Computers and Geotechnics最新文献_第7页

Ground failure mechanism for deep tunnel in sandy cobble strata based on the cohesive zone element 基于黏聚带单元的砂卵石地层深部隧道地表破坏机理

IF 6.2 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2026-05-01 Epub Date: 2026-02-02 DOI: 10.1016/j.compgeo.2026.107955

Pei Zhang , Chengru Yang , Chao Ma , Jie Yang , Xiuli Du

Sandy cobble strata exhibit pronounced heterogeneity and a discrete nature. Clarifying the ground failure mechanism during shield tunneling in such strata has great theoretical significance and practical values. In this paper, based on the cohesive zone element, a numerical analysis method for simulating tunnel excavation under dynamic explicit algorithm is established. In the approach, the dissipation of ground energy, the implementation of tunnel excavation and the establishment of the initial stress field under the explicit algorithm are three crucial points. For the first point, the Rayleigh damping was used to achieve the input or output of ground energy. For the second point, a user-defined field variable subroutine was compiled to simulate tunnel excavation by reducing the element stiffness of excavation zone. For the third point, the “trial and error” method was used to determine the required analysis time for the geostatic step. Then, through simulating a physical model test on tunnel excavation in boulder-cobble mixed formations, the applicability of the proposed method was verified. The results show that the proposed method can effectively capture the progressive failure process and instability range of ground. Subsequently, the proposed method was extended to investigate the ground failure mechanism for deep circular tunnel in sandy cobble strata. The progressive failure process of ground was reproduced, and the stages of instability evolution was clarified. Combined with the distribution density of failed cohesive zone elements, the development of the collapse arching and the soil pressure arching were clarified. It was found that the outer boundary of collapse arching can be described by a parabolic curve, and the outer boundary of soil pressure arching can be described by an elliptical curve. Furthermore, a detailed parametric analysis was carried out to explore the influence of ground conditions on the failure zones.

砂卵石地层具有明显的非均质性和离散性。阐明此类地层盾构掘进过程中地表破坏机理具有重要的理论意义和实用价值。本文基于内聚区单元，建立了动态显式算法下隧道开挖模拟的数值分析方法。在该方法中，地表能量的耗散、隧道开挖的实施和显式算法下初始应力场的建立是三个关键点。对于第一点，采用瑞利阻尼来实现地面能量的输入或输出。针对第二点，编写了自定义场变量子程序，通过降低开挖区单元刚度来模拟隧道开挖。对于第三点，使用“试错法”来确定地静力步骤所需的分析时间。然后，通过对石卵石混合地层隧道开挖的物理模型模拟试验，验证了所提方法的适用性。结果表明，该方法能有效地捕捉地基的渐进破坏过程和失稳范围。随后，将该方法推广到砂卵石地层中深埋圆形隧道地面破坏机理的研究中。再现了地基的逐步破坏过程，明确了失稳演化的阶段。结合破坏黏结带单元的分布密度，阐明了崩塌拱和土压拱的发展过程。研究发现，崩塌拱的外边界可以用抛物线曲线来描述，土压拱的外边界可以用椭圆曲线来描述。此外，还进行了详细的参数分析，探讨了地面条件对破坏区域的影响。

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引用次数: 0

Permeability prediction of porous media with non-circular pores using a modified Kozeny–Carman equation enhanced by fractal theory 基于分形理论的改进Kozeny-Carman方程非圆孔多孔介质渗透率预测

IF 6.2 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2026-05-01 Epub Date: 2026-02-11 DOI: 10.1016/j.compgeo.2026.107960

