International Journal of Rock Mechanics and Mining Sciences最新文献_第2页

Identification of fluid-entry clusters and diagnosis of downhole events based on high-frequency water hammer pressure 基于高频水锤压力的流体进入簇识别与井下事件诊断

IF 7.5 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2026-04-01 Epub Date: 2026-02-02 DOI: 10.1016/j.ijrmms.2026.106437

Shuangshuang Sun , Yongming He , Lijun Liu , Yanchao Li , Longqing Zou , Liang Yang

Accurate identification of fluid-entry clusters during hydraulic fracturing, and fine-scale diagnosis of downhole fracturing events, are crucial for optimizing fracturing design and enhancing reservoir stimulation performance. However, existing water hammer pressure-based monitoring methods for fracturing are mostly limited to identifying the dominant fluid-entry cluster within a stage and struggle to provide a fine-scale diagnosis of downhole fracturing events. This study establishes a fracturing monitoring method based on high-frequency water hammer pressure. By performing time-domain and frequency-domain analysis on the high-frequency water hammer signal and employing a composite filtering method, the signal quality was significantly enhanced. Furthermore, this study achieved the identification of multiple fluid-entry clusters within a stage and the fine-scale diagnosis of downhole fracturing events through cepstrum analysis and time-depth conversion, as well as the effective characterization of the dynamic distribution of fracturing fluid under different conditions. Verification with simulated data confirms that the identification results are consistent with the simulation settings, thus validating the reliability of the method. Field application has enabled the fine-scale diagnosis of downhole fracturing events such as diverter effectiveness, plug leakage, and plug slippage, and further analyzed the cepstral response characteristics and treating pressure curve characteristics associated with different events. The proposed method provides an effective tool for diagnosing fracturing conditions during field operations, thereby offering valuable insights for optimizing fracturing design and enhancing reservoir stimulation effectiveness.

水力压裂过程中流体进入簇的准确识别和井下压裂事件的精细诊断，对于优化压裂设计和提高储层增产效果至关重要。然而，现有的基于水锤压力的压裂监测方法大多局限于识别一个压裂段内的主要流体进入簇，难以提供井下压裂事件的精细诊断。本研究建立了一种基于高频水锤压力的压裂监测方法。通过对高频水锤信号进行时域和频域分析，并采用复合滤波方法，显著提高了信号质量。通过倒谱分析和时间-深度转换，实现了同一段内多个流体进入簇的识别和井下压裂事件的精细诊断，有效表征了压裂液在不同条件下的动态分布。仿真数据验证，识别结果与仿真设置一致，验证了方法的可靠性。通过现场应用，可以对暂堵剂有效性、桥塞泄漏和桥塞滑移等井下压裂事件进行精细诊断，并进一步分析不同事件相关的倒谱响应特征和处理压力曲线特征。该方法为现场作业中的压裂状况诊断提供了有效工具，从而为优化压裂设计和提高储层增产效果提供了有价值的见解。

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引用次数: 0

Effect of fracture shear dilation on flow anisotropy for variable normal stress and fracture size 变法向应力和变裂缝尺寸时裂缝剪切扩张对流动各向异性的影响

IF 7.5 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2026-04-01 Epub Date: 2026-02-04 DOI: 10.1016/j.ijrmms.2026.106428

Jinkyo Lee , Ki-Bok Min , Liangchao Zou , Vladimir Cvetkovic

Fracture shear can induce flow channeling within the fracture plane, enhancing flow perpendicular to the fracture shear direction. The resulting flow anisotropy is crucial for determining optimal well locations at geothermal sites, where efficient heat extraction relies on productive fluid circulation. This research examines the impact of shear on flow anisotropy under variable conditions of normal stress, shear displacement, and fracture size. The research comprises three main stages: (1) simulating fracture shear incorporating asperity degradation, (2) modeling preferential fluid flow within a sheared fracture, and (3) upscaling the laboratory-scale results to the reservoir scale of a hundred-meter. Two fracture surfaces with dimensions of 10

\times

10 cm and one fracture surface with a dimension of 1

\times

1m are used for analysis. A numerical shear model based on elastic-plastic contact mechanics is employed to simulate asperity degradation during shear. Flow simulation on a sheared surface reveal significantly increased permeability anisotropy ratio defined as the ratio of permeability perpendicular to parallel to the shear direction. This permeability anisotropy ratio still prevailed and even increased with higher normal stress, emphasizing the importance of considering flow anisotropy under high-stress conditions. The effect of fracture sizes is investigated using square fractures with side length from 10 cm to 60 cm, extracted from the 1

\times

1m fracture. While increasing fracture size led to higher permeability and reduced variation in flow anisotropy across the fractures, anisotropy remained evident and significant. To investigate the effect of anisotropy in reservoir scale, a hundred-meter scale reservoir model with an upscaled sheared fracture was constructed. Injection tests showed that higher flow rates were observed when injection and production wells were positioned perpendicular to shear. The results demonstrate that perpendicular flow is enhanced both at the laboratory and reservoir scale, highlighting the importance of considering the influence of fracture shear on flow anisotropy for optimizing well locations.

