Engineering Geology最新文献_第8页

Forecasting CO2 injection-induced fault reactivation: A hybrid approach and its application to the Illinois Basin–Decatur Project 预测二氧化碳注入引起的断层再活化：一种混合方法及其在伊利诺斯盆地-迪凯特项目中的应用

IF 8.4 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

Engineering Geology

Pub Date : 2026-01-02 DOI: 10.1016/j.enggeo.2025.108536

Yao Zhang , Qi Li , Jianhua Zhang , Haodong Cui , Yiyan Zhong , Yongsheng Tan , Meng Jing , Xiaying Li

Geological CO₂ storage (GCS) is an effective method for reducing carbon emissions. However, as more such projects are deployed in the future, the associated risks of injection-induced fault reactivation require comprehensive assessment to ensure long-term and effective CO₂ storage. This study presents an integrated assessment of the Illinois Basin–Decatur Project (IBDP) through a hybrid approach combining physics-based modeling and probabilistic forecasting. A coupled CO₂-geomechanical model is developed to simulate CO₂ injection at CCS1 well. The fault reactivation risks have been systematically evaluated by analyzing near-well and far-field fault slip tendency indices, spatiotemporal evolution of Coulomb failure stress (CFS), seismogenic index (Σ), and magnitude probability distributions. Results demonstrate that while permeability-controlled pore pressure diffusion dominates fault reactivation for both near-well and far-well faults, poroelastic stresses may induce localized fault slip and provide stabilization during shut-in periods. The reactivation state is significantly controlled by fault geometry. Higher initial injection rates substantially facilitate fault instability compared to constant or gradually increasing injection schemes. Based on field data, the applicability of the seismogenic index for carbon storage sites has been validated. The low seismogenic index (Σ ≈ −4) for this site confirms limited seismic potential, and the probability of seismic magnitude below 2.27 exceeds 50%. Probabilistic modeling further indicates that a controlled injection rate ramp-up preferentially induces seismicity with low magnitudes. The proposed hybrid forecasting approach enables a more comprehensive evaluation of fault reactivation risks at carbon storage sites.

地质CO2封存是减少碳排放的有效方法。然而，随着未来更多此类项目的部署，需要对注入引起的断层重新激活的相关风险进行全面评估，以确保长期有效的二氧化碳储存。本研究通过结合物理建模和概率预测的混合方法，对伊利诺斯盆地-迪凯特项目（IBDP）进行了综合评估。建立了模拟CCS1井CO2注入过程的CO2-地质力学耦合模型。通过分析近井和远场断层滑动趋势指数、库仑破坏应力（CFS）时空演化、发震指数（Σ）和震级概率分布，系统评价了断层再激活风险。结果表明，虽然渗透率控制的孔隙压力扩散主导着近井和远井断层的恢复，但孔隙弹性应力可能会导致局部断层滑动，并在关井期间提供稳定。再激活状态在很大程度上受断层几何形状的控制。与恒定或逐渐增加的注入方案相比，较高的初始注入速率大大促进了断层的不稳定性。根据实测资料，验证了孕震指数在碳库选址上的适用性。本区孕震指数（Σ≈−4）较低，地震潜力有限，发生2.27级以下地震的概率超过50%。概率模型进一步表明，控制注入速度的增加优先诱发低震级的地震活动。提出的混合预测方法能够更全面地评估碳储存地点的断层再激活风险。

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引用次数: 0

Earthquake-triggered landslide susceptibility modeling based on fault geometry 基于断层几何的地震诱发滑坡易感性建模

