Computers and Geotechnics最新文献_第10页

CFD–DEM comparison of slurry infiltration in laboratory column tests and in real-world tunnelling 实验室柱状试验和实际隧道工程中泥浆渗透的 CFD-DEM 比较

IF 5.3 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2024-10-05 DOI: 10.1016/j.compgeo.2024.106816

Jiayuan Liu, Kevin J. Hanley

Slurry infiltration and filter cake formation are critical for excavation surface stability in slurry shield tunnelling. Laboratory column tests are frequently adopted to study macroscopic infiltration. However, these tests, in a vertical orientation and confined by an impermeable cylindrical boundary, may not be a good representation of horizontal infiltration into an unbounded stratum in real-world tunnelling. In this paper, a more realistic slurry pressure balance (SPB) tunnelling model was created to overcome the limitations of simulated laboratory column tests. Coupled computational fluid dynamics (CFD)–discrete element method (DEM) numerical simulations were carried out to study the slurry infiltration into sand for this model and compare the results with the conventional laboratory column test model. Both models produced the same types of filter cakes. The SPB tunnelling model yielded larger infiltration distances and ranges, but a lower normalised permeability in the sand region in front of the tunnel face. The fluid pressure within this region dissipated much faster in the SPB tunnelling model, resulting in rapid velocity decreases and a faster infiltration process. Although the SPB tunnelling model is more representative of real-world tunnelling, the conventional laboratory column test is conservative, producing similar types of filter cakes over a longer timeframe.

泥浆渗透和滤饼形成对泥浆盾构隧道开挖面的稳定性至关重要。实验室柱状试验通常用于研究宏观渗透。然而，这些试验是在垂直方向上进行的，并被一个不透水的圆柱形边界所限制，可能不能很好地反映实际隧道工程中无边界地层的水平渗透情况。本文创建了一个更真实的泥浆压力平衡（SPB）隧道模型，以克服模拟实验室柱状试验的局限性。通过计算流体动力学（CFD）-离散元法（DEM）耦合数值模拟，研究了该模型的泥浆渗入砂中的情况，并将结果与传统的实验室柱状试验模型进行了比较。两种模型产生的滤饼类型相同。SPB 隧道模型产生了更大的渗透距离和范围，但隧道面前的沙区归一化渗透率较低。在 SPB 隧道模型中，该区域内的流体压力消散得更快，导致速度迅速降低，渗透过程更快。虽然 SPB 隧道模型更能代表真实世界的隧道情况，但传统的实验室柱状试验比较保守，在较长的时间范围内会产生类似类型的滤饼。

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引用次数: 0

Numerical study on the hydro-thermal-chemical–mechanical coupling mechanism in sulfate saline soil under freeze–thaw cycles 冻融循环条件下硫酸盐盐土的水热-化学-力学耦合机制数值研究

IF 5.3 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2024-10-04 DOI: 10.1016/j.compgeo.2024.106803

Jing Zhang , Yuanming Lai , Mingyi Zhang , Shuangyang Li , Dongqing Li , Zhemin You

Water-heat-salt migration inevitably leads to instability and failure in roads, slopes, channels, and tower foundations in sulfate saline soil regions undergoing freeze–thaw (F-T) cycles, severely compromising the safety and stability of long-term operations in cold region engineering. F-T tests were performed on sulfate saline soil under different F-T cycle modes to investigate the impact of F-T cycle frequency and cooling duration on water-salt transfer and soil deformation. This study revealed the coupled mechanism of water-heat-salt-mechanics in sulfate saline soil under variable F-T conditions and established a hydro-thermal-chemical–mechanical coupled model. The study indicates that the progression of salt spatiotemporal distribution during F-T cycles are initial salt accumulation in the frozen zone near the freezing front, an upward shift of the salt peak, salts redistribution as subflorescence and efflorescence, and surface salt accumulation. These factors are closely related to soil deformation. Longer cooling durations promote salt accumulation near the freezing front, while shorter durations and more F-T cycles encourage salt migration to the surface layer. The model’s reliability is validated by the good agreement between calculated results and experimental data. Understanding these multiphase-multifield coupling mechanism in sulfate saline soils can help address engineering issues associated with salt-frost heave.