裂缝剪切可以诱导裂缝面内的窜流，增强垂直于裂缝剪切方向的流动。由此产生的流体各向异性对于确定地热站点的最佳井位至关重要，在地热站点中，有效的热量提取依赖于生产流体循环。本研究考察了在不同的正应力、剪切位移和裂缝尺寸条件下，剪切对流动各向异性的影响。该研究包括三个主要阶段：(1)模拟含粗糙度降解的裂缝剪切；(2)模拟剪切裂缝内的优先流体流动；(3)将实验室规模的结果扩大到百米的油藏规模。分析采用两个尺寸为10 × 10 cm的断裂面和一个尺寸为1× 1m的断裂面。采用基于弹塑性接触力学的数值剪切模型来模拟剪切过程中的粗糙度退化。剪切表面上的流动模拟表明，渗透率各向异性比（垂直于剪切方向的渗透率与平行于剪切方向的渗透率之比）显著增加。这种渗透率各向异性比在较高的法向应力条件下仍然存在，甚至有所增加，强调了在高应力条件下考虑流动各向异性的重要性。采用边长为10 ~ 60 cm的方形裂缝，从1× 1m的裂缝中提取裂缝尺寸的影响。虽然增大裂缝尺寸会提高渗透率，降低裂缝间流动各向异性的变化，但各向异性仍然明显而显著。为了研究各向异性对储层尺度的影响，建立了百米尺度剪切裂缝模型。注入测试表明，当注入井和生产井垂直于剪切方向时，可以观察到更高的流量。结果表明，在实验室和油藏尺度上，垂直流动都得到了增强，这突出了考虑裂缝剪切对流动各向异性的影响对优化井位的重要性。

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引用次数: 0

Structural barriers to complete homogenization and wormholing in dissolving porous and fractured rocks 溶蚀性多孔和裂隙岩石中完全均质化和虫孔形成的结构障碍

IF 7.5 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2026-04-01 Epub Date: 2026-01-31 DOI: 10.1016/j.ijrmms.2026.106431

Tomasz Szawełło , Jeffrey D. Hyman , Peter K. Kang , Piotr Szymczak

Dissolution in porous media and fractured rocks alters both the chemical composition of the fluid and the physical properties of the solid. Depending on system conditions, reactive flow may enlarge pores uniformly, widen pre-existing channels, or trigger instabilities that form wormholes. The resulting pattern reflects feedbacks among advection, diffusion, surface reaction, and the initial heterogeneity of the medium. Porous and fractured media can exhibit distinct characteristics — for example, the presence of large fractures can significantly alter the network topology and overall connectivity of the system. We quantify these differences with three network models — a regular pore network, a disordered pore network, and a discrete fracture network — evaluated with a unified metric: the flow focusing profile. This metric effectively captures evolution of flow paths across all systems: it reveals a focusing front that propagates from the inlet in the wormholing regime, a system-wide decrease in focusing during uniform dissolution, and the progressive enlargement of pre-existing flow paths in the channeling regime. The metric shows that uniform dissolution cannot eliminate heterogeneity resulting from the network topology. This structural heterogeneity — rather than just pore-diameter or fracture-aperture variance — sets a fundamental limit on flow homogenization and must be accounted for when upscaling dissolution kinetics from pore or fracture scale to the reservoir level.