Di Feng , Fengxiang Luo , Bin Chen , Yuan Wang

The Kozeny–Carman (K–C) equation and its variants have been widely used for permeability prediction in geotechnical engineering, but their prediction accuracy is often compromised by the assumption of circular pore shape. To enhance the accuracy of the K–C equation and clarify the influences of structural parameters on the porous media permeability, we derive a novel fractal analytical model for permeability and K–C constant, which incorporates irregular pore shape and contains no empirical constants. The fractal analytical model for permeability and K–C constant is related to parameters including the average pore shape factor, the pore size distribution fractal dimension, the tortuosity fractal dimension, the maximum pore diameter, and porosity. Based on the publicly available digital core data, the predictions of the new model were compared with those of other permeability equations, validating the effectiveness and applicability of the proposed model. We analysed the influence of the average pore shape factor on dimensionless permeability and K–C constant. An increase in the average pore shape factor leads to a nonlinear decrease in K–C constant and a nonlinear increase in dimensionless permeability. The influence of pore shape irregularity on permeability aligns with physical principles. Sensitivity analysis using the Sobol method was conducted on the parameters affecting permeability and K–C constant. The results indicate that accurately determining K–C constant by obtaining precise values for the pore size distribution fractal dimension, the average pore shape factor, and the tortuosity fractal dimension is key to reducing permeability prediction errors. In summary, the novel fractal analytical model established in this study can enhance the prediction accuracy of permeability for porous media with non-circular pores, further reveal the fluid transport mechanisms in such media, and provide a more solid theoretical foundation for geotechnical engineering and related fields.

Kozeny-Carman （K-C）方程及其变体已广泛用于岩土工程渗透率预测，但其预测精度往往受到圆形孔隙形状假设的影响。为了提高K-C方程的准确性，明确结构参数对多孔介质渗透率的影响，我们推导了一种新的渗透率和K-C常数分形分析模型，该模型考虑了不规则孔隙形状，不包含经验常数。渗透率和K-C常数的分形分析模型与平均孔隙形状因子、孔径分布分形维数、扭曲度分形维数、最大孔径、孔隙度等参数有关。基于公开的数字岩心数据，将新模型的预测结果与其他渗透率方程的预测结果进行了比较，验证了该模型的有效性和适用性。分析了平均孔隙形状因子对无因次渗透率和K-C常数的影响。平均孔隙形状因子的增加导致K-C常数的非线性降低和无因次渗透率的非线性增加。孔隙形状不均匀对渗透率的影响符合物理原理。采用Sobol法对影响渗透率和K-C常数的参数进行敏感性分析。结果表明，通过精确获取孔隙尺寸分布分形维数、平均孔隙形状因子和弯曲度分形维数来准确确定K-C常数是减小渗透率预测误差的关键。综上所述，本研究建立的新型分形分析模型可以提高非圆孔多孔介质渗透率的预测精度，进一步揭示非圆孔多孔介质中流体的运移机理，为岩土工程及相关领域提供更坚实的理论基础。

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引用次数: 0

A random simplified analysis method to evaluate braced excavation-induced wall deflection considering spatial variability of soil 考虑土体空间变异性的支挖墙挠度随机简化分析方法

IF 6.2 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2026-05-01 Epub Date: 2026-01-23 DOI: 10.1016/j.compgeo.2026.107917

Xiaolu Gan , Nianwu Liu , Jin Guo , Wenbo Li , Jianlin Yu , Xiaonan Gong

The wall deflection in braced excavations is inevitably and significantly influenced by the inherent spatial variability of soil parameters, and the applicability of current beam-spring model-based simplified methods becomes severely constricted when considering soil spatial variability. Therefore, a random simplified analysis method for the evaluation of the braced excavation-induced wall deflection in spatially variable soil is proposed in this paper. The deterministic model is established based on an improved beam-spring model that incorporates spatial variations in soil parameters, and its finite difference solution is derived. The spatial variability of soil parameters is characterized by the lognormal random field, which is further discretized using the Karhunen–Loève expansion method. The sparse polynomial chaos expansion is employed to construct an efficient metamodel for rapid random analysis. The effectiveness of the proposed method is demonstrated through a case study of a well-documented braced excavation project. Random analysis results reveal that the variability in the normalized maximum wall deflection initially decreases and then increases, while that in its position increases abruptly before progressively decreasing, due to the coupled effect of the increased excavation depth and the addition of internal supports. The ignorance of the soil spatial variability may result in overestimation of the variability in the normalized deflection and underestimation of that in its position. The presented methodology provides a useful reference for the uncertainty analysis of excavation-induced wall deflection during preliminary design stages.

