及钢的退化受到岩体中预先存在的裂缝的强烈影响。虽然粘弹性响应中的小松弛时间会导致系统快速稳定，但适度的松弛时间会引发随时间变化的应力重新分布和进一步的损伤进展。结果还强调了HE对LRC性能的重要影响，特别是当围岩存在相互连接的裂缝时。在可持续地下储氢的背景下，本研究获得的见解对于优化设计和确保lrc的长期安全运行至关重要。

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引用次数: 0

Identification of elastic constants of transversely isotropic rocks using strain measurements from a single inclined specimen 横向各向同性岩石的弹性常数的识别用应变测量从一个单一的倾斜试样

IF 7.5 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2026-01-07 DOI: 10.1016/j.ijrmms.2026.106399

Youn-Kyou Lee , S. Pietruszczak

The elastic behavior of transversely isotropic rocks is governed by five independent constants. Conventional methods for measuring these elastic constants typically involve uniaxial compression tests on three specimens sampled at different inclinations with respect to the isotropy plane. However, this approach may introduce errors due to specimen heterogeneity. In this study, three sets of simple inversion formulas are derived to determine five elastic constants from strain data obtained during hydrostatic compression followed by an increment of axial stress applied to a single inclined specimen. Each of these three sets includes an identical equation for the shear modulus and a distinct matrix equation for the remaining four elastic constants. Although these matrix equations differ in appearance, they are mathematically equivalent and yield identical solutions. To facilitate coordinate transformation, the Mehrabadi-Cowin notation was employed, in which the strain and stress states are represented as first-order tensors in a six-dimensional space, and the corresponding compliance matrix is treated as a second-order tensor in the same space. The input data for the proposed inversion formulas consist of strain measurements taken in a coordinate system aligned with the strike and dip directions of the isotropy plane. If the orientation of the isotropy plane can be inferred from the strain data, then strain measurements obtained in an arbitrary coordinate system can also be used as input. Illustrative examples are provided to demonstrate the accuracy and practical relevance of the proposed approach.

横向各向同性岩石的弹性行为由五个独立的常数决定。测量这些弹性常数的传统方法通常包括对三个相对于各向同性平面不同倾角的试样进行单轴压缩试验。然而，由于标本的异质性，这种方法可能会引入误差。在本研究中，推导了三组简单的反演公式，从静压过程中获得的应变数据中确定五个弹性常数，然后对单个倾斜试样施加轴向应力增量。这三组中的每一组都包括一个相同的剪切模量方程和一个不同的矩阵方程，用于其余四个弹性常数。虽然这些矩阵方程在外观上不同，但它们在数学上是等价的，并产生相同的解。为了便于坐标变换，采用Mehrabadi-Cowin表示法，将应变和应力状态表示为六维空间中的一阶张量，将柔度矩阵表示为同一空间中的二阶张量。所提出的反演公式的输入数据包括在与各向同性平面走向和倾斜方向对齐的坐标系中进行的应变测量。如果从应变数据可以推断出各向同性平面的方向，那么在任意坐标系下获得的应变测量值也可以作为输入。举例说明了所提出的方法的准确性和实际相关性。

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引用次数: 0

Timescales and solution regimes for heat driven thermo–poro–mechanical processes in geologic nuclear waste disposal 地质核废料处理中热驱动热孔力学过程的时间尺度和解决方案

IF 7.5 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2026-01-02 DOI: 10.1016/j.ijrmms.2025.106387

Bruce Gee , Mengsu Hu , Michael Manga

Deep geologic repositories are a proposed solution to dispose of nuclear waste at the end of its useful life. The radioactive decay of the contents inside the waste canisters releases heat into the repository near- and far-field environments that drives coupled heat transport, fluid transport, and stress development in the rock mass. The degree of coupling between processes and the corresponding temperature, pressure, and stress distributions can change significantly depending on the rock mass parameters. Not all coupled processes are simultaneously active and analysis time and effort can be reduced through a proper selection of relevant mechanisms. Here we use a combination of scaling analysis and numerical simulations to map the solutions across parameter space and establish dominant coupled processes regimes. We find that permeability has the greatest effect on the regimes. Pressure exhibits three regimes: an undrained regime at low permeability, transitioning to a drained regime, then a buoyant regime. Stress has two regimes: an undrained regime transitioning to a drained regime. Temperature has three regimes: conduction, advection, and buoyant convection. Conduction is dominant across most expected permeabilities, while the advection dominant regime only occurs at high permeability and is only expected in highly fractured rock masses. Analytical criteria to predict the transition from the drained to buoyant pressure regimes and the conductive to advective temperature regimes are derived and verified against the numerical simulations. The establishment of dominant process regimes allows for a reduction in computational time and complexity and enables more efficient analysis and design of nuclear waste repositories.