IF 8.4 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

Engineering Geology

Pub Date : 2026-01-02 DOI: 10.1016/j.enggeo.2025.108539

Yigen Qin, Dongli Zhang, Wenjun Zheng, Xinyuan Chen, Xin Sun, Zhikang Gong

The geometric configurations and kinematic behavior of seismogenic faults fundamentally govern the spatial distribution of earthquake-triggered landslides, where quantifying their mechanisms dominating occurrence probability poses a core challenge for advancing predictive accuracy. Focusing on the 2008 Wenchuan earthquake and its main rupture zone (Beichuan–Yingxiu Fault), a thrust–strike–slip structure exhibiting along-strike dip variations ranging from ∼43° in the south to near-vertical in the north, this study establishes a probabilistic framework integrating fault geometry with five controlling factors, including distance to fault, peak ground acceleration (PGA), slope, local relief, and lithology, using a comprehensive EQTL inventory. Using multivariate nonlinear regression (MNR) and random forest (RF) modeling, we elucidate the fault dip's regulatory role in earthquake-triggered mechanisms. Key findings indicate that low-dip faults (43°–53°) drive concentrated hanging-wall landslides, characterized by PGA saturation > 0.5 g, high sensitivity to slopes >30°, and abrupt acceleration beyond 500 m relief; conversely, high-dip faults (59°–89°) exhibit bilaterally symmetric distributions with PGA triggering at 0.2 g, pronounced slope sensitivity >20°, and peak probability at 500–1000 m relief followed by post-peak decline. Factor importance analysis confirms distance to fault and PGA as primary predictors; however, their influence is dynamically modulated by dip angle. The RF model outperforms MNR (AUC >0.90 versus MNR's high-dip AUC = 0.728). Blind testing with the 2013 Lushan earthquake (thrust-type) and 2017 Jiuzhaigou earthquake (strike-slip) confirms the model captures hanging-wall concentration and bilateral symmetric distributions, demonstrating cross-fault adaptability.

发震断层的几何形态和运动行为从根本上控制着地震诱发滑坡的空间分布，而对其机制进行量化控制是提高预测精度的核心挑战。以2008年汶川地震及其主断裂带（北川-映秀断裂）为研究对象，建立了断层几何形状与断层距离、峰值地面加速度（PGA）、坡度、局部起伏和岩性等5个控制因素相结合的概率框架。北川-映秀断裂是一个逆冲-走滑构造，其沿走向倾角变化范围从南部的~ 43°到北部的接近垂直。利用多元非线性回归（MNR）和随机森林（RF）模型，阐明了断层倾角在地震触发机制中的调节作用。主要研究结果表明：低倾断层（43°~ 53°）驱动集中上盘滑坡，其特征为PGA饱和度0.5 g，对坡度30°高度敏感，起伏大于500 m时陡增；相反，高倾断层（59°-89°）呈现双边对称分布，PGA在0.2 g触发，明显的坡度敏感性>；20°，峰值概率在500-1000 m起伏处，然后是峰后下降。因子重要性分析证实断层距离和PGA是主要预测因子；然而，它们的影响是由倾角动态调制的。RF模型优于MNR （AUC >0.90，而MNR的高倾角AUC = 0.728）。利用2013年芦山地震（逆冲型）和2017年九寨沟地震（走滑型）进行盲测，证实该模型捕捉到了上盘集中和两侧对称分布，具有跨断层适应性。

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引用次数: 0

Distribution-free estimation for three-dimensional diameter of rock discontinuities within complex high-steep slope based on Bertrand paradox 基于Bertrand悖论的复杂高陡边坡岩体结构面三维直径无分布估计

IF 8.4 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

Engineering Geology

Pub Date : 2026-01-02 DOI: 10.1016/j.enggeo.2025.108538

Sicong Wang , Shengyuan Song , Mingyu Zhao , Ziyue Xu , Yaoyao Jiang , Muye Ma , Haojie Li

Traditional diameter estimation methods rely on the assumption that the midpoint of trace is uniformly distributed along the diameter of discontinuities and require sampling planes to share the same strike. This limitation renders them inapplicable to high-steep rock slopes with complex topography and undulating slope surfaces. In this situation, accurately estimating the average diameter of discontinuities has become a critical issue that requires urgent resolution. This study proposes a novel hypothesis based on Bertrand paradox that the midpoint of traces is uniformly distributed within the discontinuity for the first time. A new implicit probability function model for two-dimensional trace length and three-dimensional diameter was reconstructed, and a discretized numerical method was used to estimate the numerical solution of average diameter. A distribution-free accurate correction method for the average diameter of discontinuities in complex high-steep slopes has been proposed for the first time. The new method effectively suppresses size bias while eliminating orientation bias. Extensive validation through 162 sets of simulated data confirms the robustness of the new method, with mean relative errors consistently maintain below 15 %. Systematically analyzed the impact of four key discontinuity parameters (dip direction, dip angle, diameter size, and diameter distribution type) on estimation errors and proposed selecting principles for estimation parameters. Furthermore, the mapping relationship of distribution between diameter and intersection trace length is further revealed. Finally, the new method was applied to a high-steep slope with a height difference of 959 m. The consistency between the estimated and actual survey results indicates the reliability of the new method in complex high-steep slope engineering. The research outcomes break through the technical bottleneck in accurate characterization of rock mass discontinuity sizes, provide important references for evaluating the shape parameters of non-circular discontinuities, and hold significant implications for stability evaluation of high-steep rock slopes in hard mountain areas.

