International Journal for Numerical and Analytical Methods in Geomechanics最新文献_第10页

Analytical Solutions for a Fully Coupled Hydraulic-Mechanical-Chemical Model With Nonlinear Adsorption 具有非线性吸附作用的全耦合水力-机械-化学模型的分析解决方案

IF 3.4 2区工程技术

International Journal for Numerical and Analytical Methods in Geomechanics Pub Date : 2024-09-17 DOI: 10.1002/nag.3829

Lin Han, Zhihong Zhang, Jiashu Zhou

{"title":"Analytical Solutions for a Fully Coupled Hydraulic-Mechanical-Chemical Model With Nonlinear Adsorption","authors":"Lin Han, Zhihong Zhang, Jiashu Zhou","doi":"10.1002/nag.3829","DOIUrl":"10.1002/nag.3829","url":null,"abstract":"<div>\u0000 \u0000 <p>Adsorption characteristics play a crucial role in solute transport processes, serving as a fundamental factor for evaluating the performance of clay liners. Nonlinear adsorption isotherms are commonly found with metal ions and organic compounds, which introduce challenges in obtaining analytical solutions for solute transport models. In this study, analytical solutions are proposed for a fully coupled hydraulic-mechanical-chemical (HMC) model that accounts for both the Freundlich and Langmuir isotherms. To mitigate the difficulties arising from the variable coefficients, the system of second-order partial differential equations involving three variables is linearized. The method of separation of variables, theory of integration, and Fourier series are utilized to derive analytical solutions. The analytical method presented can potentially be extended to a broad spectrum of nonlinear adsorption isotherms. The results reveal a 56.5% reduction in solute breakthrough time under the Freundlich isotherm and a remarkable 2.6-fold extension under the Langmuir isotherm when compared to the linear isotherm. The adsorption constants of the Freundlich and Langmuir isotherms exhibit a positive correlation with breakthrough time, while the exponent of the Freundlich isotherm and the maximal adsorption capacity in the Langmuir isotherm demonstrate a negative association with breakthrough time. This study enhances the precision of solute transport prediction and provides a more scientific assessment of clay liner performance.</p>\u0000 </div>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"48 17","pages":"4110-4121"},"PeriodicalIF":3.4,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142236179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Investigation on the Instability Mechanism of Expansive Soil Slope With Weak Interlayer Based on Strain Softening 基于应变软化的弱夹层膨胀土边坡失稳机理研究

IF 3.4 2区工程技术

International Journal for Numerical and Analytical Methods in Geomechanics Pub Date : 2024-09-17 DOI: 10.1002/nag.3834

Shuai Xu, Hanjing Jiang, Yongfu Xu, Aoxun Wang, Shunchao Qi

{"title":"Investigation on the Instability Mechanism of Expansive Soil Slope With Weak Interlayer Based on Strain Softening","authors":"Shuai Xu, Hanjing Jiang, Yongfu Xu, Aoxun Wang, Shunchao Qi","doi":"10.1002/nag.3834","DOIUrl":"10.1002/nag.3834","url":null,"abstract":"<div>\u0000 \u0000 <p>Expansive soils are widespread in the world and coincide with areas of high human activity. The main cause of deep instability of expansive soil slopes is due to their softening caused by excavation and seepage. By developing a comprehensive numerical model based on the theory of unsaturated soil, this study examines the characteristics of stress and displacement distribution of expansive soil slopes through hydraulic-mechanical coupled numerical simulation. This study analyzes the evolution patterns of slopes with excavation unloading and seepage of water storage to reveal the mechanisms of deep-seated instability of expansive soil slopes. The findings demonstrate that: The instability of expansive soil slopes begins at the foot of the slope and propagates along the interlayer, affecting the entire slope. Excavation leads to the softening of the expansive soil interlayer and the transfer of shear stress. During water storage, the weakening of the soil strength results in slope instability along the weak interlayer slip. Softening of the expansive soil interlayer facilitates the redistribution of shear forces in the slope and alters the distribution law of the plastic zone in the deep layer. Overly slowing down the slope leads to significant excavation unloading, which is detrimental to the slope's stability.</p>\u0000 </div>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"48 17","pages":"4122-4135"},"PeriodicalIF":3.4,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142236219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

An Analytical Insight Into Stability Analysis of Unsaturated Multi-Layered Slopes Subjected to Rainfall Infiltration 受降雨渗透影响的非饱和多层斜坡稳定性分析透视

IF 3.4 2区工程技术

International Journal for Numerical and Analytical Methods in Geomechanics Pub Date : 2024-09-16 DOI: 10.1002/nag.3833