深层地质储存库是在其使用寿命结束时处理核废料的一种拟议解决方案。废罐内内容物的放射性衰变向储存库的近场和远场环境释放热量，从而驱动岩体中的耦合热传输、流体传输和应力发展。过程与相应的温度、压力和应力分布之间的耦合程度可以根据岩体参数发生显著变化。并非所有的耦合过程都是同时活动的，通过适当选择相关机制可以减少分析时间和工作量。在这里，我们使用标度分析和数值模拟相结合来映射跨参数空间的解决方案，并建立主导耦合过程制度。我们发现渗透率对状态的影响最大。压力表现出三种状态：低渗透率时的不排水状态，向排水状态过渡，然后是浮力状态。压力有两种状态：从不排水状态过渡到排水状态。温度有三种状态：传导、平流和浮力对流。在大多数预期渗透率中，传导占主导地位，而平流占主导地位只发生在高渗透率和高度断裂的岩体中。推导了预测从排水压力到浮力压力以及从导流温度到对流温度转变的分析准则，并通过数值模拟进行了验证。建立主导过程制度可以减少计算时间和复杂性，并能够更有效地分析和设计核废料储存库。

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引用次数: 0

Effects of confining stress on crack propagation and energy evolution during rock indentation: Insights from 2D-DEM simulations and implications for mechanized mining 岩石压痕过程中围应力对裂纹扩展和能量演化的影响：来自2D-DEM模拟的见解及其对机械化开采的影响

IF 7.5 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2026-01-01 DOI: 10.1016/j.ijrmms.2025.106392

Shaofeng Wang , Xinlei Shi , Yu Tang , Xin Cai , Zilong Zhou , Shanyong Wang

Non-explosive mechanized rock breaking technology is being increasingly adopted for deep rock excavation. The complexity of stress conditions in deep rock can significantly affect the efficiency of non-explosive mechanized rock breaking. However, the limited understanding of the rock breaking performance of conical picks under complex stress conditions constrains the application of this technique in deep rock engineering projects. In this study, the rock breaking characteristics associated with rock indentation under varying confining stress levels were investigated through numerical simulations using discrete element modelling software (MatDEM). The results indicate that tensile fractures predominantly occur during vertical indentation. As the confining stress increases, the length and quantity of radial cracks generated within the rock decrease. When the confining stress exceeds 9 MPa (16.6 % of the uniaxial compressive strength of rock), discrete distributions of tensile cracks form within the rock during the indentation process. Moreover, the evolution of rock energy exhibits a nonlinear double-peak trend with increasing confining stress, whereas the system heat evolution demonstrates a “decrease–increase–decrease” pattern. Additionally, the rock cuttability is evaluated by analysing the indentation force and specific energy during the initial leap process. The findings reveal that the rock is more easily fractured under low- or no-stress conditions. As the confining stress increases, the rock cuttability initially decreases but subsequently increases. This study reveals the nonlinear mechanism of confining stress on controlling crack propagation and energy evolution during rock indentation, providing a theoretical basis and technical pathway for non-explosive mechanized mining in deep hard rock.

非爆炸机械化破岩技术越来越多地应用于深部岩体开挖。深部岩体应力条件的复杂性对非爆炸破岩的效率有显著影响。然而，对复杂应力条件下锥形截齿破岩性能的认识有限，制约了该技术在深部岩石工程中的应用。在本研究中，采用离散元建模软件（MatDEM），通过数值模拟研究了不同围应力水平下与岩石压痕相关的岩石破碎特征。结果表明，拉伸断裂主要发生在垂直压痕阶段。随着围应力的增大，岩石内部产生的径向裂纹的长度和数量减小。当围应力超过9 MPa（占岩石单轴抗压强度的16.6%）时，压痕过程中岩石内部形成离散分布的拉伸裂纹。随着围应力的增大，岩石能量演化呈非线性双峰趋势，系统热演化呈“减小-增大-减小”模式。此外，通过分析初始跃迁过程中的压痕力和比能来评价岩石的可切削性。研究结果表明，岩石在低应力或无应力条件下更容易破裂。随着围应力的增大，岩石可切削性先减小后增大。研究揭示了岩石压痕过程中围应力控制裂纹扩展和能量演化的非线性机理，为深部硬岩非爆炸机械化开采提供了理论依据和技术途径。