传统的直径估计方法依赖于迹线中点沿不连续面直径均匀分布的假设，并要求采样平面共用同一走向。这种局限性使其不适用于地形复杂、坡面起伏的高陡岩质边坡。在这种情况下，准确估计不连续面平均直径已成为一个迫切需要解决的关键问题。本文首次提出了基于Bertrand悖论的轨迹中点均匀分布于不连续区内的新假设。重建了二维轨迹长度和三维轨迹直径的隐式概率函数模型，并采用离散化数值方法估计了平均直径的数值解。首次提出了复杂高陡坡面结构面平均直径的无分布精确校正方法。新方法有效地抑制了尺寸偏差，同时消除了取向偏差。通过162组模拟数据的广泛验证证实了新方法的鲁棒性，平均相对误差始终保持在15%以下。系统分析了倾角、倾角、直径大小、直径分布类型等4个关键不连续参数对估计误差的影响，提出了估计参数的选择原则。进一步揭示了直径与交点轨迹长度分布的映射关系。最后，将该方法应用于高差为959 m的高陡边坡。结果表明，该方法在复杂高陡边坡工程中的应用是可靠的。研究成果突破了岩体结构面尺寸精确表征的技术瓶颈，为非圆形结构面形态参数评价提供了重要参考，对硬山区高陡岩质边坡稳定性评价具有重要意义。

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引用次数: 0

Probabilistic characterization of 3D geotechnical variability by fusion of multi-fidelity measurements using Gaussian Process Regression 基于高斯过程回归的多保真度测量融合三维岩土变异性的概率表征

IF 8.4 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

Engineering Geology

Pub Date : 2025-12-30 DOI: 10.1016/j.enggeo.2025.108514

Tengyuan Zhao , Yatong Qi , Zi-Jun Cao , Ling Xu , Dong Wang , Wei Li

Characterization of three-dimensional (3D) subsurface geotechnical properties is essential for the safe design and analysis of geotechnical infrastructures. Due to the complex geological formation process, these properties exhibit strong spatial variability. However, because of time and budget constraints and/or limited technical access, high-fidelity measurements (e.g., standard penetration test, SPT) are typically sparse. Directly interpreting a 3D subsurface profile from such sparse high-fidelity data can lead to significant statistical uncertainty, which may propagate and compromise project safety. Meanwhile, although various low-fidelity measurements (e.g., geophysical data, measurements at similar geotechnical sites) are often available, they are not fully utilized in practice. This study proposes a Gaussian Process Regression (GPR)–based framework to fuse information from multi-fidelity measurements to facilitate the accurate characterization of site-specific 3D variability. The proposed method first trains separate Gaussian process models on each low-fidelity dataset and uses their combined predictions in a linear regression to approximate high-fidelity values. Next, a new GPR is used to fit the residuals to correct remaining discrepancy, producing a final calibrated estimate. The method is demonstrated on a synthetic 3D subsurface case and a real-world case. The results show the proposed method yields much lower prediction errors and uncertainty compared to using only the high-fidelity measurements, with

R^{2}

values improved by approximately 50%/443% and MSE reduced by about 36%/72% in the numerical/real-life case. A sensitivity study further verifies the robustness of the proposed framework, showing that the method proposed in this study is capable of accurately and efficiently characterizing 3D geotechnical variability by fusing of multi-fidelity measurements.

