Geomechanics for Energy and the Environment最新文献_第8页

Coupled SPH–FEM modeling of waterjet-assisted coal cutting: Numerical simulation and experimental validation 水射流辅助采煤SPH-FEM耦合建模：数值模拟与实验验证

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-08-20 DOI: 10.1016/j.gete.2025.100732

Satar Mahdevari , Pedram Bakhtiari Haftlang

Coal remains a cornerstone of global energy supply, driving the need for more efficient and technologically advanced extraction methods. This study introduces a numerical framework that couples the Smoothed Particle Hydrodynamics (SPH) with the Finite Element Method (FEM) to model the dynamic response of coal under waterjet-assisted cutting—an emerging technique recognized for its applicability, minimal stress disturbance, and safe working conditions in underground mining. Implemented in LS-DYNA, the model captures two-phase fluid–solid interactions, including jet-induced fracture initiation, propagation, and material removal. A detailed parametric investigation evaluates the effects of jet velocity, nozzle diameter, impingement angle, and cutting duration on coal fragmentation behavior. Model predictions were rigorously validated through controlled laboratory experiments, achieving reliable correlation with empirical results—showing mean absolute errors of 7.2 % in Cutting Depth (CD) and 5.8 % in Cutting Volume (CV). To address the performance constraints of Pure Water Jet (PWJ) systems, extended simulations were conducted for Abrasive Water Jet (AWJ) and Ice Abrasive Water Jet (IAWJ) techniques. The AWJ configuration enhanced CD and CV by 51 % and 66 %, respectively, while IAWJ achieved up to 20 % improvement over PWJ. Stress field analysis further revealed that increased jet velocity is significantly more effective than nozzle enlargement in maximizing cutting efficiency. These findings not only validate the SPH–FEM model as a predictive tool but also offer actionable insights for optimizing next-generation waterjet systems in deep coal mining applications.

煤炭仍然是全球能源供应的基石，推动了对更高效、技术更先进的开采方法的需求。本文介绍了一种数值框架，将光滑颗粒流体动力学（SPH）与有限元法（FEM）相结合，来模拟煤在水射流辅助切割下的动态响应。水射流辅助切割是一种新兴的技术，因其适用性、应力扰动最小和在地下开采中安全的工作条件而得到认可。该模型在LS-DYNA中实现，可捕获两相流固相互作用，包括射流诱导的裂缝萌生、扩展和材料去除。详细的参数研究评估了射流速度、喷嘴直径、撞击角和切割时间对煤破碎行为的影响。模型预测通过受控的实验室实验得到了严格验证，与经验结果实现了可靠的相关性——切割深度（CD）的平均绝对误差为7.2 %，切割体积（CV）的平均绝对误差为5.8 %。为了解决纯水射流（PWJ）系统的性能限制，对磨料水射流（AWJ）和冰磨料水射流（IAWJ）技术进行了扩展模拟。AWJ配置使CD和CV分别提高了51 %和66 %，而IAWJ比PWJ提高了20 %。应力场分析进一步表明，增大射流速度比增大喷嘴更能有效地提高切削效率。这些发现不仅验证了SPH-FEM模型作为预测工具的有效性，而且为优化深煤开采应用中的下一代水射流系统提供了可行的见解。

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引用次数: 0

Damage and acoustic characteristics of water-saturated coals with different ranks under liquid nitrogen freezing and thawing treatments 不同等级水饱和煤在液氮冻融作用下的损伤及声学特性

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-08-05 DOI: 10.1016/j.gete.2025.100730

Lei Qin , Jiawei Li , Haifei Lin , Shugang Li , Miao Mu , Shiyin Lv , Niandong Chen