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引用次数: 0

Fundamental insights into thermoporoelastic effects in thermal fracturing induced by cold fluid injection 低温流体注入致热压裂热孔弹性效应的基本见解

IF 7.5 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2025-12-31 DOI: 10.1016/j.ijrmms.2025.106393

Bin Chen , Qiaojie Shu , Quanlin Zhou , Yuan Wang , Hui Wu

Cold fluid injection in various subsurface applications may induce thermal fracturing, which is a coupled process of fracture propagation, heat conduction and convection, and fluid flow in the fractures and reservoir. While most existing studies employ a thermoelastic model, their accuracy may be compromised by thermoporoelastic effects. This study aims to systematically investigate the thermoporoelastic effects in thermal fracturing using numerical models of varying complexity. We first developed a fully coupled model incorporating all relevant physical processes including fracture propagation and arrest, heat and fluid transport in fractures and reservoir. A novel dimensionless framework with five key parameters is introduced to elucidate the thermo-hydro-mechanical coupling. Additionally, three partially coupled models are developed to isolate the effects of diffusion- and deformation-induced back stress, pore water contraction, and heat convection. Extensive numerical simulations indicate that (1) diffusion-induced back stress minimally impedes the fracture propagation in case of nonnegligible permeability and pressure differential, (2) deformation-induced back stress and pore water contraction primarily affect fracture growth in low-permeability rock, reducing and increasing fracture length by 3.81 %–18.61 % and 15.51 %–49.99 %, respectively, under undrained condition, (3) heat convection is the dominant thermoporoelastic effect under high permeability and pressure differential, significantly promoting fracture propagation, and (4) thermoporoelastic effects have negligible influence on thermal fracturing for permeability between 10⁻¹⁸ m² and 10⁻¹⁵ m².

在各种地下应用中，冷流体注入可诱发热压裂，热压裂是裂缝扩展、热传导和对流以及裂缝和储层中流体流动的耦合过程。虽然大多数现有研究采用热弹性模型，但其准确性可能受到热孔弹性效应的影响。本研究旨在利用不同复杂程度的数值模型系统地研究热压裂中的热孔弹性效应。首先，我们开发了一个完全耦合的模型，该模型包含了所有相关的物理过程，包括裂缝扩展和止裂、裂缝和储层中的热量和流体输送。引入了一个包含五个关键参数的新型无量纲框架来解释热-水-力耦合。此外，建立了三个部分耦合模型，以隔离扩散和变形引起的背应力、孔隙水收缩和热对流的影响。大量数值模拟表明：(1)在渗透率和压差不可忽略的情况下，扩散诱发的背应力对裂缝扩展的阻碍最小；(2)在不排水条件下，变形诱发的背应力和孔隙水收缩主要影响低渗透岩石的裂缝扩展，分别使裂缝长度减小3.81% ~ 18.61%和增大15.51% ~ 49.99%；(3)在高渗透率和压差条件下，热对流是热孔弹效应的主导作用，显著促进裂缝扩展；(4)渗透率在10 ~ 18 ~ 10 ~ 15 m2时，热孔弹效应对热压裂的影响可以忽略。

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引用次数: 0

Seismic response and energy release of simulated faults with varying morphology and pre-stress under impact disturbance 冲击扰动下不同形态和预应力模拟断层的地震响应和能量释放

IF 7.5 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2025-12-29 DOI: 10.1016/j.ijrmms.2025.106377