三维地下岩土特性的表征对于岩土基础设施的安全设计和分析至关重要。由于复杂的地质形成过程，这些性质表现出强烈的空间变异性。然而，由于时间和预算的限制和/或有限的技术访问，高保真度测量（例如，标准渗透测试，SPT）通常是稀疏的。直接从这种稀疏的高保真数据解释三维地下剖面可能会导致显著的统计不确定性，这可能会传播并危及项目安全。同时，虽然经常有各种低保真度的测量（例如地球物理数据、类似岩土工程地点的测量），但它们在实践中没有得到充分利用。本研究提出了一种基于高斯过程回归（GPR）的框架来融合来自多保真度测量的信息，以促进准确表征特定地点的三维变异性。该方法首先在每个低保真度数据集上训练单独的高斯过程模型，并在线性回归中使用它们的组合预测来近似高保真度值。接下来，使用新的探地雷达来拟合残差以纠正剩余的差异，产生最终的校准估计。该方法在一个合成三维地下案例和一个实际案例中进行了验证。结果表明，与仅使用高保真度测量值相比，该方法的预测误差和不确定性要低得多，在数值/实际情况下，R2值提高了约50%/443%，MSE降低了约36%/72%。灵敏度研究进一步验证了所提出框架的鲁棒性，表明本文提出的方法能够通过融合多保真度测量准确有效地表征三维岩土变化。

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引用次数: 0

Propagation of porous slurry veins in marine hydrate reservoirs via dual-enhanced fracture grouting 双重强化裂缝注浆对海洋水合物储层多孔浆脉扩展的影响

IF 8.4 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

Engineering Geology

Pub Date : 2025-12-30 DOI: 10.1016/j.enggeo.2025.108535

Yun Qi , Youhong Sun , Bing Li , Pengfei Xie , Hengfeng Shan , Xilong Liu , Guobiao Zhang

Unlike traditional fracture grouting methods for reinforcing soft soils, a novel technique known as Dual-enhanced fracture grouting (DEFG) has been proposed. By utilizing a specially designed dual-enhanced slurry in fracture grouting, which, upon solidification, forms high-strength, highly-permeable slurry veins within the reservoir. Marine hydrate reservoirs, with weak mechanical properties and poor permeability, exhibit low production efficiency, making this technique shows strong potential for enhancing gas production. To explore the effects of soil properties on fracture initiation and slurry diffusion, DEFG experiments were conducted on clayey-silty sediments with water saturation ranging from 40 % to 100 %, the slurry diffusion behavior was analyzed, and the morphology and pore structure of slurry veins were examined. The results showed that higher sediment cohesion and permeability increased initiation pressure, slurry diffused more easily in sediments with higher water saturation, leading to the formation of more slurry vein wings and a larger coverage area. Porosity analysis showed that the slurry veins have a porosity of about 60 % and are dominated by large pores (∼7.4 μm), with the proportion of macropores slightly increasing in sediments with higher water saturation, which exhibit excellent permeability. As the slurry veins develop into complex and widely distributed networks, their high porosity and large pore sizes promote efficient gas and water transport, ultimately enhancing the efficiency of hydrate extraction. These findings confirm the feasibility of DEFG technology for efficient hydrate development and demonstrate its potential as a new geotechnical approach for foundation reinforcement and drainage.

与传统的断裂注浆加固软土的方法不同，提出了一种新型的双强化断裂注浆（DEFG）技术。通过在裂缝注浆中使用特殊设计的双增强浆液，该浆液凝固后，在储层内形成高强度、高渗透性的浆液脉。海洋水合物储层力学性质弱、渗透率差，采收率低，具有很强的增产潜力。为探讨土体性质对裂缝起裂和浆液扩散的影响，在含水饱和度为40% ~ 100%的粘土-粉质沉积物中进行了DEFG实验，分析了浆液扩散行为，考察了浆液脉的形态和孔隙结构。结果表明：沉积物黏结力和渗透率越高，起爆压力越大，浆体在含水饱和度越高的沉积物中越容易扩散，形成较多的浆体脉翼，覆盖面积越大；孔隙度分析表明，浆液脉体孔隙度约为60%，以大孔隙（~ 7.4 μm）为主，在含水饱和度较高的沉积物中，大孔隙的比例略有增加，具有较好的渗透率。随着浆体矿脉发育成复杂且分布广泛的网络，其高孔隙率和大孔径促进了气、水的高效输运，最终提高了水合物提取效率。这些发现证实了DEFG技术有效开发水合物的可行性，并展示了它作为一种新的地基加固和排水岩土技术方法的潜力。

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引用次数: 0

Fracture evolution and differential mechanical response of surrounding rock in deep tunnel excavation: A case study under complex geological conditions 复杂地质条件下深部隧道开挖围岩裂隙演化与差异力学响应研究