水热盐迁移不可避免地会导致硫酸盐盐土地区的道路、边坡、渠道和塔基在冻融循环（F-T）过程中失稳和破坏，严重影响寒冷地区工程长期运行的安全性和稳定性。研究人员对不同冻融循环模式下的硫酸盐盐渍土进行了冻融试验，以研究冻融循环频率和冷却持续时间对水盐传递和土壤变形的影响。该研究揭示了不同 F-T 条件下硫酸盐盐土的水-热-盐-力学耦合机理，建立了水热-化学-力学耦合模型。研究表明，F-T 循环过程中盐分时空分布的变化过程为：冻结前沿附近冻结带的初始盐分积累、盐峰上移、盐分重新分布为亚沉积和渗出以及表层盐分积累。这些因素与土壤变形密切相关。较长的冷却时间会促进盐分在冻结前沿附近积累，而较短的冷却时间和较多的 F-T 循环则会促进盐分向表层迁移。计算结果与实验数据之间的良好一致性验证了模型的可靠性。了解硫酸盐盐土中的这些多相多场耦合机制有助于解决与盐冻隆起相关的工程问题。

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引用次数: 0

Analytical solution for radial consolidation of combined electroosmosis-vacuum-surcharge preloading considering free strain and cyclic loading 考虑自由应变和循环加载的电渗-真空-加载组合预加载径向固结的分析解决方案

IF 5.3 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2024-10-04 DOI: 10.1016/j.compgeo.2024.106810

Jing Zhang , Mengfan Zong , Wenbing Wu , Yi Zhang , Guoxiong Mei

In this study, electro-osmotic consolidation considering smear effect and free strain under cyclic loading was investigated. The analytical solution of radial consolidation of electroosmosis-vacuum-surcharge combined preloading is derived by using the Bessel function and eigenfunction methods. Subsequently, the effectiveness of the proposed method is validated through comparison with existing numerical solutions. Based on the derived solutions, the influence of the smear effect, applied voltage, vacuum pressure, and cyclic loading on soil consolidation characteristics was analyzed. The results showed that the smearing effect slows the rate of consolidation, but the final average consolidation and negative excess pore water pressure are enhanced. Compared with only cyclic loading, the combined effect of electroosmosis, vacuum, and surcharge preloading enables the soil to achieve higher strength and consolidation. When the effect of electroosmosis alone on reinforcing low-permeability soils is not significant, the combination of electroosmosis with vacuum preloading helps enhance the soil reinforcement effect.

本研究对循环加载下考虑涂抹效应和自由应变的电渗固结进行了研究。利用贝塞尔函数和特征函数方法推导出了电渗-真空-加载组合预加载径向固结的解析解。随后，通过与现有数值解的比较，验证了所提方法的有效性。根据推导出的解决方案，分析了涂抹效应、外加电压、真空压力和循环加载对土壤固结特性的影响。结果表明，涂抹效应减缓了固结速度，但最终平均固结度和负过剩孔隙水压力得到了提高。与只进行循环加载相比，电渗、真空和附加物预加载的综合效应可使土壤获得更高的强度和固结度。当单独使用电渗加固低渗透性土壤的效果不明显时，将电渗与真空预加载相结合有助于提高土壤加固效果。

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引用次数: 0

An analytical solution to ground stresses induced by tunneling considering ground surface boundary conditions and gravity 考虑地表边界条件和重力的隧道工程地应力分析法

IF 5.3 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2024-10-03 DOI: 10.1016/j.compgeo.2024.106806