Geological variability results in coal seams with diverse ranks exhibiting distinct physical properties, critically influencing liquid nitrogen (LN₂) fracturing outcomes. We systematically assess the mechanical and acoustic damage induced by single LN₂ freeze-thaw (LNSFT) and repeated freeze-thaw cycles (LNCFT) in three representative coal ranks—lignite, bituminite, and anthracite—via ultrasonic measurement, uniaxial compression, and acoustic emission (AE) techniques. Results demonstrate that initially, pore water solidification enhances coal strength and acoustic integrity; subsequently, crack initiation and propagation induced by frost heave, thermal stress, and LN₂ expansion progressively weaken these properties. This balance between strengthening and weakening is primarily governed by coal pore structure, fissures, and moisture content. AE patterns under loading distinctly follow steady-state, activation, and attenuation phases, with both the freezing and thawing phases promoting shear-oriented fracture development. Damage indices (D), computed from ultrasonic P-wave velocity (v), peak strength (σ), and elastic modulus (E), reveal an inverse correlation between freeze-thaw damage severity and coal rank, indicating that higher-rank coals exhibit greater structural stability and freeze-thaw resistance. Furthermore, under equivalent cumulative freezing durations, LNCFT cause significantly greater damage than LNSFT, highlighting a cumulative damage effect. These insights provide critical guidance for optimizing LN₂ fracturing techniques aimed at enhancing coal seam permeability.

地质变异性导致不同等级的煤层具有不同的物理性质，严重影响液氮（LN 2）压裂效果。通过超声测量、单轴压缩和声发射（AE）技术，系统地评估了褐煤、烟煤和无烟煤三种代表性煤种的单次LN2冻融（LNSFT）和多次冻融循环（LNCFT）引起的力学和声学损伤。结果表明：孔隙水凝固初期增强了煤的强度和声完整性；随后，由冻胀、热应力和LN 2膨胀引起的裂纹萌生和扩展逐渐削弱了这些特性。这种强化与弱化之间的平衡主要是由煤的孔隙结构、裂隙和含水率决定的。加载作用下的声发射模式明显遵循稳态、激活和衰减阶段，冻结和融化阶段都促进了剪切导向裂缝的发育。由超声纵波速度(v)、峰值强度（σ）和弹性模量(E)计算的损伤指数(D)表明，冻融损伤程度与煤阶呈负相关，表明煤阶越高，结构稳定性和抗冻融能力越强。此外，在相同的累积冻结时间下，LNCFT造成的损伤明显大于LNSFT，突出了累积损伤效应。这些见解为优化旨在提高煤层渗透率的LN 2压裂技术提供了重要指导。

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引用次数: 0

Displacement analysis for energy pile foundations under thermomechanical loads 热力荷载作用下能量桩基础的位移分析

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-07-30 DOI: 10.1016/j.gete.2025.100725

Jincheng Fang , Shijin Feng , Yong Zhao , Hongxin Chen

Energy piles present an innovative energy-saving technology that can fulfill two critical building needs of structural support and energy supply. In practice, developing simple but efficient methods to predict the thermomechanical response of energy pile foundations is essential for geotechnical engineers. In this study, a practical method was proposed for the thermomechanical analyses of energy pile foundations. The proposed method could effectively describe the interactions between the grouped energy piles, the surrounding soil, and the stiff soil strata underlying the pile tip. Based on this method, parametric analyses were performed to evaluate the effects of several aspects, including the foundation geometries and ground properties, on the pile displacement behavior and the pile-to-pile interaction. Further, the proposed method was used for the displacement analysis for a square pile group containing sixteen energy piles under thermomechanical loads. Comparisons with results obtained through the experimental investigations and finite-element methods prove that the proposed method is capable of capturing the displacement response of energy pile foundations with reasonable accuracy. The aim of this study is to offer a practical method and a reliable reference to geotechnical engineers during the design of energy pile foundations.