IF 8.4 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

Engineering Geology

Pub Date : 2025-12-29 DOI: 10.1016/j.enggeo.2025.108534

Xiaojun Yu , Xizhi Zhang , Xia-Ting Feng , Feiyan Wang , Ming Shi , Chengxiang Yang , Huanzhen Luo , Yaping Yang , Yushan Wang

With the intensification of deep mineral extraction, deep tunnels increasingly suffer from large deformations due to high in-situ stress, complex geology, and multi-field coupling, rendering traditional support systems ineffective. Taking the 790 m-level tunnel of Jinchuan Mine as a case study, this research investigates the fracture evolution mechanisms of surrounding rock in deep tunnels under complex geological conditions. An innovative “ahead-lag complementary monitoring network” was established, integrating borehole television (BTV), multipoint extensometers, and hollow inclusion strain gauges to systematically capture fracture responses in three typical rock types: intact hard rock, mosaic-fragmented rock, and fault zones. Results show that pre-existing fractures begin to reactivate approximately 1.6D ahead of the tunnel face (where D is the tunnel span) and stabilize at a depth of ∼5 m, exceeding the effective anchorage range of standard bolt support. New fractures initiate within ±0.4D of the face and extend ∼2 m. Fracture propagation is strongly influenced by the spatial distribution of adverse geological structures. Based on these findings, differentiated support strategies are proposed: conventional support for intact rock; pre-grouting +5 m deep self-expanding bolts + grouting for mosaic-fragmented rock; and double-layer support + deep reinforcement for fault zones. This study clarifies the progressive failure process in deep tunnels and provides a theoretical and practical basis for controlling large deformations under complex geological conditions. This work establishes a comprehensive framework linking excavation-induced stress redistribution to fracture evolution across multiple rock types, offering new insights and practical strategies for large-deformation control in deep, complex geological environments.

随着深部矿产开采力度的加大，深部巷道因地应力高、地质复杂、多场耦合等原因造成的大变形日益严重，传统支护系统失效。以金川矿790 m级隧道为例，研究复杂地质条件下深部隧道围岩破裂演化机制。建立了一个创新的“超前滞后互补监测网络”，将井眼电视（BTV）、多点延伸仪和空心包裹体应变仪集成在一起，系统地捕捉了三种典型岩石类型（完整硬岩、镶嵌破碎岩和断裂带）的裂缝响应。结果表明：原有裂缝在巷道工作面前方约1.6D处（D为巷道跨度）开始恢复活动，并在~5 m处稳定，超出了标准锚杆支护的有效锚固范围；新的裂缝在工作面±0.4D内开始，延伸~2 m。裂缝扩展受不利地质构造空间分布的强烈影响。在此基础上，提出了不同的支护策略：对完整岩石进行常规支护；预注浆+5 m深自膨胀锚杆+镶嵌破碎岩体注浆；断层带双层支撑+深层加固。该研究阐明了深埋隧道的渐进破坏过程，为复杂地质条件下控制大变形提供了理论和实践依据。这项工作建立了一个综合框架，将开挖引起的应力重新分布与多种岩石类型的裂缝演化联系起来，为深部复杂地质环境中的大变形控制提供了新的见解和实用策略。

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引用次数: 0

Nano-SiO₂ modified microbial-induced carbonate precipitation: Application in altered rock fracture zone reinforcement and strengthening mechanism 纳米sio2改性微生物诱导碳酸盐沉淀在蚀变岩破碎带加固中的应用及加固机理

IF 8.4 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

Engineering Geology

Pub Date : 2025-12-29 DOI: 10.1016/j.enggeo.2025.108531

He-rui Zhao , Quan Jiang , Yong Xia , Dong-qi Hou , Ding-ping Xu

Microbial-induced carbonate precipitation (MICP) represents a highly promising biogrouting approach for ground improvement. Most research efforts have been concentrated on the application of MICP in treating soil. In contrast, research about the application of MICP in altered rock fracture zone is limited. Moreover, nano-SiO₂ (NS), a common additive, has been little research on assisting MICP. In this study, the strengthening effect of NS on the MICP for reinforcing the altered rock fracture zone was studied. The mechanical strength tests and microstructural analysis were carried out. The results showed that after adding NS, the uniaxial compressive strength (UCS), cohesion, and friction angle were all higher than those of non-NS added groups. The maximum UCS, cohesion, and friction angle occurred when the NS concentration was 10 mg/L. Their maximum values were 3.46 MPa, 380.7 kPa, and 32.66°, respectively, representing increases of 190 %, 113 %, and 33 % compared to the non-NS added groups. After MICP treatment, due to the releasing