Cheng Yuan, Changbing Qin, Yueling Yang, Zhibin Sun, Liang Li, Xiaoqin Lei, Siau Chen Chian

{"title":"An Analytical Insight Into Stability Analysis of Unsaturated Multi-Layered Slopes Subjected to Rainfall Infiltration","authors":"Cheng Yuan, Changbing Qin, Yueling Yang, Zhibin Sun, Liang Li, Xiaoqin Lei, Siau Chen Chian","doi":"10.1002/nag.3833","DOIUrl":"https://doi.org/10.1002/nag.3833","url":null,"abstract":"<div>\u0000 \u0000 <p>Slopes in nature usually present layered characteristics, and its stability is susceptible to rainfall events. Considering that current analytical solutions are only suited to simulate the rainfall infiltration of double-layered infinite unsaturated slopes, an analytical procedure is hence proposed in this study to tackle the consideration of multiple layers. The variable separation method and transfer matrix method are combined to derive the analytical solution of pore water pressure (PWP) for simulating rainfall infiltration in layered infinite unsaturated slopes. After having validated the proposed model and analytical solutions by comparing with existing literature and numerical simulation, the closed-form solution of PWP is incorporated into the limit equilibrium for assessing slope stability. A three-layer slope is selected as an example for further discussion. PWP distribution and factor of safety are calculated, considering the effects of saturated hydraulic conductivity and thickness of the upper layer, intensity of antecedent and subsequent rainfall, and varied soil unit weight along the depth. The slope stability subjected to rainfall effects is consistent with the variation of PWP. The proposed analytical solutions provide a simple and practical avenue for computing PWP distribution and evaluating the stability of multi-layered slopes under rainfall conditions, which can also serve as a benchmark for numerical solutions.</p>\u0000 </div>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"48 17","pages":"4291-4303"},"PeriodicalIF":3.4,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142642412","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Cover Image, Volume 48, Issue 14 封面图片，第 48 卷第 14 期

IF 3.4 2区工程技术

International Journal for Numerical and Analytical Methods in Geomechanics Pub Date : 2024-09-10 DOI: 10.1002/nag.3840

Kehao Chen, Rui Pang, Bin Xu, Xingliang Wang

引用次数: 0

Extended B-spline-based implicit material point method for saturated porous media 饱和多孔介质的基于 B 样条的扩展隐式材料点法

IF 3.4 2区工程技术

International Journal for Numerical and Analytical Methods in Geomechanics Pub Date : 2024-09-03 DOI: 10.1002/nag.3827

Yuya Yamaguchi, Shuji Moriguchi, Kenjiro Terada

{"title":"Extended B-spline-based implicit material point method for saturated porous media","authors":"Yuya Yamaguchi, Shuji Moriguchi, Kenjiro Terada","doi":"10.1002/nag.3827","DOIUrl":"10.1002/nag.3827","url":null,"abstract":"<p>The large deformation and fluidization process of a solid–fluid mixture includes significant changes to the temporal scale of the phenomena and the shape and properties of the mixed material. This paper presents an extended B-spline (EBS)-based implicit material point method (EBS-MPM) for the coupled hydromechanical analysis of saturated porous media to enhance the overall versatility of MPM in addressing such diverse phenomena. The proposed method accurately represents phenomena such as high-speed motion in both the quasi-static and dynamic states by employing a full formulation of coupled hydromechanical modeling. The weak imposition of boundary conditions based on Nitsche's method allows representing the boundary conditions independent of the relative position of the particles and computational grid. In addition, it enables dynamic changes in the boundary domain based on the deformation. The robustness of this boundary representation is reinforced using EBS basis functions, which prevent the degradation of the condition number of the system matrices regardless of the position of the boundary domain with respect to the computational grid. Furthermore, a stabilization method based on a variational multiscale method (VMS) approach is employed to provide the flexibility in choosing arbitrary basis functions for spatial discretization, facilitating the effective construction of EBS. Numerical examples including comparisons between a full formulation and a simplified formulation are presented to demonstrate the performance of the developed method under various boundary conditions and loading states across different time scales.</p>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"48 16","pages":"4057-4085"},"PeriodicalIF":3.4,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/nag.3827","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142131006","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Development of improved finite element formulations for pile group behavior analysis under cyclic loading 开发循环加载下桩群行为分析的改进型有限元公式

IF 3.4 2区工程技术

International Journal for Numerical and Analytical Methods in Geomechanics Pub Date : 2024-09-03 DOI: 10.1002/nag.3828