能源桩是一种创新的节能技术，能够满足建筑结构支撑和能源供应两大关键需求。在实际应用中，开发简单而有效的方法来预测能源桩基础的热力响应对岩土工程师来说是必不可少的。本文提出了一种实用的能量桩基础热力分析方法。该方法能够有效地描述成组能量桩与周围土体以及桩端下刚性土层之间的相互作用。基于该方法，进行了参数分析，以评估地基几何形状和地基性质等方面对桩位移行为和桩间相互作用的影响。并将该方法应用于包含16根能量桩的方桩群在热力荷载作用下的位移分析。通过与试验研究结果和有限元方法的比较，证明了该方法能够以合理的精度捕捉能源桩基础的位移响应。本文的研究旨在为岩土工程师在能源桩基础的设计中提供实用的方法和可靠的参考。

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引用次数: 0

Hydromechanical and geochemical behavior of a serpentinized harzburgite 蛇纹石化辉石的流体力学和地球化学行为

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-07-26 DOI: 10.1016/j.gete.2025.100727

Pouyan Asem , Vaughan Voller , Juerg Matter , Joseph F. Labuz

Many hydrogeological processes are influenced by fluid infiltration into low-porosity serpentinites and the corresponding coupled hydromechanical-geochemical response. The interpretation of these coupled processes requires detailed measurement of poromechanical parameters and careful water sampling and analysis. We measured the poroelastic properties that control the hydromechanical response - drained bulk modulus K, unjacketed bulk modulus

K_{s}'

, and Biot coefficient α - for a serpentinized harzburgite from the Semail ophiolite, Oman. For the Terzaghi effective mean stress of 2.0 <

P'

= P

- p

< 7.0 MPa, the poroelastic coefficients K and α exhibit effective mean stress dependency; the ranges are 17.0 < K < 25.6 GPa and 0.74 > α > 0.60. The unjacketed bulk modulus

K_{s}'

= 64.4 GPa is measured at

P'

= 0 MPa. These parameters are used to interpret the diffusion during pulse decay tests, showing that permeability varies with effective mean stress: 2 × 10⁻²² > k > 5 × 10⁻²² m². Water sampling and analysis of fluid composition provided data on the geochemical processes. The geochemical analyses suggest that no new carbonate and serpentine minerals formed after some 47 weeks of reaction.

流体渗入低孔隙度蛇纹岩及其相应的水力-地球化学耦合响应影响着许多水文地质过程。解释这些耦合过程需要详细测量孔隙力学参数和仔细的水采样和分析。我们测量了控制流体力学响应的孔隙弹性性质——排干体积模量K、未夹套体积模量Ks’和Biot系数α——来自阿曼Semail蛇绿岩的蛇纹石化辉石。当Terzaghi有效平均应力为2.0 < P′= P−P <； 7.0 MPa时，孔隙弹性系数K和α表现为有效平均应力依赖关系；范围是17.0 & lt; K & lt; 25.6绩点和0.74在α在0.60。在P' = 0 MPa时，测量了未夹套的体积模量Ks ' = 64.4 GPa。这些参数用于解释脉冲衰减试验中的扩散，表明渗透率随有效平均应力的变化而变化：2 × 10−22 >； k > 5 × 10−22 m2。对水的取样和流体成分的分析提供了地球化学过程的数据。地球化学分析表明，在大约47周的反应后，没有形成新的碳酸盐和蛇纹石矿物。

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引用次数: 0

Hydro-mechanical and homogenization behaviour of GMZ bentonite pellets/block assemblies upon hydration GMZ膨润土球团/块团在水化作用下的水力学和均质行为

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-07-26 DOI: 10.1016/j.gete.2025.100726