在多孔介质和裂隙岩石中的溶解会改变流体的化学成分和固体的物理性质。根据系统条件的不同，反应性流动可能会均匀地扩大孔隙，扩大已有的通道，或者引发不稳定，形成虫孔。所得到的模式反映了平流、扩散、表面反应和介质初始非均质性之间的反馈。多孔介质和裂缝介质可以表现出不同的特征，例如，大裂缝的存在可以显著改变网络拓扑结构和系统的整体连通性。我们通过三种网络模型（规则孔隙网络、无序孔隙网络和离散裂缝网络）来量化这些差异，并使用统一的度量标准进行评估：流动聚焦剖面。该指标有效地捕捉了所有体系中流动路径的演变：它揭示了在虫洞状态下从入口传播的聚焦前沿，在均匀溶解过程中整个系统的聚焦减少，以及在窜流状态下原有流动路径的逐渐扩大。该度量表明，均匀溶解不能消除网络拓扑结构造成的异质性。这种结构非均质性（而不仅仅是孔径或裂缝孔径差异）限制了流体均质性，当将溶蚀动力学从孔隙或裂缝尺度提升到油藏水平时，必须考虑到这种非均质性。

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引用次数: 0

Study on non-convexity for Zhang-Zhu strength criterion based on microfracture mechanics 基于微断裂力学的张-朱强度准则非凸性研究

IF 7.5 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2026-04-01 Epub Date: 2026-02-06 DOI: 10.1016/j.ijrmms.2026.106452

Qi Zhang , Yixin Shen , Hehua Zhu , Xiaojun Wang , Yuechao Pei

The Zhang-Zhu (ZZ) strength criterion, as a three-dimensional Hoek-Brown strength criterion, accurately characterizes the deep rock failure under the true triaxial stress condition (σ₁>σ₂>σ₃). However, its failure envelope in the deviatoric plane shows non-smoothness and non-convexity, with the underlying physical mechanism for the non-convexity requiring further exploration. This study derives a micro-Zhang-Zhu (micro-ZZ) strength criterion from the microfracture mechanics, following the formulation of the ZZ strength criterion. The validation against the true triaxial test reveals that 87.2% of the data points fall within a ±5% relative error, indicating that fracture behavior from microcrack clusters is strongly consistent with true triaxial test results. The micro-ZZ strength criterion shows a maximum mean absolute percentage error (MAPE) of only 2.39% relative to the ZZ strength criterion, confirming its high consistency with the ZZ strength criterion. Therefore, a correlation between microfracture mechanisms and macroscopic non-convexity of the Zhang-Zhu strength criterion is established based on the micro-ZZ strength criterion. The failure envelopes of both strength criteria closely match, exhibiting strong agreement in their intersection angles θ_d. The effect of the microcrack density on the non-convexity is further explored to reveal the underlying physical mechanism of non-convexity. The results indicate that the non-convexity increases with the microcrack density and approaches 90° as the density tends to zero, indicating the microcrack is one of the micromechanical mechanisms contributing to the non-convexity. Finally, the effects of parameters on the non-convexity and the sensitivity of these parameters are discussed. Five stress state and material parameters influence the non-convexity, with the friction coefficient μ and the compression-extension stress ratio σ_c/σ_t identified as the dominant parameters, with the strongest interaction between them.

Zhang-Zhu （ZZ）强度准则作为一种三维Hoek-Brown强度准则，准确表征了真三轴应力（σ1>σ2>σ3）条件下深部岩石的破坏特征。但其在偏平面上的破坏包络呈现非光滑性和非凸性，其非凸性的物理机制有待进一步探讨。本文从微断裂力学角度出发，推导出微张-柱强度准则，并在此基础上建立了微ZZ强度准则。对真三轴试验的验证表明，87.2%的数据点的相对误差在±5%以内，表明微裂纹簇的断裂行为与真三轴试验结果高度一致。微-ZZ强度准则相对于ZZ强度准则的最大平均绝对百分比误差（MAPE）仅为2.39%，与ZZ强度准则具有较高的一致性。因此，基于微zz强度准则，建立了张柱强度准则微观断裂机制与宏观非凸性之间的关联。两种强度准则的破坏包络紧密匹配，在相交角θd处表现出很强的一致性。进一步探讨了微裂纹密度对非凸性的影响，揭示了微裂纹非凸性的物理机制。结果表明：微裂纹的非凸度随微裂纹密度的增大而增大，当微裂纹密度趋于零时，非凸度趋于90°，表明微裂纹是导致非凸度的微力学机制之一；最后讨论了参数对非凸性和灵敏度的影响。5种应力状态和材料参数对非凸性有影响，其中摩擦系数μ和压伸应力比σc/σt是主导参数，相互作用最强。

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引用次数: 0

Hydraulic convergence-confinement method 水力收敛约束法

IF 7.5 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2026-04-01 Epub Date: 2026-02-05 DOI: 10.1016/j.ijrmms.2026.106439

