International Journal for Numerical and Analytical Methods in Geomechanics最新文献

{"title":"Hydro-mechanically coupled CEL analyses with effective contact stresses","authors":"Patrick Staubach","doi":"10.1002/nag.3725","DOIUrl":"10.1002/nag.3725","url":null,"abstract":"<p>The coupled Eulerian–Lagrangian (CEL) method implemented in Abaqus is an established tool for modelling large deformations in numerical geomechanics. As shown in previous work, it can be extended to a hydro-mechanically coupled scheme by exploiting the similarity of the heat balance equation to the mass balance equation of fluids. However, the distinction between effective and total contact stresses has not been possible in this approach, which hinders its application to problems with interface friction as frictional stresses are calculated based on total normal contact stress. An approach to circumvent this problem is presented in this work. Its relevance is demonstrated by the simulation of vibratory pile driving model tests in water-saturated sand. The implementation by means of user-subroutines is available and works for any total-stress analysis.</p>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/nag.3725","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140173226","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}

{"title":"Multi-porous extension of anisotropic poroelasticity: Consolidation and related coefficients","authors":"Filip P. Adamus,&nbsp;David Healy,&nbsp;Philip G. Meredith,&nbsp;Thomas M. Mitchell,&nbsp;Ashley Stanton-Yonge","doi":"10.1002/nag.3727","DOIUrl":"10.1002/nag.3727","url":null,"abstract":"<p>We propose the generalization of the anisotropic poroelasticity theory. At a large scale, a medium is viewed as quasi-static, which is the original assumption of Biot. At a smaller scale, we distinguish different sets of pores or fractures that are characterized by various fluid pressures, which is the original poroelastic extension of Aifantis. In consequence, both instantaneous and time-dependent deformation lead to fluid content variations that are different in each set. We present the equations for such phenomena, where the anisotropic properties of both the solid matrix and pore sets are assumed. Novel poroelastic coefficients that relate solid and fluid phases in our extension are proposed, and their physical meaning is determined. To demonstrate the utility of our equations and emphasize the meaning of new coefficients, we perform numerical simulations of a triple-porosity consolidation. These simulations reveal positive pore pressure transients in the drained behaviour of weakly connected pore sets, and these may result in the mechanical weakening of the material.</p>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/nag.3727","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140162233","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}

{"title":"Multi-porous extension of anisotropic poroelasticity: Linkage with micromechanics","authors":"Filip P. Adamus,&nbsp;David Healy,&nbsp;Philip G. Meredith,&nbsp;Thomas M. Mitchell","doi":"10.1002/nag.3722","DOIUrl":"10.1002/nag.3722","url":null,"abstract":"<p>We attempt to formalise the relationship between the poroelasticity theory and the effective medium theory of micromechanics. The assumptions of these two approaches vary, but both can be linked by considering the undrained response of a material; and that is the main focus of the paper. To analyse the linkage between poroelasticity and micromechanics, we do not limit ourselves to the original theory of Biot. Instead, we consider a multi-porous extension of anisotropic poroelasticity, where pore fluid pressure may vary within the bulk medium of interest. As a consequence, any inhomogeneities in the material are not necessarily interconnected; instead, they may form isolated pore sets that are described by different poroelastic parameters and fluid pressures. We attempt to incorporate the effective methods inside Biot-like theory and investigate the poroelastic response of various microstructures. We show the cases where such implementation is valid and the others that appear to be questionable. During micromechanical analysis, we derive a particular case of cylindrical transverse isotropy—commonly assumed in conventional laboratory triaxial tests—where the symmetry is induced by sets of aligned cracks.</p>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/nag.3722","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140162230","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}

{"title":"A MPM Lagrangian-Eulerian hydrocode for simulating buried explosions in transversely isotropic geomaterials","authors":"Mian Xiao,&nbsp;WaiChing Sun","doi":"10.1002/nag.3717","DOIUrl":"10.1002/nag.3717","url":null,"abstract":"<p>Shock waves in geological materials are characterized by a sudden release of rapidly expanding gas, liquid, and solid particles. These shock waves may occur due to explosive volcanic eruptions or be artificially triggered. In fact, underground explosions have often been used as an engineering solution for large-scale excavation, stimulating oil and gas recovery, creating cavities for underground waste storage, and even extinguishing gas field fires. As such, hydrocodes capable of simulating the rapid and significant deformation under extreme conditions can be a valuable tool for ensuring the safety of the explosions. Nevertheless, as most of the hydrocodes are often formulated in an Eulerian grid, this setting makes it non-trivial to track the deformation configuration of the materials without a level set. The objective of this paper is to propose the use of the material point method equipped with appropriate equation of state (EOS) models as a hydrocode suitable to simulate underground explosions of transverse isotropic geomaterials. To capture the anisotropic effect of the common layered soil deposits, we introduce a new MPM hydrocode where an anisotropic version of the Mie-Gruneisen EOS is coupled with a frictional Drucker-Prager plasticity model to replicate the high-strain-rate constitutive responses of soil. By leveraging the Lagrangian nature of material points to capture the historical dependence and the Eulerian calculation of internal force, the resultant model is capable of simulating the rapid evolution of geometry of the soil as well as the high-strain-rate soil mechanics of anisotropic materials.</p>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140135584","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}