Dapeng Wang , Haojun Wang , Yaolan Tang , Haoyu Shi , Jianchun Li , Jian Zhao

Understanding the seismic response and energy release of fault surfaces under impact disturbances is crucial for predicting and assessing the risk of induced seismicity. This study utilized a biaxial Hopkinson bar system to conduct direct shear experiments on simulated faults with different interlocking segment characteristics, aiming to investigate the influence of fault surface morphology and pre-stress on seismic response and energy release. High-speed three-dimensional digital image correlation (3D-DIC) and rock CT were employed for qualitative and quantitative observations of dynamic deformation and failure characteristics. Experimental results indicate that fault surfaces with different morphological characteristics exhibited three types of seismic responses under varying initial normal stresses: climb, cut, and climb accompanied by fracture. The fracture consistently initiated at the teeth and subsequently propagated, exhibiting pronounced unilateral rupture characteristics. Under impact disturbance, both normal and shear strains exhibited a bell-shaped spatial distribution centered on the simulated fault surface, reflecting strong strain localization. This distribution was effectively characterized using a generalized Gaussian fitting framework, with the extracted shape parameters providing quantitative metrics for localized deformation behavior. The peak dynamic shear strength increased with both undulation angle and teeth number and positively correlated with initial normal stress. However, the friction coefficient did not show a strictly monotonic increasing trend. A fixed proportional relationship was observed between normal and shear strain during dynamic disturbance, varying based on loading conditions and fault surface characteristics. This relationship allows for a simplified calculation of the energy released from the simulated fault under dynamic disturbances. This research further clarifies the asperity-controlled seismic response and quantifies the strain-energy distribution induced by impact disturbances, offering valuable insights for assessing and monitoring induced seismic hazards under sudden dynamic loading.

了解断层面在冲击扰动下的地震反应和能量释放对于预测和评估诱发地震活动的风险至关重要。本研究利用双轴Hopkinson杆系对不同联锁段特征的模拟断层进行了直剪实验，旨在研究断层表面形态和预应力对地震反应和能量释放的影响。采用高速三维数字图像相关技术（3D-DIC）和岩石CT技术对岩石动态变形和破坏特征进行定性和定量观察。实验结果表明，不同形态特征的断层面在不同初始法向应力作用下表现出3种类型的地震响应：攀爬、切割和攀爬伴断裂。骨折始终在牙齿处开始并随后扩展，表现出明显的单侧断裂特征。在冲击扰动作用下，法向应变和剪切应变均以模拟断层表面为中心呈钟形空间分布，反映出较强的应变局部化。利用广义高斯拟合框架对该分布进行了有效表征，提取的形状参数为局部变形行为提供了定量度量。峰值动抗剪强度随波动角和齿数的增加而增加，且与初始法向应力呈正相关。但摩擦系数并没有表现出严格的单调增加趋势。在动态扰动过程中，法向应变和剪切应变之间存在固定的比例关系，且随加载条件和断层表面特征而变化。这种关系允许在动态扰动下简化模拟断层释放能量的计算。本研究进一步阐明了粗糙控制的地震反应，量化了冲击扰动引起的应变能分布，为突然动载诱发地震灾害的评估和监测提供了有价值的见解。

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引用次数: 0

Development of a procedure for predicting real-time seismic wave velocity in underground mines using discrete physical laboratory modelling and explainable artificial intelligence (XAI) 利用离散物理实验室模型和可解释人工智能（XAI）开发地下矿山实时地震波速度预测程序

IF 7.5 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2025-12-29 DOI: 10.1016/j.ijrmms.2025.106391

Hanan Samadi, Fidelis Suorineni

Seismic event source locations in underground mines are crucial for safety, production efficiency, and mine profitability. Common microseismic monitoring systems rely on a constant input velocity model and periodic updating for seismic event source locations calculation. This approach often results in significant errors because of the constantly changing underground mine conditions from mining activities, discrete geological features, intersection of different rock lithologies, and the complex underground mine infrastructure, such as a changing network of excavations and the use of backfill. To address this problem, this study used discrete physical models mimicking snapshots in time to track the velocity changes of the constantly changing underground mining environment due to mining activities. The data generated in the laboratory is then analyzed using machine learning to develop a method for predicting input velocity in real-time that reflects the ground condition at any time, for use in the seismic event source determination algorithm, particularly SIMPLEX. The discrete physical models used to mimic the constantly changing underground mine conditions were concrete blocks (synthetic rocks) and granite in the form of cubes of diverse sizes and physical conditions. The SAEU3H Acoustic Emission system was used to generate and track the acoustic signals in various known locations around the blocks in their different physical conditions. One sensor served as the event source (pulse generator), while others served as receivers. Given the data generated from various mimicked ground conditions, smart computational techniques, including explainable artificial intelligence (XAI), were applied to predict wave velocity accurately for given ground conditions. The developed models showed a strong correlation between predicted and actual wave velocity values, particularly with the stacking-ensemble algorithm that gave the best performance (R² = 0.97, NRMSE = 0.002, MAPE = 0.0001). The findings of the study have the potential to be implemented in seismic monitoring systems for real-time velocity prediction in underground mines to improve seismic event source location accuracy.