Zhang-Rong Liu , Wei-Min Ye , He-Hua Zhu , Yong-Gui Chen , Qiong Wang

Bentonite pellets and block are jointly used to construct engineered barrier systems in geological repository. The hydro-mechanical behavior and homogenizations of bentonite pellets/block assemblies are of significant concern to the long-term operational safety of the repository. In this study, Gaomiaozi (GMZ) bentonite pellets were combined with block of different initial dry densities in three types of assemblies (I, II and III) and subjected to hydration under isochoric conditions. Evolutions of axial and lateral swelling pressures as well as local water contents and dry densities were measured. The pore structures of specimens after different durations of hydration were detected and analyzed with resort to X-ray μCT and mercury intrusion porosimetry (MIP) techniques. Results show that, the development modes and final values of axial and lateral swelling pressures were highly dependent on the assembly type and the initial dry density of the block. Affected by wall friction and fabric anisotropy, the final lateral swelling pressure on the pellets side was higher than that on the block side and the final axial swelling pressure was in between. No significant water infiltration rate difference was observed among the three assembly types, due to water availability was limited by a thin layer of bentonite gels initially formed near to the specimen bottom and the inter-pellet pores were closed gradually by the swelling pellets. For all the three assembly types, after an initial hydration stage (> 72 h), the pellets zone was compressed by the swelling block zone and the pellets/block interface tended to bend/move towards the pellets side, leading to a rearrangement of pellets, closing of the inter-pellet pores, healing of the interface and thus homogenization of the specimen. The degree of homogenization was evaluated quantitatively to decrease with increasing hydration time using a relatively porosity homogenization index (RPHI). However, the residual heterogeneity still remained even after full saturation, indicating the homogenization will persist for a long term.

利用膨润土球团和膨润土块体共同构建地质储库工程屏障体系。膨润土颗粒/块体组件的水力学行为和均质化对储存库的长期运行安全具有重要意义。本研究将高庙子（GMZ）膨润土球团与不同初始干密度的块体组合成三种类型（I、II和III），并在等时程条件下进行水化。测量了轴向和侧向膨胀压力以及局部含水量和干密度的演变。采用x射线μCT和压汞孔隙测定（MIP）技术对不同水化时间下试样的孔隙结构进行了检测和分析。结果表明，轴向和侧向膨胀压力的发展模式和最终值与块体的组合类型和初始干密度密切相关。受壁面摩擦和织物各向异性的影响，颗粒侧最终侧胀压力高于块体侧，最终轴向膨胀压力介于两者之间。由于在试样底部附近最初形成的一层薄的膨润土凝胶限制了水分的可用性，并且颗粒间的孔隙逐渐被膨胀的颗粒所封闭，三种组合类型之间的入渗速率没有显著差异。对于所有三种组合类型，在初始水化阶段(>；72 h)，球团区被膨胀块区压缩，球团/块界面倾向于向球团一侧弯曲/移动，导致球团重排，球团间孔隙关闭，界面愈合，从而使试样均匀化。采用相对孔隙度均质指数（RPHI）定量评价均质程度随水化时间的增加而降低。然而，即使在完全饱和后，残余的非均质性仍然存在，表明均质化将长期存在。

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引用次数: 0

Soil-vegetation-atmosphere interaction for engineering applications: Recent multi-scale and multi-disciplinary insights 土壤-植被-大气相互作用的工程应用：最近的多尺度和多学科的见解

IF 3.7 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-07-26 DOI: 10.1016/j.gete.2025.100723

M. Cecconi , V. Tagarelli , F. Cotecchia , V. Pane , F. Anselmucci , I. Bertolini , G. Biondi , D. Boldrin , V. Capobianco , G. Cardile , S. Cuomo , P. De Vita , A. Fraccica , G. Meijer , L. Pagano , M. Pirone , M. Schwarz , A. Tarantino , J. Vaunat , A. Yildiz

The paper presents some of both recent and previous outcomes on soil-vegetation-atmosphere mechanisms and processes. Contributions from several authors across different scientific fields, each focusing on specific aspects of soil and plant behaviour under variable climatic conditions, highlight the urgency of multi- and inter-disciplinarily research aimed at the investigation, analysis, and modelling of soil-vegetation-atmosphere (SVA) interaction. The paper focuses on different aspects of such interaction, which plays the crucial role of a thermo-hydro-mechanical boundary condition acting at the ground surface and controlling the transient behaviour of every geotechnical system. Some specific remarks and novel aspects of such interaction, analysed at increasing levels of complexity, are depicted in the paper through a multi-disciplinary point of view and according to a multi-scale methodology.