{"title":"Analytical solution for buried pipeline deformation induced by normal and reverse fault considering structural joint influence","authors":"Zhiguo Zhang,&nbsp;Jiawei Feng,&nbsp;Zhengguo Zhu,&nbsp;Qihua Zhao,&nbsp;Yutao Pan","doi":"10.1002/nag.3724","DOIUrl":"10.1002/nag.3724","url":null,"abstract":"<p>Previous studies take less account of analytical solution analysis for buried pipeline under the action of active fault. Furthermore, current theoretical studies of fault-pipeline interactions generally treat the structure as continuous pipeline, with less attention given to the effect of joints. This paper provides an analytical method to estimate the deformation and internal force of jointed pipelines under normal and reverse fault. By introducing the simplified soil deformation model and error function, the soil greenfield deformation curves under the influence of normal and reverse fault are obtained. Considering the interaction between the pipeline structure and the disturbed soil, the two-parameter Pasternak foundation model is adopted to analyze the forces on pipeline infinitesimal elements. Then, the mechanical response of the jointed pipeline structure due to the fault additional load is solved by finite difference method. The accuracy of the presented analytical solution is verified by comparisons with observed data of model test and 3D numerical simulation results. Finally, the parametric analyses are performed to estimate the influence for the characteristics of the foundation, fault and joint, including subgrade shear stiffness, subgrade reaction coefficient, fault dip, joint rotational stiffness, joint spacing, and intersection of fault and pipeline.</p>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140117882","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}

{"title":"Revisiting the face stability of rock tunnels in the Hoek–Brown strength criterion with tension cutoff","authors":"Junhao Zhong,&nbsp;Siau Chen Chian,&nbsp;Hui Chen,&nbsp;Chuantan Hou,&nbsp;Xiaoli Yang","doi":"10.1002/nag.3723","DOIUrl":"10.1002/nag.3723","url":null,"abstract":"<p>In this work, the three-dimensional stability of deep tunnel faces is evaluated in rock masses characterized by the generalized Hoek–Brown (H–B) criterion from the perspective of the limit analysis theorem. Considering that underground engineering is gradually developing towards larger burial depths and larger sizes, and the tensile strength of rocks is usually overestimated, the concept of tension cutoff (T-C) is introduced to substitute the parabolic form of the H–B envelope in the tensile region with a circular arc. The multitangent technique is used to piecewise approximate the H–B envelope, instead of the conventional linear substitution, accounting for the nonlinear dependence of the shear strength on the pressure. Meanwhile, the earthquake loading is considered by the classic pseudostatic method. The tunnel face stability is measured by a stability number, which is calculated based on a newly developed multicone failure mechanism. Parameter studies indicate that the T-C has almost no impact on the critical support pressure, while has a significant effect on the critical stability number, especially in the presence of earthquakes. Nearly all stress points back-calculated from the rupture angles fall within the T-C region, except for the first stress point associated with the first segment. Interestingly, the influence of the geological strength index (GSI) on the face stability is inverse to that of <i>m</i>_i due to the brittleness of rocks. Moreover, the critical stability number is not sensitive to <i>m</i>_i, but sensitive with the introduction of earthquake loadings.</p>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140097119","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}

{"title":"Cover Image, Volume 48, Issue 5","authors":"Jiahao Xie,&nbsp;Minjie Wen,&nbsp;Yuan Tu,&nbsp;Dazhi Wu,&nbsp;Kaifu Liu,&nbsp;Kejie Tang","doi":"10.1002/nag.3726","DOIUrl":"10.1002/nag.3726","url":null,"abstract":"<p>The cover image is based on the Research Article <i>Thermal consolidation of layered saturated soil under time-dependent loadings and heating considering interfacial flow contact resistance effect</i> by Jiahao Xie et al., https://doi.org/10.1002/nag.3677.\u0000\u0000 <figure>\u0000 <div><picture>\u0000 <source></source></picture><p></p>\u0000 </div>\u0000 </figure></p>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/nag.3726","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140057915","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}