土体参数固有的空间变异性对支撑式基坑墙体挠度的影响是不可避免的和显著的，在考虑土体空间变异性时，现有基于梁-弹簧模型的简化方法的适用性受到严重限制。因此，本文提出了一种评价空间变土中支撑开挖引起的墙体挠度的随机简化分析方法。在考虑土壤参数空间变化的改进梁-弹簧模型的基础上，建立了确定性模型，并推导了其有限差分解。土壤参数的空间变异性表现为对数正态随机场，并采用karhunen - lo展开法对其进行离散化。利用稀疏多项式混沌展开构造了一个快速随机分析的有效元模型。所提出的方法的有效性通过一个有充分记录的支撑挖掘项目的案例研究来证明。随机分析结果表明，由于开挖深度增加和内支护的耦合作用，归一化最大墙体挠度的变异性先减小后增大，而其位置的变异性先增大后逐渐减小。对土壤空间变异性的忽视可能导致对归一化挠度变异性的高估和对其位置变异性的低估。该方法为初步设计阶段开挖引起的墙体挠度的不确定性分析提供了有益的参考。

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引用次数: 0

Fully coupled physics-informed neural networks for hydro-mechanical analysis of saturated poroelastic media 饱和孔隙弹性介质流体力学分析的全耦合物理信息神经网络

IF 6.2 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2026-05-01 Epub Date: 2026-02-02 DOI: 10.1016/j.compgeo.2026.107954

S. Akhyani, B. Shahbodagh, N. Khalili

A physics-informed neural networks (PINNs) framework is presented for the fully coupled hydro-mechanical analysis of saturated poroelastic materials. Continuous-time PINNs are developed that simultaneously solve the coupled momentum balance and mass conservation equations with no training data or spatial and time discretisation. The framework is validated against three benchmark hydro-mechanical problems with known analytical solutions: one-dimensional Terzaghi’s consolidation (linear and nonlinear elasticity, with a stress-dependent bulk modulus), De Leeuw’s cylindrical problem, and Cryer’s spherical problem. A key contribution is the implementation of a simultaneous optimisation strategy to capture the strong coupling between the mechanical and hydraulic fields, enabling accurate modelling of the Mandel–Cryer effect. Parametric studies are presented to demonstrate the robustness of the proposed approach across varying Poisson’s ratios and fluid bulk moduli.

提出了一种基于物理信息的神经网络（PINNs）框架，用于饱和孔隙弹性材料的完全耦合水力分析。在不需要训练数据或空间和时间离散化的情况下，开发了可以同时求解耦合动量平衡和质量守恒方程的连续时间pin n。该框架针对三个具有已知解析解的基准水力学问题进行了验证：一维Terzaghi固结（线性和非线性弹性，具有应力相关的体积模量），De Leeuw的圆柱形问题和Cryer的球形问题。一个关键的贡献是实现了同步优化策略，以捕获机械和液压场之间的强耦合，从而实现了曼德尔-克莱效应的精确建模。参数研究提出，以证明鲁棒性提出的方法跨越不同的泊松比和流体体积模量。

引用次数: 0

A numerical model for consolidation-induced contaminant transport in PVD-treated dredged sludge pvd处理疏浚污泥中固结诱导污染物运移的数值模型

IF 6.2 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2026-05-01 Epub Date: 2026-02-16 DOI: 10.1016/j.compgeo.2026.107994