{Mg}^{2 +}

from chlorite and illite, the original structure of the altered rock particles is damaged, and the cohesion is significantly decreased. The addition of NS can significantly compensate for the weakening effect of MICP on the cohesion. In XRD (X-ray diffraction) and SEM (scanning electron microscope) analysis, silicate gel phases were observed. These gels work in tandem with calcium carbonate precipitation to further enhance the mechanical properties. Meanwhile, the adsorption and nucleation effect of NS can regulate the calcium ion concentration in the environment, provide new nucleation sites for

CaC O_{3}

, thereby promoting the accumulation and precipitation of

CaC O_{3}

and further enhancing the strength of the altered rock fracture zone.

微生物诱导碳酸盐沉淀（MICP）是一种非常有前途的生物灌浆方法。大多数研究工作都集中在MICP在土壤处理中的应用上。相比之下，MICP技术在蚀变岩体破碎带中的应用研究较少。此外，纳米sio2 （NS）作为一种常用的助剂，在辅助MICP方面的研究较少。本研究研究了NS对蚀变岩破碎带MICP的加固作用。进行了机械强度试验和显微组织分析。结果表明：添加NS后，单轴抗压强度（UCS）、黏聚力、摩擦角均高于未添加NS组；当NS浓度为10 mg/L时，单抗强度、内聚力和摩擦角最大。它们的最大值分别为3.46 MPa、380.7 kPa和32.66°，分别比未添加ns组增加了190%、113%和33%。MICP处理后，由于绿泥石和伊利石释放Mg2+，蚀变后岩石颗粒的原有结构被破坏，粘聚力明显降低。NS的加入可以明显地弥补MICP对黏聚力的减弱作用。在XRD （x射线衍射）和SEM（扫描电子显微镜）分析中，观察到硅酸盐凝胶相。这些凝胶与碳酸钙沉淀物协同工作，进一步提高了机械性能。同时，NS的吸附成核作用可以调节环境中的钙离子浓度，为CaCO3提供新的成核位点，从而促进CaCO3的富集和沉淀，进一步增强蚀变岩破碎带的强度。

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引用次数: 0

From mineral dissolution to slope failure: wet-dry cycling driven multiscale degradation of Cenozoic red-bed mudstone, NE Tibetan Plateau 从矿物溶解到边坡破坏：青藏高原东北缘新生代红层泥岩干湿循环驱动的多尺度退化

IF 8.4 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

Engineering Geology

Pub Date : 2025-12-29 DOI: 10.1016/j.enggeo.2025.108530

Yezi Quan , Zuopeng Wang , Jianbing Peng , Yiguo Xue , Mingdong Zang , Yan Lv , Ruihao Ning , Changming Lu , Chao Xue

Extensive Cenozoic red-bed mudstone, highly susceptible to slope failure, is distributed across the NE Tibetan Plateau. These rocks undergo progressively deterioration under repeated wet–dry cycling (WDC) driven by intense seasonal rainfall, ultimately forming slip surfaces. However, the multiscale mechanisms governing this deterioration and instability remain poorly understood. To address this, we applied a multiscale investigation integrating field observations, X-ray diffraction (XRD), scanning electron microscopy (SEM), computed tomography (CT), triaxial testing, and numerical modeling. The results reveal the evolution of red-bed mudstone under WDC, from mineral dissolution and pore expansion to fracture interconnection, stress concentration, and mechanical degradation. Key findings include: (1) Differential dissolution of clay minerals (e.g., kaolinite) and feldspar increases the porosity from 1.8 % to 16.3 %, triggering the initial deterioration; (2) WDC further raises the porosity from 9.8 % to 16.9 %, interconnects isolated fractures into a continuous network, and enhances permeability from 10.2 × 10⁻⁶ to 561.9 × 10⁻⁶ Darcy, accelerating internal structural degradation; (3) This evolving degradation network induces stress concentration, leading to a 84 % reduction in strength (from 8905.68 to 1419.85 kPa) and a 79.5 % reduction in cohesion (from 1931.4 to 395.8 kPa), substantially weakening the slope stability; (4) At the slope scale, an “externally dry, internally wet” structure develops, where the coupled effects of mineral dissolution, pore evolution, permeability enhancement, and strength loss drive a progressive creep failure, characterized by external fracturing and internal softening. Thus, this study establishes a multiscale coupled evolution model and elucidates how WDC induces differential sliding in red-bed slopes, providing a theoretical basis for landslide prediction in such regions.