Cheng-Cheng Zhang, Ren-Peng Chen, Huai-Na Wu, Fan-Yan Meng, Xin-Xin Yang

Accurately predicting the stress distribution around the tunnel is crucial for designing safe and economical support systems. The stress distribution is closely related to the ground stress release induced by tunneling, as well as the initial gravity stress and boundary conditions. In this study, a two-dimensional analytical model considering the ground surface boundary conditions and gravity is presented to investigate the stress field around the tunnel. Then, a numerical model was developed to validate the proposed analytical model. Finally, parametric analyses were conducted, and the limitations of the load calculation method of the code for design of shield tunnel in China were discussed. The results indicate that: (a) Tunnel excavation induces stress redistribution in the soil, resulting in a soil arching effect around the tunnel. This arching effect causes nonlinear load changes around the tunnel. (b) The soil mass around the tunnel can be divided into undisturbed and disturbed zones. Above the tunnel, the disturbance range is C-2D(C and D represent the burial depth and the tunnel diameter), while below and on both sides of the tunnel, the disturbance ranges are 4D and 1.5D, respectively. (c) Once the stress release rate reaches 0.6, a combined arching effect zone, consisting of both major and minor principal stresses, is formed in the disturbance zone above and below the tunnel. (d) The load distribution pattern calculated by the code for design of shield tunnel in China is gourd-shaped, and this calculation method is insufficient for accurately evaluating the load around the tunnel. The research results can provide a reference for the design of the shield tunnel.

准确预测隧道周围的应力分布对于设计安全、经济的支护系统至关重要。应力分布与隧道施工引起的地应力释放、初始重力应力和边界条件密切相关。本研究提出了一个考虑地表边界条件和重力的二维分析模型，以研究隧道周围的应力场。然后，开发了一个数值模型来验证所提出的分析模型。最后，进行了参数分析，并讨论了中国盾构隧道设计规范中荷载计算方法的局限性。结果表明(a) 隧道开挖引起土体应力重新分布，导致隧道周围土体产生起拱效应。这种起拱效应会导致隧道周围的荷载发生非线性变化。(b) 隧道周围的土体可分为未扰动区和扰动区。隧道上方的扰动范围为 C-2D（C 和 D 分别代表埋深和隧道直径），而隧道下方和两侧的扰动范围分别为 4D 和 1.5D。(c) 当应力释放率达到 0.6 时，隧道上方和下方的扰动区将形成由大主应力和小主应力组成的联合拱起效应区。(d) 我国盾构隧道设计规范计算的荷载分布模式为葫芦形，这种计算方法不足以准确评估隧道周围的荷载。研究成果可为盾构隧道的设计提供参考。

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引用次数: 0

Understanding the influence of drained cyclic preloading on liquefaction resistance of sands using DEM-clump modeling 利用 DEM-团块模型了解排水循环预加载对砂的抗液化性的影响

IF 5.3 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2024-10-03 DOI: 10.1016/j.compgeo.2024.106800

Siyuan Yang, Duruo Huang

The soils in situ are subjected to various types of preloading histories. Extensive work has been devoted to understanding the impact of undrained preloading with different strain histories on the reliquefaction resistance of sands. This study primarily examines the effects of drained cyclic preloading histories on the liquefaction resistance of soils using DEM-clump modeling. The effects of preloading stress path and preloading deviatoric stress amplitude on the drained cyclic behavior and subsequent undrained liquefaction response are discussed. Moreover, the evolution of two microscale descriptors, including coordination number Z and fabric anisotropy degree a_c, during the total process is analyzed. The results demonstrate that a smaller preloading stress amplitude and an increasing preloading cycle generally increase the liquefaction resistance of sandy soils. In comparison, a larger preloading stress amplitude significantly reduces the liquefaction resistance. We also reveal that drained cyclic preloading histories induce soil samples with different relative densities and fabrics. The relationship between relative density and liquefaction resistance of soils is not unique. Essentially, Z and a_c are good indexes for determining the liquefaction resistance of soils with various drained cyclic preloading histories. The primary objective of this study is to elucidate the micromechanical effects of drained cyclic preloading on the liquefaction resistance of sandy soils.