Yutao Sun, Chuanxun Li

Installing prefabricated vertical drains (PVDs) can significantly accelerate the self-weight consolidation of contaminated dredged sludge and facilitate the discharge of contaminant within it. Modeling the consolidation-induced contaminant transport and its spatial distribution is critical for assessing pollution risks and implementing environmental monitoring at dredged sludge sites. However, existing models inadequately account for the realistic boundaries and the changes in soil properties caused by consolidation, thereby failing to accurately capture consolidation-induced contaminant transport in PVD-treated sites. Therefore, this study develops a numerical model for consolidation-induced contaminant transport in PVD-treated dredged sludge to simulate the contaminant transport under self-weight nonlinear consolidation. The developed model was verified by comparing it with data from experiments and existing models. Based on the proposed model, the effects of several key engineering parameters, such as the permeability of PVDs, installation spacing, and vacuum pressure, on the variations in contaminant concentrations at the site are analyzed. Numerical analysis reveals that PVD installation significantly accelerates contaminant removal, with the consolidation process contributing to 97.7% of the total removal rate over a five-year period. Increasing vacuum pressure or surcharge load, and reducing the installation spacing of PVDs can all accelerate the contaminant removal rate of the site. After the completion of consolidation, the advection becomes negligible and contaminant in the soil diffuse from high-concentration areas to the already cleaned zones and eventually achieve a uniform radial distribution. This model provides a quantitative tool for evaluating both the potential reuse of contaminated dredged sludge and the associated environmental risks at reclaimed sites.

安装预制垂直排水管可以显著加快受污染疏浚污泥的自重固结，促进污泥内污染物的排放。模拟固结引起的污染物迁移及其空间分布对于评估疏浚污泥场地的污染风险和实施环境监测至关重要。然而，现有的模型没有充分考虑到实际边界和固结引起的土壤性质变化，因此无法准确捕获pvd处理场地中固结引起的污染物迁移。因此，本研究建立了pvd处理疏浚污泥固结诱导污染物迁移的数值模型，模拟自重非线性固结下的污染物迁移。通过与实验数据和现有模型的比较，验证了所建模型的正确性。基于该模型，分析了PVDs渗透率、安装间距和真空压力等关键工程参数对现场污染物浓度变化的影响。数值分析表明，PVD安装显著加速了污染物的去除，在5年的时间里，固结过程对总去除率的贡献达到97.7%。提高真空压力或附加负荷，减小PVDs的安装间距，都可以加快现场的污染物去除率。固结完成后，平流变得可以忽略不计，土壤中的污染物从高浓度区域扩散到已经净化的区域，最终达到均匀的径向分布。这个模型提供了一个定量的工具来评估污染的疏浚污泥的潜在再利用和在填海地点的相关环境风险。

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引用次数: 0

Hierarchical constitutive modeling of structured clays: Bridging element tests and mechanized tunneling simulations 结构粘土的分层本构模型：桥接单元试验和机械化隧道模拟

IF 6.2 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2026-04-01 Epub Date: 2026-01-04 DOI: 10.1016/j.compgeo.2026.107902

Thomas Barciaga , Mahdi Taiebat , Maria Datcheva , Torsten Wichtmann

Mechanized tunneling in natural clays requires accounting for complex soil behavior governed by anisotropy, structure, stress–strain history, and destructuration. This paper develops a hierarchical constitutive modeling framework based on the SANICLAY family within critical state soil mechanics to simulate mechanized tunneling. The framework establishes a clear progression from element-scale model evaluation to boundary-value application, ensuring continuity between constitutive formulation, calibration, and three-dimensional tunnel simulation. Calibration is anchored in well-documented element test datasets and supported by variance-based global sensitivity analysis to identify influential parameters. The resulting calibrated models are then applied in three-dimensional finite element tunneling simulations across normally consolidated and overconsolidated states under both drained and undrained conditions. Results show that destructuration is the dominant mechanism for settlements, most evident in normally consolidated drained cases, while anisotropy and bounding-surface plasticity have more moderate and case-dependent impacts. The tunnel-scale analyses extend the calibrated framework to realistic excavation conditions, maintaining continuity between constitutive formulation and boundary-value response. The study provides practical guidance for model selection and calibration in structured clays, with implications for realistic prediction and the safe design of mechanized tunnels.