地下矿山地震事件源定位对矿山安全、生产效率和效益至关重要。常用的微震监测系统依赖于恒定输入速度模型和周期性更新的地震事件源位置计算。由于采矿活动导致地下矿山条件不断变化，地质特征离散，不同岩石岩性相交，以及复杂的地下矿山基础设施（如不断变化的挖掘网络和回填体的使用），这种方法往往会导致重大误差。为了解决这一问题，本研究采用离散物理模型模拟实时快照，跟踪由于采矿活动而不断变化的地下采矿环境的速度变化。然后使用机器学习对实验室生成的数据进行分析，以开发一种实时预测输入速度的方法，该方法可以随时反映地面状况，用于地震事件源确定算法，特别是SIMPLEX。用于模拟不断变化的地下矿山条件的离散物理模型是混凝土块（合成岩石）和花岗岩，它们以不同尺寸和物理条件的立方体形式存在。利用SAEU3H声发射系统在不同物理条件下生成并跟踪区块周围不同已知位置的声信号。一个传感器作为事件源（脉冲发生器），而其他传感器作为接收器。考虑到各种模拟地面条件产生的数据，应用智能计算技术，包括可解释人工智能（XAI），来准确预测给定地面条件下的波速。所建立的模型显示，预测波速值与实际波速值之间存在很强的相关性，特别是叠加-集成算法的表现最佳（R2 = 0.97, NRMSE = 0.002, MAPE = 0.0001）。研究结果有可能应用于地下矿山地震监测系统中进行实时速度预测，以提高地震事件源定位精度。

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引用次数: 0

Structure-constrained semi-supervised segmentation of complex geomaterial CT images 复杂几何材料CT图像的结构约束半监督分割

IF 7.5 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2025-12-29 DOI: 10.1016/j.ijrmms.2025.106395

Yifan Tang , Jianfeng Liu , Jinbing Wei , Honghao Yuan , Danli Li , Wentao Feng

Accurate segmentation of pore–fracture systems in rock CT images remains a fundamental challenge due to the scarcity of annotated data and the morphological complexity of heterogeneous geological materials. This study presents a semi-supervised segmentation framework that integrates limited manual annotations, pseudo-labels generated by the Segment Anything Model (SAM), and a multi-task learning strategy guided by physical structure constraints. A 2D nnU-Net-like encoder–decoder backbone, identified as the most effective among the evaluated architectures, is further enhanced with a deterministically weighted multi-task loss that combines a primary segmentation loss with structure-aware regularization terms enforcing consistency in areal porosity, fractal dimension, and void count. The experimental dataset comprises high-resolution CT slices of glacial till and failed salt rock. Training is conducted on 300 manually annotated small slices, 200 augmented small slices, and 100 SAM-based pseudo-labeled large slices, while evaluation is performed on 20 fully annotated large CT slices from specimens not used for training data extraction. The proposed model achieves a mean mIoU of 91.65 % and mean F1-score of 92 %, substantially outperforming standard baselines. Structural metrics indicate strong fidelity, with a mean areal porosity error of 0.43 % and a mean void count error of 42.5. Ablation studies validate the effectiveness of weak supervision and structure-aware constraints in enhancing robustness, particularly in geologically complex regions. A complementary parameter sensitivity analysis further shows that the structure-aware loss weights strongly influence structural descriptors, whereas the model remains relatively robust to variations in conventional hyperparameters. Overall, this framework demonstrates the feasibility of high-accuracy segmentation under sparse supervision and provides a transferable solution for geotechnical imaging and data-driven rock characterization. Its extensibility to various lithologies and high-resolution CT datasets supports future applications in subsurface modeling and geomechanical analysis.