J.H. Jeong , Y.J. Shin , S.H. Kim , J.H. Shin

Groundwater control is a primary concern during tunnel excavation, and addressing groundwater issues has remained one of the key challenges in tunnel engineering. While extensive research has been conducted on the mechanical behaviour hydraulic considerations in tunnel design have largely been limited to evaluating groundwater inflow rates and water pressure acting on the lining. This research investigates hydraulic equilibrium process and drainage control mechanisms associated with tunnelling. Through theoretical analysis, the hydraulic response of the ground and tunnel lining were examined assuming laminar flow through a homogeneous and stiff rock mass, leading to the development of the hydraulic convergence-confinement concept (HCC). This proposed concept was validated through numerical simulations and small-scale model tests. The results show that the HCC is analogous to the mechanical convergence-confinement concept which elucidates the mechanical principles of tunnel formation, and it is identified as an effective tool for explaining hydraulic behaviour caused by tunnelling. The introduction of the HCC provides a hydraulic control framework for interpreting hydraulic equilibrium during tunnel excavation. It also offers a conceptual basis for hydraulic tunnel design, enabling the establishment of arbitrary design hydraulic boundary conditions. Furthermore, the HCC offers a logical foundation for the limited-drainage tunnel concept, which aims to restrict tunnel inflow and/or control the groundwater-table drawdown.

地下水控制是隧道开挖的首要问题，解决地下水问题一直是隧道工程的关键挑战之一。虽然对隧道的力学性能进行了广泛的研究，但在隧道设计中考虑的水力因素在很大程度上仅限于评估地下水流入速率和作用在衬砌上的水压。研究了隧道掘进过程中的水力平衡过程和排水控制机制。通过理论分析，研究了在均匀坚硬岩体层流条件下的地面和隧道衬砌的水力响应，从而提出了水力收敛约束概念（HCC）。通过数值模拟和小规模模型试验验证了这一概念。结果表明，HCC类似于力学收敛约束概念，阐明了隧道形成的力学原理，并被认为是解释隧道开挖引起的水力行为的有效工具。HCC的引入为解释隧道开挖过程中的水力平衡提供了一个水力控制框架。为水工隧洞设计提供了概念依据，实现了任意设计水工边界条件的建立。此外，HCC为有限排水隧道概念提供了逻辑基础，该概念旨在限制隧道流入和/或控制地下水位下降。

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引用次数: 0

Experimental insights into CO2 flow in fractured crystalline rock 裂隙结晶岩中CO2流动的实验研究

IF 7.5 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2026-04-01 Epub Date: 2026-02-05 DOI: 10.1016/j.ijrmms.2026.106443

Nikita Bondarenko , Hyunbin Kim , Kiseok Kim , Roman Y. Makhnenko

The injection of carbon dioxide (CO₂) or the non-wetting fluid intrusion into crystalline rock remains being a poorly understood process due to the complexities in characterizing very low permeable and stiff geomaterials. This knowledge gap is critical for enhanced geothermal systems and in-situ carbon mineralization projects where CO₂ may serve as a mobile fluid within fractured crystalline formations. Most of the existing studies rely on numerical simulations with limited experimental validations and do not fully consider the complexity of multi-phase flow. Hereby, we adopt a novel method to evaluate the degree of saturation of the non-wetting fluid in a tight rock with nanometer scale pore sizes from accurate poromechanical and hydraulic measurements, as well as wetting and non-wetting fluid characteristics. We select thermally damaged granite and naturally fractured rhyolite as representative crystalline rock, fully saturate them with water, and perform simultaneous injection of water and liquid CO₂. The flow properties are measured using the core flooding device that allows observation of multiple fluid flow at controlled rates. CO₂ breakthrough pressures for pressurized fractured crystalline rock are measured to be on the order of 0.1–1 MPa. The exponent values for relative water permeabilities are 1.6 for granite and 1.9 for rhyolite – significantly lower than those typically reported for tight rock, meaning that the fluid flow is mainly governed by the fractures. The exponent values for relative CO₂ permeability are above 5.5, indicating high sensitivity to the degree of CO₂ saturation. Moreover, CO₂ saturation appears to remain below 50%, even when CO₂ is the only injected fluid and its overpressures exceeds 6 MPa. Overall, this study highlights significant limitations in using CO₂ as a working fluid for geoenergy projects in crystalline rock.