在天然粘土中进行机械化隧道掘进需要考虑复杂的土体特性，包括各向异性、结构、应力-应变历史和破坏。基于临界状态土力学SANICLAY族，建立了一种分层本构模型框架，用于模拟机械化隧道开挖过程。该框架建立了从元素尺度模型评估到边界值应用的清晰进展，确保了本构公式、校准和三维隧道模拟之间的连续性。校准是锚定在充分记录的元素测试数据集，并支持基于方差的全局敏感性分析，以确定有影响的参数。然后将校准后的模型应用于排水和不排水条件下正常固结和超固结状态下的三维有限元隧道模拟。结果表明，破坏是沉降的主要机制，在正常固结的排水情况下最为明显，而各向异性和界面塑性的影响较为温和，且与具体情况有关。隧道尺度分析将校准框架扩展到实际开挖条件，保持本构公式和边值响应之间的连续性。该研究为结构粘土模型的选择和标定提供了实用指导，对现实预测和机械化隧道的安全设计具有指导意义。

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引用次数: 0

Beyond depth-direction segregation: Independent flow-direction mechanisms drive size segregation in granular flows 超越深度方向偏析：独立的流动方向机制驱动颗粒流的尺寸偏析

IF 6.2 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2026-04-01 Epub Date: 2026-01-08 DOI: 10.1016/j.compgeo.2026.107901

Yuanjun Jiang , Yuanjia Zhu

Granular flows often exhibit size segregation along both the depth and flow-directions, yet the mechanisms driving segregation in the flow-direction remain poorly resolved. Using three-dimensional discrete element simulations, two intrinsic flow-direction segregation mechanisms that operate independently of depth-direction stratification: forward kinetic sieving, in which smaller particles advance due to higher granular temperature and geometric mobility, and shear-induced migration, in which larger particles with stronger contact networks transmit shear more efficiently and move forward. These mechanisms are distinct from secondary forward advection, where large particles elevated into faster surface layers by depth-direction segregation are subsequently carried downslope. The dominance of flow-direction segregation is shown to depend on the temporal stage of depth-direction structuring: forward kinetic sieving prevails during early stratification, whereas shear-induced migration governs once depth segregation stabilizes. Based on these insights, a continuum framework is developed that, for the first time, couples depth- and flow-direction segregation into a unified model, demonstrating strong agreement with simulation results. The findings clarify the bidirectional interplay of granular segregation and improve predictive modeling of hazard-related granular flows.

颗粒流通常在深度和流动方向上都表现出尺寸偏析，但在流动方向上驱动偏析的机制仍然没有得到很好的解决。通过三维离散元模拟，发现了两种独立于深度方向分层的内在流动方向偏析机制：正向动力筛分，其中小颗粒由于更高的颗粒温度和几何迁移率而前进；剪切诱导迁移，其中具有更强接触网络的大颗粒更有效地传递剪切并向前移动。这些机制不同于次级正向平流，在次级正向平流中，大颗粒通过深度方向偏析上升到更快的表层，随后被带到下坡。流向偏析的优势取决于深度方向构造的时间阶段：在分层早期，正向动力筛分盛行，而一旦深度偏析稳定下来，剪切诱导的运移起主导作用。基于这些见解，研究人员开发了一个连续体框架，首次将深度和流向分离耦合到一个统一的模型中，与模拟结果非常吻合。研究结果阐明了颗粒偏析的双向相互作用，并改进了与危险相关的颗粒流动的预测模型。

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引用次数: 0

A discrete element approach for simulating progressive fracturing in geothermal reservoirs via a new cohesive crack model 用一种新的内聚裂缝模型模拟地热储层递进压裂的离散元方法

IF 6.2 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2026-04-01 Epub Date: 2026-01-08 DOI: 10.1016/j.compgeo.2026.107908