原地土壤会受到各种类型的预加载。为了了解不同应变历史的排水预加载对砂的抗再液化性的影响，已经开展了大量工作。本研究主要利用 DEM-团块模型研究排水循环预加载历史对土壤抗液化性的影响。研究讨论了预加载应力路径和预加载偏差应力振幅对排水循环行为和随后的非排水液化响应的影响。此外，还分析了整个过程中两个微观描述指标的演变，包括配位数 Z 和结构各向异性度 ac。结果表明，较小的预加载应力振幅和增加的预加载周期通常会提高砂土的抗液化能力。相比之下，较大的预加载应力振幅会明显降低抗液化能力。我们还发现，排水循环预加载历史会诱发具有不同相对密度和结构的土样。土壤的相对密度和抗液化性之间的关系并不是唯一的。从本质上讲，Z 和 ac 是确定不同排水循环预载历史的土壤抗液化性的良好指标。本研究的主要目的是阐明排水循环预载对砂土抗液化性的微观力学影响。

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引用次数: 0

Study on the characteristics of blast-induced damage zone by using the wave velocity field inversion technique 利用波速场反演技术研究爆破诱发损伤区的特征

IF 5.3 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2024-10-03 DOI: 10.1016/j.compgeo.2024.106808

Shuaiyang Fu , Haibo Li , Liwang Liu , Qian Li , Xiaofeng Li

The rock excavation by drilling and blasting method would lead to damage around the blasting hole, which could significantly affect the long-term stability of surrounding rock mass in tunnel, slope, or bedrock. To qualify the characteristics of blast-induced damage zone, we proposed a wave velocity field inversion imaging method, which combines multistencils fast marching methods and simultaneous iterative reconstructive technique to quickly inverse and quantify the blast-induced cracked zone surrounding the borehole. The finite-discrete element method, which has advantages in simulating the fracture and fragmentation of rocks, was used to simulate the blasting process and acoustic wave testing. The ground vibrations induced by the blasting were monitored simultaneously and the acoustic waveforms are used to invert the wave velocity field before and after blasts. The inverted wave velocity field is compared with the blast-induced cracked zone, and the relationship between the radius of the crushed zone and the cracked zone under different charges was studied. It is found that the ratio of the crushed zone radius and the cracked zone radius decreases with the increasing charge. Moreover, the relationship between the peak particle velocity at 30 m away from the borehole (PPV₃₀) and the distribution of the cracked zone was determined.

钻孔爆破法开挖岩石会导致爆破孔周围产生破坏，从而严重影响隧道、边坡或基岩周围岩体的长期稳定性。为了确定爆破诱发破坏带的特征，我们提出了一种波速场反演成像方法，该方法结合了多线性快速行进方法和同步迭代重建技术，可快速反演和量化钻孔周围的爆破诱发裂缝带。有限离散单元法在模拟岩石断裂和破碎方面具有优势，被用于模拟爆破过程和声波测试。同时监测爆破引起的地面振动，并利用声波波形反演爆破前后的波速场。将反演后的波速场与爆破引起的裂缝区进行比较，并研究了不同装药量下破碎区半径与裂缝区半径之间的关系。结果发现，破碎区半径与开裂区半径之比随着装药量的增加而减小。此外，还确定了距钻孔 30 米处的峰值颗粒速度（PPV30）与裂缝区分布之间的关系。

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引用次数: 0

Probabilistic back analysis of reservoir landslide considering hydro-mechanical coupled observations 考虑水力机械耦合观测的水库滑坡概率回溯分析

IF 5.3 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2024-10-01 DOI: 10.1016/j.compgeo.2024.106798

Yang Xue , Fasheng Miao , Jingze Li , Yiping Wu , Linwei Li

Precisely assessing statistical parameters to characterize spatial soil variability presents a significant challenge in probabilistic slope stability analysis, primarily due to inherent soil uncertainties and limited field-specific data. Probabilistic back analysis, recognized as an effective and reliable technique, offers a rational method for utilizing observational data to invert parameters of geomaterial properties. Nevertheless, previous investigations into parameter inversion for slope stability analysis have seldom considered the coupling of hydro-mechanical characteristics in reservoir landslides. This study proposes a novel integrated Bayesian framework to perform back analysis of reservoir landslides, incorporating the spatial variability of hydro-mechanical parameters. Within this framework, a hypoplastic constitutive model is developed to characterize the step-like deformation of the reservoir slope. The posterior knowledge of the saturated permeability coefficient and shear strength parameters is obtained by collecting field monitoring data of the underground water level and ground displacement. The Maliulin landslide, located in the Three Gorges Reservoir area of China, is adopted as an illustrative example to validate the proposed framework through back analysis of spatially variable soil parameters and probabilistic stability analysis. The results demonstrate that the proposed Bayesian updating framework significantly reduces the uncertainties associated with statistical values of soil parameters, providing more accurate and reasonable updated soil parameters for probabilistic slope stability analysis.