本文介绍了近年来有关土壤-植被-大气机制和过程的一些研究成果。来自不同科学领域的几位作者的贡献，每个人都关注不同气候条件下土壤和植物行为的具体方面，强调了针对土壤-植被-大气（SVA）相互作用的调查、分析和建模的多学科和跨学科研究的紧迫性。本文重点讨论了这种相互作用的不同方面，这种相互作用在地表起着热-水-力学边界条件的关键作用，并控制着每个岩土系统的瞬态行为。本文通过多学科的观点和多尺度的方法，在日益复杂的层次上分析了这种相互作用的一些具体评论和新方面。

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引用次数: 0

The nucleation of injection-induced earthquakes on low-permeability strike-slip faults 低渗透走滑断层上注入地震的成核

IF 3.3 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-07-22 DOI: 10.1016/j.gete.2025.100713

David Santillán , Cristina Vila , Juan Carlos Mosquera , Luis Cueto-Felgueroso

The injection of fluids into underground formations may induce damaging earthquakes and increase the sensitivity of injection sites to remote triggering. If the fault constitutive behavior and geomechanical conditions permit the development of a frictional instability, slip may eventually accelerate and trigger a coseismic slip event. We investigate the frictional and hydromechanical mechanisms that control the slip instability preceding an induced earthquake, the nucleation phase. Understanding fault reactivation and the transition from quasi-static aseismic slip to dynamic rupture is an important objective, as the nucleation phase may provide the key to detect preseismic signals and estimate the magnitude of the resulting earthquake. Our simulations show that poroelasticity coupling delays the onset of slip and dynamic rupture and creates asymmetric slip and pressure distributions on the fault. Our results indicate that pressure-driven nucleation patterns, while qualitatively similar to those of tectonic earthquakes in elastic media, are controlled by flow processes and poroelastic couplings that favor nucleation-zone expansion. Our numerical results suggest that nucleation lengths

L

for induced events scale proportional to the classical scaling

L_{\infty} = \frac{b}{{(b - a)}^{2}} \frac{G^{'} D_{c}}{σ_{n}^{^{'}}}

and time to nucleation with

L^{2}

. Moreover, since

τ_{n u c} \sim L^{2}

and

L \sim L_{\infty}

, then

τ_{n u c} \sim L_{\infty}^{2}

. A longer nucleation phase leads to higher pore pressures and a weaker fault at the onset of dynamic rupture.

向地下地层注入流体可能引起破坏性地震，并增加注入点对远程触发的敏感性。如果断层的本构行为和地质力学条件允许摩擦不稳定的发展，滑动可能最终加速并触发同震滑动事件。我们研究了控制诱发地震前的滑动不稳定性的摩擦和流体力学机制，即成核阶段。了解断层再活化和从准静态地震滑动到动态破裂的转变是一个重要的目标，因为成核阶段可能为探测震前信号和估计地震震级提供关键。我们的模拟表明，孔隙弹性耦合延迟了滑动和动态破裂的发生，并在断层上造成了不对称的滑动和压力分布。我们的研究结果表明，压力驱动的成核模式虽然在性质上与弹性介质中的构造地震相似，但受流动过程和孔隙弹性耦合的控制，有利于成核带的扩展。我们的数值结果表明，诱导事件的成核长度L与经典标度L∞=b(b−a)2G ‘ dcσ n ’成核时间与L2成核成核时间成正比。此外，由于τnuc ~ L2和L ~ L∞，则τnuc ~ L∞2。成核阶段越长，在动态破裂开始时孔隙压力越大，断层越弱。

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引用次数: 0

Erosion mechanism of subsea tunnel considering non-linear seepage and linearly varying permeability coefficient with time 考虑非线性渗流和渗透系数随时间线性变化的海底隧道侵蚀机理

IF 3.3 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-07-19 DOI: 10.1016/j.gete.2025.100722