Fei Wang , Dehao Meng , Heinz Konietzky , Eleni Gerolymatou , Paul W.J. Glover , Ben-Guo He

In fractured geothermal energy storage systems, repeated heating and cooling cycles and fluid interactions cause non-linear and non-monotonic fracture deformations, requiring sophisticated modeling of complex thermo-hydro-mechanical (THM) behaviors. This paper proposes a new cohesive crack model for the discrete element method (DEM), aiming to enhance the characterization of the entire fracturing process in rocks during loading–unloading-reloading while considering thermo-hydraulic conditions. Specifically, the model proposed allows for flexible adjustment of post-peak tension behavior and is able to capture the progressive evolution of fracture opening and closing under cyclic THM loadings. Validation of the new model was performed under a range of thermo-hydraulic conditions, confirming its ability to replicate diverse fracture behaviors, and offering a comprehensive solution to modeling the complex interplay of thermal, hydraulic, and mechanical factors influencing rock fractures in the context of geothermal energy storage and extraction systems.

在裂缝性地热储能系统中，反复的加热和冷却循环以及流体相互作用会导致非线性和非单调的裂缝变形，这需要对复杂的热-水-机械（THM）行为进行复杂的建模。本文提出了一种新的离散元法（DEM）内聚裂缝模型，旨在增强考虑热-水力条件下岩石加载-卸载-再加载整个破裂过程的表征。具体来说，所提出的模型允许灵活调整峰值后张力行为，并且能够捕捉到循环THM载荷下裂缝张开和闭合的渐进演变。在一系列热水力条件下对新模型进行了验证，确认了其复制不同裂缝行为的能力，并为地热储能和采掘系统中影响岩石裂缝的热、水力和机械因素的复杂相互作用建模提供了综合解决方案。

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引用次数: 0

Probabilistic stratigraphic modeling of waste soil landfills using multiple UAV data 基于多无人机数据的废土填埋场概率地层建模

IF 6.2 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2026-04-01 Epub Date: 2026-01-07 DOI: 10.1016/j.compgeo.2026.107903

Shuairong Wang , Shuai Zhang , Haoquan Wang , Hui Wang , Fan Zhang , Ping Shen , Wei Yan , Wenjun Zhang , Zhuofeng Li , Liangtong Zhan

Rapid urbanization has caused numerous waste soil landfills. While most stratigraphic modeling has focused on natural geological formations, the stratigraphic characteristics of man-made landfills remain underexplored, posing potential safety risks. This study aims to characterize the stratigraphic heterogeneity and model the stratigraphic configuration of waste soils using multiple unmanned aerial vehicle (UAV) data. The reverse stockpiling method, combined with a progressive front dumping strategy, forms inclined dumping surfaces and produces rotated anisotropic strata in landfills. A novel UAV-based stratigraphic modeling method is developed to encode these anisotropic features and perform the stratigraphic interpolation by integrating Markov random fields and Bayesian approaches. UAV imagery is used to interpret the spatial distribution of visible soils. Three anisotropic potential functions are custom-designed to reflect the spatial constraint structure of inclined strata. Bayesian model comparison approach identifies model parameters, i.e., spatial correlation lengths, and selects the most plausible potential functions and stratigraphic profiles. The method is validated through a real-world landfill case. Results show the largest spatial correlation length along the strike direction of the inclined surface, followed by the dip direction, and the smallest along the normal direction, reflecting the level of anisotropy. Simulated stratigraphic profiles align with the observed inclined stratum structure in fields. This study provides a new approach and a good dataset for modeling the stratigraphic heterogeneity of waste soil, contributing to the safety assessment of man-made landfills.