主要由于土壤固有的不确定性和有限的现场特定数据，精确评估统计参数以描述土壤空间变异性是边坡稳定性概率分析中的一项重大挑战。概率回溯分析被认为是一种有效可靠的技术，它为利用观测数据反演土工材料特性参数提供了一种合理的方法。然而，以往用于斜坡稳定性分析的参数反演研究很少考虑水库滑坡中的水力机械特性耦合问题。本研究提出了一种新颖的综合贝叶斯框架，用于对水库滑坡进行反演分析，其中纳入了水力机械参数的空间变异性。在此框架内，开发了一种低塑性构造模型，用于描述水库边坡的阶梯状变形。通过收集地下水位和地面位移的实地监测数据，获得了饱和渗透系数和剪切强度参数的后验知识。以位于中国三峡库区的麻柳林滑坡为例，通过对空间可变土壤参数的回溯分析和概率稳定性分析，验证了所提出的框架。结果表明，所提出的贝叶斯更新框架显著降低了与土壤参数统计值相关的不确定性，为边坡稳定性概率分析提供了更准确、更合理的更新土壤参数。

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引用次数: 0

DEM modeling of granular soils reinforced by disposable face-mask chips 用一次性面罩芯片加固颗粒土的 DEM 建模

IF 5.3 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2024-10-01 DOI: 10.1016/j.compgeo.2024.106804

Mengmeng Wu , Zhen-Yu Yin , Yuze Sun , Yue Li , Jianfeng Wang

The use of disposable masks, especially in the wake of the COVID-19 pandemic, has led to an increased focus on sustainable disposal and recycling methods. This study investigates the feasibility of integrating shredded mask materials into granular soils to enhance their mechanical properties for engineering applications. After validating the selection of Discrete Element Method (DEM) contact parameters through the conducted physical experiments, a comprehensive series of DEM simulations was performed to explore the effects of various mask contents on the mechanical behavior of sand-mask chip mixtures (e.g., soil’s strength and dilatancy) under different confining pressures. Additionally, the study analyzed the potential of mask chips in improving soil fabric, reducing contact force concentrations under shearing, and contributing to the soil’s stability. The results suggest that waste face masks could serve as a valuable resource for soil stabilization. This not only provides a viable solution for mask waste management but also introduces a novel, eco-friendly material that could improve the engineering properties of granular soils. The findings underscore the importance of understanding the interaction between waste masks and soil and open new pathways for the recycling of non-biodegradable waste in geotechnical applications.

一次性口罩的使用，尤其是在 COVID-19 大流行之后，使人们越来越关注可持续处置和回收方法。本研究探讨了将切碎的口罩材料整合到粒状土壤中的可行性，以增强其在工程应用中的机械性能。在通过物理实验验证了离散元素法（DEM）接触参数的选择后，进行了一系列全面的 DEM 模拟，以探索在不同约束压力下，各种掩模含量对砂土-掩模碎屑混合物力学行为（如土壤强度和膨胀性）的影响。此外，研究还分析了掩膜片在改善土壤结构、减少剪切作用下的接触力集中以及促进土壤稳定性方面的潜力。研究结果表明，废弃口罩可作为土壤稳定的宝贵资源。这不仅为口罩废物管理提供了一个可行的解决方案，还引入了一种新型环保材料，可改善颗粒土的工程特性。这些发现强调了了解废弃面膜与土壤之间相互作用的重要性，并为在岩土工程应用中回收不可降解的废弃物开辟了新的途径。

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引用次数: 0

An improved two phases-two points SPH model for submerged landslide 改进的淹没式滑坡两相两点 SPH 模型

IF 5.3 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2024-10-01 DOI: 10.1016/j.compgeo.2024.106802