Jian-Hong Wan, Shui-Hua Jiang, Xue-You Li, Zhilu Chang

{"title":"Development of improved finite element formulations for pile group behavior analysis under cyclic loading","authors":"Jian-Hong Wan, Shui-Hua Jiang, Xue-You Li, Zhilu Chang","doi":"10.1002/nag.3828","DOIUrl":"10.1002/nag.3828","url":null,"abstract":"<p>The effect of cyclic loading is an essential factor leading to progressive soil strength degradation. Therefore, a comprehensive analysis of the pile-soil system behavior under cyclic loading is required to ensure the stability of pile group. There is room for improvement in the inherent constraint of the conventional numerical model in terms of approximating the soil resistance distribution along the pile by point loads at element nodes, necessitating a specific element that integrates considerations of pile group effect and cyclic loading within a unified framework. This study aims to develop a newly specific type of element for efficiently predicting nonlinear behavior within the pile-soil system, addressing simulations involving nonlinear pile-soil interaction, pile group effect, and cyclic loading. Modified element formulations based on soil stiffness matrices and soil resistance vectors specifically address pile group effect and consider parameters that influence pile behavior under cyclic lateral loading. The numerical solution procedure with Newton-Raphson iteration allows the calculation of pile responses in geometric and material nonlinear analyses. The validation of the proposed method includes several examples, comparing it with existing numerical solutions and experimental tests of single piles and pile groups under cyclic loading. These comparisons further support the consistency of the proposed method with measured data and validate its accuracy in considering group effect and cyclic loading. The parametric study illustrates the ability of the proposed method to capture cyclic loading parameters while considering the influence of the number and magnitude of load cycles, the cyclic load direction, and the installation methods.</p>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"48 17","pages":"4089-4109"},"PeriodicalIF":3.4,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142131007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Optimization-based pore network modeling approach for determination of hydraulic conductivity function of granular soils 基于优化的孔隙网络建模方法确定粒状土的导水函数

IF 3.4 2区工程技术

International Journal for Numerical and Analytical Methods in Geomechanics Pub Date : 2024-08-29 DOI: 10.1002/nag.3826

Suaiba Mufti, Arghya Das

{"title":"Optimization-based pore network modeling approach for determination of hydraulic conductivity function of granular soils","authors":"Suaiba Mufti, Arghya Das","doi":"10.1002/nag.3826","DOIUrl":"10.1002/nag.3826","url":null,"abstract":"<p>A wide range of applications of unsaturated hydraulic conductivity is well known in geotechnical, hydrological, and agricultural engineering fields. The standard prediction models for hydraulic conductivity function overlook the complexity of soil pore structure and employ a simplistic approach based on the bundle of capillary tubes. This study proposes an alternative approach employing pore network models calibrated to match soil water retention data to predict the hysteretic hydraulic conductivity function of granular soils. A novel approach to constructing a multidirectional pore network built on an irregular lattice with variable coordination numbers is presented for the realistic representation of soil voids. The geometric and topological parameters of the pore network model are optimized using the genetic algorithm, and adequate pore-scale processes (piston-like advance and corner flow during drainage and piston-like advance, pore body filling, and snap-off during imbibition) are modeled to get reasonable predictions of hysteretic hydraulic conductivity functions over the entire suction range of granular soils. Comparisons between the pore network model results, standard physically based models, and measured data for a variety of granular soils show that the proposed pore network has a superior performance over other models and compares favorably to the experimental data.</p>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"48 16","pages":"4035-4056"},"PeriodicalIF":3.4,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142101176","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Contraction and expansion of a cylindrical cavity in an elastoplastic medium: A dislocation-based approach 弹塑性介质中圆柱形空腔的收缩和膨胀：基于位错的方法

IF 3.4 2区工程技术

International Journal for Numerical and Analytical Methods in Geomechanics Pub Date : 2024-08-28 DOI: 10.1002/nag.3825

Yue Gao, Emmanuel Detournay

{"title":"Contraction and expansion of a cylindrical cavity in an elastoplastic medium: A dislocation-based approach","authors":"Yue Gao, Emmanuel Detournay","doi":"10.1002/nag.3825","DOIUrl":"10.1002/nag.3825","url":null,"abstract":"<p>The contraction or expansion of a cylindrical cavity in an elastoplastic medium is usually analyzed from a continuum based approach with a plasticity constitutive model. However, localized deformations, which are rooted in the post-failure softening response of geomaterials, are observed in the form of spiral-shaped fractures in laboratory tests. An alternative approach based on dislocation theory is introduced in this paper for modeling cavity contraction or expansion. In this model, several equally spaced spiral-shaped shear fractures initiate and propagate away from the cavity within the linearly elastic medium. The Mohr-Coulomb criterion and a dilatancy rule are imposed on the shear fractures to constrain the stresses and the displacement jumps. The direction of fracture propagation is determined by minimizing plastic dissipation. The displacement discontinuity method is used to discretize the shear and normal displacement jumps along the fracture and solve the problem numerically. The calculated crack path follows a logarithmic-like spiral, similar to the slip lines predicted by plasticity theory. The relationship between the pressure and radial displacement at the cavity boundary converge towards the classical elastoplastic solution as the number of fracture branches increases.</p>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"48 16","pages":"4014-4034"},"PeriodicalIF":3.4,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/nag.3825","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142090000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Instability of binary mixtures subjected to constant shear drained stress path: Insight from macro and micro perspective 二元混合物在恒定剪切排水应力路径下的不稳定性：从宏观和微观角度看问题