快速的城市化造成了大量的废土填埋。虽然大多数地层模拟都集中在自然地质构造上，但人造垃圾填埋场的地层特征仍未得到充分研究，存在潜在的安全风险。利用多架无人机（UAV）数据对废土的地层非均质性进行了表征，并建立了废土的地层构型模型。反向堆积法与前缘递进排土法相结合，形成倾斜排土面，并在填埋场内形成旋转各向异性地层。提出了一种新的基于无人机的地层建模方法，对这些各向异性特征进行编码，并结合马尔可夫随机场和贝叶斯方法进行地层插值。无人机图像用于解释可见土壤的空间分布。为反映倾斜地层的空间约束结构，定制了3个各向异性势函数。贝叶斯模型比较方法识别模型参数，即空间相关长度，选择最合理的潜在函数和地层剖面。通过实际垃圾填埋场实例验证了该方法的有效性。结果表明，沿倾斜面走向的空间相关长度最大，沿倾斜方向的空间相关长度次之，沿法向的空间相关长度最小，反映了各向异性的程度。模拟的地层剖面与现场观测到的倾斜地层结构一致。该研究为模拟废弃土壤的地层异质性提供了一种新的方法和良好的数据集，有助于人工填埋场的安全性评估。

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引用次数: 0

Numerical analysis of liquid-gas phase transition effects on pore clogging and particle transport 液气相变对孔隙堵塞和颗粒输运影响的数值分析

IF 6.2 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2026-04-01 Epub Date: 2025-12-23 DOI: 10.1016/j.compgeo.2025.107863

Tuo Wang , Mengmeng Wu , Zhen-Yu Yin , Xu-Guang Chen

This study investigates the impact of liquid–gas phase transition on pore clogging during supercritical carbon dioxide (SC-CO₂) geological storage. To address this, we developed a pore-scale CFD-DEM-VOF model incorporating phase transition. It is capable of simulating phase transition processes in multiphase flows and their subsequent effects on particle behavior, as well as the resulting coupled dynamics of particle transport, pore clogging, and unclogging. Throughout these simulations, drag forces, contact forces on particles, and the evolution of the flow field were meticulously tracked and analyzed. Crucially, the research employed both constant-velocity and constant-pressure inlet boundary conditions, using non-phase-transition models as controls for comparison. Analysis of the results revealed that phase transition influences particle behavior through two distinct mechanisms. Firstly, volume expansion accelerates particle transport towards pore outlets. Conversely, and simultaneously, phase transition enhances turbulence and vortex formation within the flow field. This secondary effect loosens particle clusters, slows their movement, and traps particles within swirling flow structures that impede passage. Under constant-velocity boundary conditions, higher phase transition rates generally promote faster particle transport through pores. In contrast, under constant-pressure conditions, phase transition reduces the inlet flow velocity at higher rates. Due to the low viscosity and density of gas, it is less effective at carrying particles through pores under these conditions. As a result, moderate phase transition rates yield the highest particle transport rates in the constant-pressure inlet model.

研究了超临界二氧化碳（SC-CO2）地质封存过程中液气相变对孔隙堵塞的影响。为了解决这个问题，我们开发了一个包含相变的孔隙尺度CFD-DEM-VOF模型。它能够模拟多相流中的相变过程及其对颗粒行为的后续影响，以及由此产生的颗粒输运、孔隙堵塞和易堵塞的耦合动力学。在这些模拟过程中，对阻力、颗粒接触力和流场的演变进行了细致的跟踪和分析。至关重要的是，该研究同时采用了等速和恒压进口边界条件，并使用非相变模型作为对照进行比较。分析结果表明，相变通过两种不同的机制影响粒子的行为。首先，体积膨胀加速了颗粒向孔出口的输运。相反，同时，相变增强了流场内的湍流和涡的形成。这种次级效应会使颗粒团松散，减缓它们的运动，并将颗粒困在阻碍通过的漩涡流结构中。在等速边界条件下，较高的相变速率通常促进颗粒更快地通过孔隙。相反，在恒压条件下，相变以较高的速率降低了进口流速。由于气体的粘度和密度较低，在这些条件下，通过孔隙携带颗粒的效率较低。因此，在恒压进口模型中，中等相变速率产生最高的颗粒输运速率。

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引用次数: 0