Guibin Zhang , Danling Tang , Hongjie Wen , Jianyun Chen , Pengfei Wu

This research proposes an improved two phases-two points SPH model designed to simulate interactions between water and soil, particularly suitable for scenarios such as submerged landslides. This model treats water as a weakly compressible Newtonian fluid and soil as a cohesive-frictional material following an elastoplastic constitutive law, utilizing two layers of SPH particles to separately represent these two phases. An adaptive drag force formula is proposed that automatically switches between linear and nonlinear seepage modes based on the motion state of the porewater. Additionally, to improve the precision and stability of the model, a modified solid boundary condition and a method for calculating soil volume fraction are proposed, along with an SPH discretization formula that incorporates the effects of the volume fraction in a more effective way. The reliability of the improved two phases-two points SPH model is initially verified through two cases: a dry granular landslide and a submerged soil mass subjected to gravitational loading. Then, the effectiveness of the proposed improvement methods is further tested and validated through three submerged landslide cases with different grain diameters, demonstrating the applicability of the current model in simulating submerged landslides and its superiority in accuracy and stability compared to previous models.

本研究提出了一种改进的两相两点 SPH 模型，旨在模拟水与土壤之间的相互作用，尤其适用于淹没式滑坡等情况。该模型将水视为弱可压缩牛顿流体，将土视为内聚摩擦材料，遵循弹塑性结构定律，利用两层 SPH 粒子分别代表这两个阶段。提出的自适应阻力公式可根据孔隙水的运动状态在线性和非线性渗流模式之间自动切换。此外，为了提高模型的精度和稳定性，还提出了修改后的固体边界条件和计算土壤体积分数的方法，以及更有效地考虑体积分数影响的 SPH 离散化公式。通过两种情况初步验证了改进后的两相两点 SPH 模型的可靠性：干粒状滑坡和承受重力荷载的水下土体。然后，通过三个不同颗粒直径的淹没式滑坡案例进一步测试和验证了所提改进方法的有效性，证明了当前模型在模拟淹没式滑坡中的适用性，以及与之前模型相比在精度和稳定性方面的优越性。

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引用次数: 0

A novel constitutive model of the anisotropic sand accounting for the fabric evolution 各向异性砂的新型结构模型，考虑到织物的演变

IF 5.3 1区工程技术 Q1 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers and Geotechnics

Pub Date : 2024-09-30 DOI: 10.1016/j.compgeo.2024.106797

Zhicheng Gao , Pengcheng Ma , Yao Tang , Yunmin Chen , Qiang Ma

The mechanical behavior of the sand is affected by anisotropy. This paper presents a novel constitutive model for anisotropic sand that accounts for fabric evolution. In this proposed model, a novel hardening parameter and a new state variable are introduced to capture the effects of the evolving anisotropic fabric. A universal fabric tensor evolution law, independent of specific fabric tensors, is proposed based on the characteristics of the unified hardening model and the findings from discrete element simulations. Additionally, a dilatancy anisotropy compression line (DACL) is defined to compute the state variable, ensuring the uniqueness of the critical state line (CSL). The proposed model has been validated through a large number of monotonic shear datasets obtained from experiments and DEM simulations, while parameters in this proposed model are physically meaningful and easy to be determined. Analysis of fabric evolution under different loading paths indicates that the undrained triaxial compression test is the most effective for reaching the critical state, providing a useful reference for the critical state soil mechanics.

砂的力学行为受到各向异性的影响。本文针对各向异性砂提出了一种新的结构模型，该模型考虑了砂的结构演变。在该模型中，引入了一个新的硬化参数和一个新的状态变量，以捕捉各向异性结构演变的影响。根据统一硬化模型的特点和离散元模拟的结果，提出了一种独立于特定织物张量的通用织物张量演化规律。此外，还定义了扩张各向异性压缩线（DACL）来计算状态变量，确保临界状态线（CSL）的唯一性。通过实验和 DEM 模拟获得的大量单调剪切数据集验证了所提出的模型，同时该模型中的参数具有物理意义，易于确定。对不同加载路径下织物演变的分析表明，不排水三轴压缩试验对达到临界状态最为有效，为临界状态土壤力学提供了有益的参考。

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引用次数: 0