由于表征极低渗透性和刚性岩土材料的复杂性，对注入二氧化碳（CO2）或非润湿流体侵入结晶岩石的过程仍然知之甚少。这种知识差距对于强化地热系统和原位碳矿化项目至关重要，在这些项目中，二氧化碳可能作为断裂晶体地层中的流动流体。现有的研究大多依赖于数值模拟，实验验证有限，没有充分考虑多相流的复杂性。为此，我们采用了一种新颖的方法，通过精确的孔隙力学和水力测量，以及润湿和非润湿流体特性，来评价纳米尺度致密岩石中非润湿流体的饱和度。选取热损伤花岗岩和自然断裂流纹岩作为典型结晶岩，充分饱和水，同时注入水和液态CO2。流动特性是使用岩心驱油装置来测量的，该装置可以在控制速率下观察多种流体的流动。经测量，受压破碎结晶岩的CO2突破压力约为0.1-1 MPa。花岗岩的相对渗透率指数为1.6，流纹岩的相对渗透率指数为1.9，明显低于通常报道的致密岩石的相对渗透率指数，这意味着流体流动主要受裂缝控制。CO2相对渗透率指数值均在5.5以上，表明对CO2饱和度的敏感性较高。此外，即使只有二氧化碳注入流体，且其超压超过6 MPa， CO2饱和度似乎仍低于50%。总的来说，这项研究强调了在结晶岩石中使用二氧化碳作为地能项目的工作流体的重大局限性。

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引用次数: 0

An intelligent recognition and classification method for TBM tunnel surrounding rock based on cross-attention transformer and multi-source data fusion 基于交叉关注变压器和多源数据融合的TBM隧道围岩智能识别分类方法

IF 7.5 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2026-04-01 Epub Date: 2026-02-09 DOI: 10.1016/j.ijrmms.2026.106438

Chen Xu , Chao Wang , Mingchao Li , Xiaoli Liu

Accurate classification of surrounding rock is vital for ensuring the safety and efficiency of TBM operations. To address the limitations of existing methods, which often overlook ascending-stage dynamics, encounter difficulties in multi-source data fusion, and lack interpretability, this study proposes a Cross-Attention Transformer with XGBoost (CA-Trans-XGBoost). The study uses Section IV of the Yinsong Water Diversion Project as a case study, collecting and organizing 802 days of operational data and cutter replacement records. A Transformer encoder was applied to extract dynamic features from the ascending stage, while an MLP modeled structured features from the stable stage. A cross-attention mechanism was introduced to enhance feature interaction, and fused features were further processed with XGBoost for classification and feature importance analysis. Results show that CA-Trans-XGBoost achieves the best performance among six models, with an Accuracy, Precision, Recall, and Macro-F1 of 95.0 %, 93.6 %, 92.6 %, and 92.9 %, respectively. The model shows clear advantages in identifying minority classes II and V. Further analysis confirms that a 30-s ascending stage is the optimal temporal window. The proposed method balances predictive accuracy and interpretability, providing support for intelligent TBM excavation and parameter optimization.

准确的围岩分类是保证隧道掘进机安全高效运行的关键。为了解决现有方法的局限性，即往往忽略上升级动力学，在多源数据融合中遇到困难，以及缺乏可解释性，本研究提出了一种具有XGBoost的交叉注意转换器（CA-Trans-XGBoost）。本研究以银松引水工程四段为例，收集整理了802天的运行数据和刀具更换记录。采用变压器编码器提取上升阶段的动态特征，采用MLP对稳定阶段的结构化特征进行建模。引入交叉注意机制增强特征交互，并利用XGBoost对融合后的特征进行分类和特征重要性分析。结果表明，CA-Trans-XGBoost在6个模型中表现最佳，准确率为95.0%，Precision为93.6%，Recall为92.6%，Macro-F1为92.9%。该模型在识别少数民族II类和少数民族v类方面具有明显的优势。进一步分析证实，30-s的上升阶段是最优的时间窗口。该方法平衡了预测精度和可解释性，为TBM智能开挖和参数优化提供了支持。

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引用次数: 0

Low-stress creep behavior of multiple salt caverns under cyclic operations 循环作用下多盐洞室的低应力蠕变行为

IF 7.2 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2026-03-23 DOI: 10.1016/j.ijrmms.2026.106514

Kyung Won Chang, Tonya S.A. Ross

引用次数: 0

Triaxial cutting force prediction model for disc cutters based on full-scale rotary cutting tests of composite rock strata 基于复合岩层全尺寸旋转切削试验的圆盘刀具三轴切削力预测模型

IF 7.2 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

International Journal of Rock Mechanics and Mining Sciences

Pub Date : 2026-03-23 DOI: 10.1016/j.ijrmms.2026.106517

Ting Ren, Jin Yu, Longchuan Deng, Chi Zhang, Seisuke Okubo