青藏高原东北部分布着广泛的新生代红层泥岩，极易发生边坡破坏。这些岩石在强烈的季节性降雨驱动下，在反复的干湿循环（WDC）下逐渐退化，最终形成滑动面。然而，控制这种恶化和不稳定的多尺度机制仍然知之甚少。为了解决这个问题，我们应用了多尺度调查，包括现场观测、x射线衍射（XRD）、扫描电子显微镜（SEM）、计算机断层扫描（CT）、三轴测试和数值模拟。研究结果揭示了WDC作用下红层泥岩从矿物溶解、孔隙扩张到裂缝互联、应力集中、力学降解的演化过程。主要发现包括：(1)粘土矿物（如高岭石）和长石的差异溶蚀使孔隙度从1.8%增加到16.3%，引发了初始变质；(2) WDC进一步将孔隙度从9.8%提高到16.9%，将孤立裂缝连成一个连续的网络，渗透率从10.2 × 10−6达西提高到561.9 × 10−6达西，加速了内部构造的降解；(3)这种演化的退化网络引起应力集中，导致边坡强度降低84%（从8905.68 kPa降低到1419.85 kPa），粘聚力降低79.5%（从1931.4 kPa降低到395.8 kPa），显著削弱了边坡的稳定性；(4)在边坡尺度上，形成“外干内湿”的结构，矿物溶解、孔隙演化、渗透性增强和强度损失的耦合作用推动了以外裂内软化为特征的渐进式蠕变破坏。因此，本研究建立了一个多尺度耦合演化模型，阐明了WDC对红层边坡微分滑动的影响，为该地区的滑坡预测提供了理论依据。

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引用次数: 0

Multiscale damage mechanisms of reservoir bank sandstone under prolonged immersion in pumped-storage hydropower projects: From microscale processes to macroscopic fracture 抽水蓄能水电站长时间浸没下库岸砂岩多尺度损伤机理：从微观过程到宏观断裂

IF 8.4 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

Engineering Geology

Pub Date : 2025-12-28 DOI: 10.1016/j.enggeo.2025.108532

Hexing Zhang , Qiang Xie , Jiwei Jia , Kunpeng Lu , Fubo Yang , Weichen Sun

The long-term stability of pumped-storage reservoir banks is strongly governed by damage evolution induced by prolonged water immersion. In this study, reservoir bank sandstone from the Laowuji pumped-storage site in Guizhou, China, was examined using computerized tomography (CT), nuclear magnetic resonance (NMR), scanning electron microscopy (SEM), and molecular dynamics (MD) simulations to systematically characterize damage evolution from the mesoscopic to microscopic scales and to elucidate cascade effects across multiple scales. After 360 days of immersion, the mineral cement interface dissolution area increased from 12.51 μm² to 139.83 μm². Porosity rose from 9.45 % to 10.95 %, the small-pore fraction decreased to 80.11 %, and medium-to-large pores increased significantly, enhancing pore connectivity and heterogeneity. Concurrently, the P-wave velocity decreased cumulatively by 45.99 %, indicating a high sensitivity to microstructural degradation. MD simulations revealed that mineral interfaces weaken chemical bonding while providing lubricated and dilatable pathways, thereby facilitating early microcrack initiation and rapid propagation, ultimately compromising reservoir bank integrity and reducing seepage safety margins. The three-dimensional fracture spatial inhomogeneity index (FSI_3D) increased by more than an order of magnitude over 360 days, capturing the transition of fracture patterns from relatively simple through-going cracks to a complex, interconnected fracture network. On this basis, a zoned management strategy consisting of “shallow-sealing and deep-infiltration control” and a multi-parameter dynamic early warning system is proposed. These findings provide theoretical support and engineering guidance for long-term stability control of reservoir bank sandstone in pumped-storage systems.