IF 3.4 2区工程技术

International Journal for Numerical and Analytical Methods in Geomechanics Pub Date : 2024-08-28 DOI: 10.1002/nag.3823

Zhouyi Yan, Yang Liu, Debin Zhao

{"title":"Instability of binary mixtures subjected to constant shear drained stress path: Insight from macro and micro perspective","authors":"Zhouyi Yan, Yang Liu, Debin Zhao","doi":"10.1002/nag.3823","DOIUrl":"10.1002/nag.3823","url":null,"abstract":"<p>Loose granular materials may also exhibit instability behaviors similar to liquefaction under drained conditions, commonly referred to as diffuse instability, which can be studied through constant shear drained (CSD) tests. So far, the research on CSD in binary mixtures is still insufficient. Therefore, a series of numerical tests using the discrete element method (DEM) were conducted on binary mixtures under CSD path. The possible model of instability is categorized into type I and type II, type I instability occurs prior to reaching the critical state line (CSL), whereas type II instability occurs after exceeding the CSL. The study analyzes the macroscopic instability behavior and the impact of fine content (FC) on macroscopic instability behavior. The numerical results show that as FC increases, the slope of the instability line (IL) increases initially and then falls in the <i>p</i>-<i>q</i> plane. In the <i>e</i>-<i>p</i> plane, the IL decreases initially and then ascends. The instability type of the binary mixtures is influenced not only by relative density but also by FC. The stability index increased first and then decreased with the increase of FC. The microscopic origin of binary mixtures instability is explored by investigating the fabric-stress relationship. The collapse of the weak contact sub-network triggers the specimen instability, while the strong contact sub-network dictates the difficulty of achieving instability. FC influences the evolution of fabric anisotropy of the strong and weak contact networks, thereby controlling the macroscopic instability behavior of binary mixtures.</p>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"48 16","pages":"3997-4013"},"PeriodicalIF":3.4,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142090353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Failure mechanism of fully grouted rock bolts subjected to pullout test: Insights from coupled FDM-DEM simulation 接受拉拔试验的全灌浆岩石螺栓的失效机理：FDM-DEM 耦合模拟的启示

IF 3.4 2区工程技术

International Journal for Numerical and Analytical Methods in Geomechanics Pub Date : 2024-08-26 DOI: 10.1002/nag.3824

Hongyan Zhao, Kang Duan, Yang Zheng, Qiangyong Zhang, Longyun Zhang, Rihua Jiang, Jinyuan Zhang

{"title":"Failure mechanism of fully grouted rock bolts subjected to pullout test: Insights from coupled FDM-DEM simulation","authors":"Hongyan Zhao, Kang Duan, Yang Zheng, Qiangyong Zhang, Longyun Zhang, Rihua Jiang, Jinyuan Zhang","doi":"10.1002/nag.3824","DOIUrl":"10.1002/nag.3824","url":null,"abstract":"<p>Fully grouted rock bolts are widely used in mining, tunneling, and pit support, and thus the study of their anchorage performance is beneficial for optimizing the anchorage system design. In this study, an FDM-DEM coupled numerical model is established to simulate the whole process of rock bolt pullout test and to investigate the failure mechanism of fully grouted rock bolts. The accuracy of the model is verified by comparison with existing laboratory test results. Virtual experiments are conducted on different models by eliminating the anchor plate, changing the layered rock strata condition, and adding bolts. The results show that the presence of an anchor plate will reduce tensile stress to restrain the rupture of surrounding rock and thus improve the strengthening effect. Due to the different bond strength and tensile strength of the soft and hard rock mediums, the layer sequence of the rock strata affects the maximum pullout force. The upper-soft and lower-hard composite rock strata (S-HCR) exhibits single-cone damage while the upper-hard and lower-soft composite rock strata (H-SCR) exhibits double-cone damage. The superposition effect of the anchor group on the stresses and displacements is the reason leading to the reduction of the maximum load-bearing capacity of the rock bolts.</p>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"48 16","pages":"3979-3996"},"PeriodicalIF":3.4,"publicationDate":"2024-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142084951","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0