由于注释数据的稀缺性和非均质地质材料的形态复杂性，岩石CT图像中孔隙-破裂系统的准确分割仍然是一个根本性的挑战。本研究提出了一种半监督分词框架，该框架集成了有限的人工注释、由分段任意模型（SAM）生成的伪标签以及由物理结构约束引导的多任务学习策略。2D nnu - net类编码器-解码器骨干被认为是评估体系结构中最有效的，通过确定性加权多任务损失进一步增强，该损失结合了主要分割损失和结构感知正则化项，从而增强了面积孔隙度、分形维数和孔隙计数的一致性。实验数据集包括高分辨率的冰碛物和破碎盐岩CT切片。对300个人工标注的小切片、200个增强小切片和100个基于sam的伪标注大切片进行训练，对20个未用于训练数据提取的标本进行完全标注的大CT切片进行评估。该模型的平均mIoU为91.65%，平均f1得分为92%，大大优于标准基线。结构指标具有较强的保真度，平均面孔隙率误差为0.43%，平均孔隙计数误差为42.5。消融研究证实了弱监督和结构感知约束在增强鲁棒性方面的有效性，特别是在地质复杂地区。补充参数敏感性分析进一步表明，结构感知损失权重强烈影响结构描述符，而该模型对常规超参数的变化仍然相对稳健。总体而言，该框架证明了稀疏监督下高精度分割的可行性，并为岩土成像和数据驱动的岩石表征提供了可转移的解决方案。它可扩展到各种岩性和高分辨率CT数据集，支持未来在地下建模和地质力学分析中的应用。

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引用次数: 0

Rationality analysis of lattice Boltzmann method simulation for gas seepage in mesoscale porous media 点阵玻尔兹曼法模拟中尺度多孔介质中气体渗流的合理性分析

IF 7.5 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2025-12-29 DOI: 10.1016/j.ijrmms.2025.106382

Wei Wang , Weizhong Chen , Jianping Yang , Haizeng Pan , Jiawei Huang , Feilong Liu , Ziang Xia

The rationality of applying the lattice Boltzmann Method (LBM) to the study of gas permeation in porous media, particularly in rocks, requires further discussion. This article focuses on the study of micro-nano scale pores typical of rock structures. It explores the applicability of algorithms for mesoscale gas seepage in porous media, including collision stream, boundary condition, and relaxation time related to the Knudsen number, from the LBM principle. This research firstly verifies classic problems such as Couette flow, Poiseuille flow, around circular cylinder flow, and variable cross-section slit flow. Then, the seepage behaviours of various gases are simulated under different channel sizes. The improved quartet structure generation set (QSGS) method is employed to generate porous media grids for testing. Finally, the calculations for real microfluidic chip channels are performed and compared with experimental phenomena. Results indicate that the LBM algorithm used in this article can accurately simulate the shear collision behaviour between fluid particles as well as their interactions with obstacles. Using the relaxation time associated with the Knudsen number and the rebound-slip combination boundary can effectively replicate gas slip effects under micro-nano scales and demonstrate the differences in gas permeation behaviour of different types in LBM simulation. Additionally, LBM can also effectively reflect the influence of micro-nano scale porosity, directionality, and tortuosity on gas permeability. This research supports the credibility of LBM for simulating gas seepage in mesoscale porous media.

晶格玻尔兹曼方法（LBM）应用于多孔介质特别是岩石中气体渗透研究的合理性有待进一步探讨。本文主要研究岩石结构中典型的微纳尺度孔隙。从LBM原理出发，探讨了多孔介质中尺度气体渗流算法的适用性，包括碰撞流、边界条件和与Knudsen数相关的松弛时间。本研究首先验证了Couette流动、Poiseuille流动、绕圆柱流动、变截面狭缝流动等经典问题。然后，模拟了不同通道尺寸下各种气体的渗流行为。采用改进的四重结构生成集（QSGS）方法生成多孔介质网格进行测试。最后，对实际微流控芯片的通道进行了计算，并与实验现象进行了比较。结果表明，本文所采用的LBM算法可以准确地模拟流体颗粒之间的剪切碰撞行为以及它们与障碍物的相互作用。利用与Knudsen数相关的松弛时间和回弹-滑移组合边界可以有效地模拟微纳尺度下的气体滑移效应，并展示不同类型气体在LBM模拟中的渗透行为差异。此外，LBM还能有效反映微纳尺度孔隙度、方向性和弯曲度对渗透率的影响。本研究支持了LBM模拟中尺度多孔介质中气体渗流的可信性。

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引用次数: 0