Xiang Liu , Bangmeng Fu , Kuichen Li , Annan Jiang , Qian Fang , Jianye Li

The erosion mechanism of the subsea tunnel is complicated due to the unique submarine environment. Most research assumes the fluid follows Darcy's law and neglects the increasing permeability coefficient of the grouting zone with continuous chloride ion erosion. However, the grouting and lining zones exhibit relatively high density, causing the deviation of flow seepage from Darcy's law to non-Darcy's law. This paper aims to accurately study the erosion mechanism under non-Darcy seepage condition using Hansbo's non-linear seepage model. The entire erosion process is divided into three stages: (a) initial erosion, (b) developed erosion, and (c) rapid erosion. The focus is on investigating the erosion mechanism during the developed erosion stage, in which the grouting zone follows the linear segment of Hansbo's non-linear seepage law and the lining zone follows the curved segment under relatively high-water levels. The analytical solutions for the erosion depth and ion concentration are obtained, considering the linearly varying permeability coefficient of the grouting zone over time. Our proposed method is validated through the numerical simulation and established solution. In addition, parametric analyses are conducted including the service time and change of the permeability coefficient. It reveals that the pore pressure and erosion depth at different locations of the grouting zone increase approximately linearly as the water head acting on the ground surface increases. The erosion depth and ion concentration increase with the service time, with the most significant impact observed at the tunnel invert. A greater impact on the concentration is found closer to the surface of the grouting zone. The erosion depth is deeper considering the linearly varying permeability coefficient rather than a constant. However, the influence on ion concentration is minimal.

由于独特的海底环境，海底隧道的侵蚀机理十分复杂。大多数研究假设流体遵循达西定律，忽略了氯离子持续侵蚀灌浆区渗透系数的增加。但注浆区和衬砌区密度较大，导致渗流从达西定律向非达西定律偏离。本文旨在利用Hansbo非线性渗流模型准确研究非达西渗流条件下的侵蚀机理。整个侵蚀过程可分为三个阶段：(a)初始侵蚀，(b)发育侵蚀和(c)快速侵蚀。重点研究了高水位条件下，发育侵蚀阶段注浆区遵循Hansbo非线性渗流规律的线段，衬砌区遵循曲线段的侵蚀机理。考虑灌浆区渗透系数随时间的线性变化，得到了侵蚀深度和离子浓度的解析解。通过数值模拟和建立的解验证了所提方法的有效性。此外，还进行了服役时间、渗透系数变化等参数分析。结果表明：注浆区不同位置的孔隙压力和侵蚀深度随着地表水头的增大而近似线性增大；随着使用时间的延长，侵蚀深度和离子浓度增加，其中对隧道仰拱的影响最为显著。靠近注浆区表面对浓度的影响更大。考虑线性变化的渗透系数而不是常数时，侵蚀深度更深。然而，对离子浓度的影响很小。

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引用次数: 0

An engineering elastoplastic anisotropic model applied to the modelling of deep tunnelling in Opalinus Clay 将工程弹塑性各向异性模型应用于蛋白石粘土深部隧道的模拟

IF 3.3 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-07-17 DOI: 10.1016/j.gete.2025.100721

Aldo Madaschi , Julia Leuthold , Linard Cantieni , Silvio B. Giger , Lyesse Laloui

This paper introduces the Enhanced Anisotropic Damage Plasticity (eADP) model, a novel engineering constitutive approach tailored for tunnel analyses in Opalinus Clay – the designated host rock for the Swiss radioactive waste repository. The model's key innovations lie in its ability to comprehensively capture the complex behaviour of Opalinus Clay within an extremely efficient computational framework, making it suitable for routine engineering calculations and performance assessments. The eADP model adeptly reproduces Opalinus Clay's highly nonlinear stress-strain responses, accounting for anisotropic characteristics for stiffness, strength, and hardening. Honouring such complexity in material behaviour while keeping an efficient numerical performance was a key aspect of the eADP implementation. The model calibration relies on an extensive dataset derived from undrained triaxial tests performed on Opalinus Clay samples sourced recently from the Swiss candidate repository sites. The enhanced formulation and the multi-level optimisation scheme developed and applied in this work ensures a simple and robust parameter identification, showcasing the model's adaptability across varying loading conditions and confining pressures. The verification through hydromechanical computations at repository depths underscores the model's efficacy in realistic tunnel excavation scenarios.