{"title":"Impact of soft minerals on crack propagation in crystalline rocks under uniaxial compression: A grain-based numerical investigation","authors":"Yu Zhou,&nbsp;Wenjun Lv,&nbsp;Bo Li,&nbsp;Qinyuan Liang","doi":"10.1002/nag.3718","DOIUrl":"10.1002/nag.3718","url":null,"abstract":"<p>Varying external conditions in the metallogenetic process of crystalline rocks contribute to the complex mineral and textural characteristics, rendering the mechanical properties highly heterogeneous at the mineral scale. This research focused on the influences of minerals with relatively low strength and stiffness (soft minerals) in crystalline rocks on their cracking behavior. A particle-based discrete element method (DEM) was first employed to establish random grain-based models (GBM) of crystalline rocks containing soft minerals with different contents, strengths, and stiffnesses. On this basis, responses of the mechanical properties and crack propagation to these parameters were systematically investigated and an optimized micro-parameter calibration method for real CT (computed-tomography) -based GBM was then proposed considering the characteristics of soft minerals. The results demonstrate that with the decrease of the strength of soft mica, the intragranular cracks are prone to initiate and propagate inside the soft minerals and lead to the final crack coalescence. The decrease in the stiffness of soft minerals enhances their controlling effects on the cracking propagation. Based on the CT-based granite model, it was found that a heterogeneous stress field is produced due to the spatial distribution of the soft (mica) and hard (quartz and feldspar) minerals, and the mica minerals tend to terminate cracks or force cracks to deflect or bypass individual grains during crack propagation. This study sheds light on the damage and failure processes of crystalline rocks with contrast mineral components.</p>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140043550","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}

{"title":"The consolidation behavior of layered fractional viscoelastic soils considering groundwater","authors":"Zhi Yong Ai,&nbsp;Zi Kun Ye,&nbsp;Ming Jing Jiang,&nbsp;Qing Song Lu","doi":"10.1002/nag.3721","DOIUrl":"10.1002/nag.3721","url":null,"abstract":"<p>This paper investigates the consolidation behavior of multi-layered viscoelastic soils considering groundwater. First, the fractional Merchant viscoelastic model is introduced to describe the behavior of multi-layered viscoelastic soils considering groundwater. Later, the governing equations are extended to a viscoelastic medium by virtue of the elastic-viscoelastic corresponding principle in the Laplace–Hankel domain. According to the extended precise integration method, the soil layer is divided into a series of layer units. Then the relationship between general stress vector and general displacement vector on the top and bottom planes is established. Every two adjacent layer units are combined into one layer in each computational iteration. The solutions in the Laplace–Hankel domain are obtained by considering the boundary conditions, and numerical inversion is performed to obtain the solutions in the physical domain. The practicability of the present method is assessed by comparing the numerical results with those in the existing literature and done by ABAQUS. Finally, the effects of groundwater table, properties of the soils above groundwater table, load depth, viscoelastic parameters, and soil stratification are investigated.</p>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140043558","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}

{"title":"Interpreting correlations in stress-dependent permeability, porosity, and compressibility of rocks: A viewpoint from finite strain theory","authors":"Luyu Wang,&nbsp;Yanjun Zhang","doi":"10.1002/nag.3720","DOIUrl":"10.1002/nag.3720","url":null,"abstract":"<p>Characteristics of stress-dependent properties of rocks are commonly described by empirical laws. It is crucial to establish a universal law that connects rock properties with stress. The present study focuses on exploring the correlations among permeability, porosity, and compressibility observed in experiments. To achieve this, we propose a novel finite strain-based dual-component (FS-DC) model, grounded in the finite strain theory within the framework of continuum mechanics. The FS-DC model decomposes the original problem into the rock matrix and micro-pores/cracks components. The deformation gradient tensor is utilized to derive the constitutive relations. One of the novelties is that the stress-dependent variables are calculated in the current configuration, in contrast to the reference configuration used in small deformation theory. The model has only a few number of parameters, each with specific physical interpretations. It can be reduced to existing models with appropriate simplifications. Then, model performance is examined against experimental data, including permeability, porosity, compressibility, volumetric strain and specific storage. It proves that the variations of these properties are effectively described by the proposed model. Further analysis reveals the effect of pores/cracks parameters. The validity of the FS-DC model is examined across a broad range of pressures. The results show that rock properties at high confining pressures (<span></span><math>\u0000 <semantics>\u0000 <mo>&gt;</mo>\u0000 <annotation>$&amp;gt;$</annotation>\u0000 </semantics></math>300 MPa) differ from those observed under relatively low pressures (<span></span><math>\u0000 <semantics>\u0000 <mo>&lt;</mo>\u0000 <annotation>$&amp;lt;$</annotation>\u0000 </semantics></math>200 MPa). This disparity can be attributed to inelastic behaviors of micro-structure, wherein the rock skeleton undergoes permanent deformation and breakage.</p>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/nag.3720","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140016502","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}