抽水蓄能库岸的长期稳定性受长期浸水损伤演化的强烈影响。本研究利用计算机断层扫描（CT）、核磁共振（NMR）、扫描电镜（SEM）和分子动力学（MD）模拟技术，对贵州老五集抽水蓄能区储层砂岩进行了研究，系统地表征了从细观到微观尺度的损伤演化过程，并阐明了跨多个尺度的级联效应。浸泡360 d后，矿物水泥界面溶解面积由12.51 μm2增加到139.83 μm2。孔隙度由9.45%上升至10.95%，小孔隙率下降至80.11%，中大型孔隙显著增加，孔隙连通性和非均质性增强。同时，纵波速度累计下降45.99%，表明其对微观结构降解具有较高的敏感性。MD模拟显示，矿物界面在提供润滑和可膨胀通道的同时削弱了化学键，从而促进了早期微裂缝的形成和快速扩展，最终损害了储层的完整性，降低了渗流安全裕度。三维裂缝空间不均匀性指数（FSI3D）在360天内增加了一个多数量级，捕捉到了裂缝模式从相对简单的贯通裂缝到复杂、相互连接的裂缝网络的转变。在此基础上，提出了“浅封深控”分区治理策略和多参数动态预警系统。研究结果为抽水蓄能系统库岸砂岩的长期稳定控制提供了理论支持和工程指导。

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引用次数: 0

Forecasting seismic rockfalls through a fragility–antifragility and topographic–anisotropic framework: The 2022 Ms. 6.1 Lushan earthquake 利用脆弱-反脆弱和地形-各向异性框架预测地震落石：2022年芦山6.1级地震

IF 8.4 1区工程技术 Q1 ENGINEERING, GEOLOGICAL

Engineering Geology

Pub Date : 2025-12-27 DOI: 10.1016/j.enggeo.2025.108533

Yonghong Luo , Gerardo Grelle , Qiang Xu

Landslide hazard in seismically active mountainous regions is a dynamic variable influenced not only by seismic intensity but also by the structural setting of slopes and by the modes of energy release from seismic sources. It is further conditioned by the spatial distribution of past slope instabilities recorded in the region's seismic history. This study thoroughly explores this complex interaction, proposing a novel framework for near-real-time forecasting of rockfall hazard, tested on the 2022 Ms. 6.1 Lushan earthquake. The approach integrates seismic anisotropies in wave propagation and polarization with topographic amplification and introduces a new conceptual model of pre-induced resilience, emerging from the interplay between fragility and antifragility as phenomena controlling residual resilience. Back-analysis of observed rockfalls, avalanches, and flows distributions reveals that sectors previously affected by slope instabilities, particularly following the 2013 Ms. 7.0 event, exhibit signs of induced antifragility, which in some cases has limited or even prevented the triggering of new failures during the 2022 event. In contrast, areas with fault-parallel slope orientations and transverse topographic amplification display a significant concentration of large-scale failures, especially where long-wavelength seismic loads interact with deep fractured zones. These findings underscore the key role of dynamic shear transmission and structural slope conditions in modulating landslide hazard. The proposed framework offers a physics-based, scalable method for forecasting slope failures in seismically active mountain regions, with strong implications for early warning systems and risk mitigation strategies.

地震活跃山区的滑坡灾害是一个动态变量，不仅受地震烈度的影响，还受边坡结构设置和震源能量释放方式的影响。这进一步受到该地区地震历史中记录的过去边坡不稳定性的空间分布的制约。本研究深入探讨了这种复杂的相互作用，提出了一个近实时岩崩灾害预测的新框架，并在2022年芦山6.1级地震中进行了测试。该方法将地震波传播和极化的各向异性与地形放大相结合，并引入了一种新的预诱导弹性概念模型，该模型是从脆性和反脆性之间的相互作用中产生的，作为控制剩余弹性的现象。对观察到的岩崩、雪崩和流动分布的反向分析显示，之前受边坡不稳定影响的部分，特别是在2013年7.0级事件之后，表现出诱发反脆弱性的迹象，在某些情况下，这限制了甚至阻止了2022年事件中引发新的失败。相比之下，断层平行坡向和横向地形放大的区域显示出大规模破坏的显著集中，特别是在长波长地震载荷与深部裂缝带相互作用的区域。这些发现强调了动力剪切传递和结构边坡条件在调节滑坡危害中的关键作用。提出的框架提供了一种基于物理的、可扩展的方法，用于预测地震活跃山区的边坡破坏，对早期预警系统和风险缓解策略具有重要意义。

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引用次数: 0