本文介绍了增强各向异性损伤塑性（eADP）模型，这是一种新的工程本构方法，专门用于在蛋白石粘土中进行隧道分析，蛋白石粘土是瑞士放射性废物处置库的指定宿主岩石。该模型的关键创新在于它能够在一个极其高效的计算框架内全面捕捉Opalinus Clay的复杂行为，使其适用于常规工程计算和性能评估。eADP模型熟练地再现了蛋白石粘土的高度非线性应力应变响应，考虑了刚度、强度和硬化的各向异性特征。兼顾材料性能的复杂性，同时保持高效的数值性能是实现eADP的一个关键方面。模型校准依赖于一个广泛的数据集，该数据集来自对最近来自瑞士候选储库站点的Opalinus Clay样品进行的不排水三轴测试。在这项工作中开发和应用的改进配方和多级优化方案确保了简单而稳健的参数识别，展示了模型在不同加载条件和围压下的适应性。通过库深处的水力学计算验证了该模型在实际隧道开挖场景中的有效性。

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引用次数: 0

Creep characteristics and damage mechanisms of rock in the plateau tunnel: Insights from acoustic emission and energy evolution 高原隧道围岩蠕变特征与损伤机制：声发射与能量演化的启示

IF 3.3 2区工程技术 Q3 ENERGY & FUELS

Geomechanics for Energy and the Environment

Pub Date : 2025-07-16 DOI: 10.1016/j.gete.2025.100720

Yanzhe Li, Chuanxin Rong, Zhensen Wang, Yang Wang

The in-situ stress in plateau tunnels is significantly high and exhibits a complex distribution. Consequently, the long-term creep behavior of deep surrounding rock poses a critical challenge to the stability and integrity of tunnel engineering in plateau mountainous areas. To address this issue, this study performs triaxial creep tests on gneissic granite samples obtained from plateau tunnels under various stress paths. Additionally, the mechanical analysis is enhanced by incorporating acoustic emission characteristics and energy evolution. Two stress paths—continuous loading and confining pressure unloading—were implemented. Key parameters, including AE count, cumulative energy, and energy competition ratio R, were analyzed. The results indicate that: (1) Under the confining pressure unloading path, the accelerated creep stage duration,which just occupied 1.33 % of total loading time, was significantly shorter than that under continuous loading, with a 12.3 % reduction in failure strength, suggesting lower confinement facilitates microcrack propagation and rapid instability; (2) AE parameters and energy release patterns effectively characterized creep stages: steady-state creep exhibited steady AE activity, while abrupt increased in N and ΣE mark accelerated creep, with shear-dominated failure of over 69.9 %; (3) The energy competition ratio R grew exponentially beyond the critical deviatoric stress, though localized energy aggregation still triggered shear failure. This study elucidates how stress paths govern energy distribution and damage evolution, providing theoretical insights for stability assessment and disaster prevention in plateau tunnel engineering.

高原隧道地应力明显偏高，且分布复杂。因此，高原山区深部围岩的长期蠕变行为对隧道工程的稳定性和完整性提出了严峻的挑战。为了解决这一问题，本研究对高原隧道中获得的片麻岩花岗岩样品在不同应力路径下进行了三轴蠕变试验。此外，结合声发射特性和能量演化，增强了力学分析。采用连续加载和卸载围压两种应力路径。主要参数包括声发射计数、累积能量和能量竞争比R。结果表明：(1)围压卸载路径下，加速蠕变阶段持续时间仅占加载总时间的1.33 %，显著短于连续加载，破坏强度降低12. %，说明较低的约束有利于微裂纹扩展和快速失稳；(2)声发射参数和能量释放模式有效表征了蠕变阶段：稳态蠕变表现出稳定的声发射活性，而N和ΣE的突然增加标志着蠕变加速，剪切主导破坏率超过69.9% %；(3)在临界偏应力之后，能量竞争比R呈指数增长，但局部能量聚集仍会引发剪切破坏。该研究阐明了应力路径对能量分布和损伤演化的影响，为高原隧道工程稳定性评估和灾害防治提供了理论依据。

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引用次数: 0