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

{"title":"Safer Underground Stopes with Quantified Uncertainty: An Interpretable and Data-Driven Update to the Stability Graph","authors":"Shuai Huang,&nbsp;Jian Zhou","doi":"10.1002/nag.70373","DOIUrl":"https://doi.org/10.1002/nag.70373","url":null,"abstract":"<div>\u0000 \u0000 <p>Accurate stope stability assessment is essential for safe underground mining. This study develops an interpretable, data-driven framework to update the conventional stability graph and reduce its reliance on predefined linear boundaries. Based on 426 cases, a multilayer perceptron optimized by balancing composite motion optimization achieves a test accuracy of 90.70%. Stratified bootstrap resampling confirms stable lower bound performance, with 95% confidence intervals of [0.85, 0.95] for accuracy, [0.83, 0.95] for balanced accuracy, and [0.85, 0.95] for weighted F1 score. Monte Carlo perturbation of rock mass and geometric inputs produces only about a 1% label-flip rate, indicating robustness to moderate input uncertainty. Sensitivity and interpretability analyses identify the stability number as the dominant factor, while hydraulic radius acts as a secondary variable with strong interaction effects. Residual Kriging is then used to calibrate predicted probabilities in the stability graph, select an optimal decision threshold of 0.3, and define an uncertainty zone for ambiguous conditions. Relative to existing stable–unstable prediction boundaries, the updated graph shows stronger class separation, and external validation on two independent datasets yields conservative accuracies above 90%. The framework is mainly intended for open stoping and open-span stability assessment; application to mining methods governed by different failure mechanisms requires site-specific recalibration and validation. Overall, the study provides an interpretable and uncertainty-aware pathway for quantitative stability graph refinement.</p>\u0000 </div>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"50 13","pages":"5117-5148"},"PeriodicalIF":3.6,"publicationDate":"2026-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148704514","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":"Measuring Rate- and State-Dependent Stick-Slip Friction Parameters Under a Low-Stiffness Loading Condition","authors":"Hengtao Yang,&nbsp;Hang Lin,&nbsp;Bing Bai,&nbsp;Yan Zou","doi":"10.1002/nag.70358","DOIUrl":"10.1002/nag.70358","url":null,"abstract":"<div>\u0000 \u0000 <p>The rate‑ and state‑dependent friction (RSF) law effectively characterizes fault stick‑slip behavior, with its parameters acting as key variables controlling the mechanical response of fault surfaces. Because these parameters are highly sensitive to the stiffness of the measuring system, this study investigates a method for determining RSF parameters under low‑stiffness loading. Numerical simulations are used to analyze the relationship between characteristic features of the low‑stiffness stress–displacement curves and the friction parameters, thereby verifying the feasibility of the approach. Comparisons further reveal distinct measurement behaviors between high‑ and low‑stiffness systems. The results demonstrate that friction parameters can be reliably inverted from shear tests using a low‑stiffness machine. This method substantially reduces apparatus requirements and enables parameter extraction from the system's spontaneous stick‑slip response without an imposed velocity step, opening the possibility for continuous, real‑time monitoring of friction evolution during loading.</p>\u0000 </div>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"50 13","pages":"4994-5008"},"PeriodicalIF":3.6,"publicationDate":"2026-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148288321","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":"Numerical Simulation of the Influence of Skeleton Particle Roughness on the Mechanical Behavior of Cemented Soil-Rock Mixtures Under Cyclic Loading","authors":"Fengming Qian,&nbsp;Chong Shi,&nbsp;Liang Liu,&nbsp;Xuan Tang","doi":"10.1002/nag.70372","DOIUrl":"10.1002/nag.70372","url":null,"abstract":"<div>\u0000 \u0000 <p>The roughness of skeleton particles is a critical factor influencing the macroscopic mechanical properties of cemented soil-rock mixtures (CSRM). Under cyclic loading, the quantitative effect of roughness on macroscopic material performance is challenging to ascertain. This study employed spherical harmonic reconstruction to generate particle models that consider realistic surface morphology. Three-dimensional discrete element method (DEM) numerical specimens reflecting different roughness levels were established. Through cyclic shear numerical tests under varying roughness conditions, the influence of roughness on the macroscopic hysteresis characteristics and stress-strain response of the material was quantitatively analyzed. Furthermore, the underlying mechanism was elucidated by examining mesoscopic features, including displacement fields, and the magnitude and spatial distribution of contact forces. The results indicate that as roughness increases, the connectivity of the force chain network is enhanced, and the constraining effect of skeleton particles on the displacement of surrounding soil is improved, effectively suppressing interparticle sliding and rotation. Macroscopically, this manifests as a reduction in hysteresis loop area and an enhanced deformation resistance under cyclic loading. Additionally, increasing the loading rate further strengthens the peak deviatoric strength of the material and inhibits crack propagation. The findings provide a reference for evaluating the mechanical performance of CSRM under cyclic loading.</p>\u0000 </div>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"50 13","pages":"4967-4980"},"PeriodicalIF":3.6,"publicationDate":"2026-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148288324","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":"A Novel Framework for Reliability Analysis of Rainfall-Induced Slopes Failure Based on Site-Specific Data","authors":"Rui Yang,&nbsp;Yanan Meng,&nbsp;Guoqing Cai,&nbsp;Jinsong Huang","doi":"10.1002/nag.70370","DOIUrl":"https://doi.org/10.1002/nag.70370","url":null,"abstract":"<div>\u0000 \u0000 <p>Rainfall-induced slope failure is governed by complex multivariate interactions and inherent spatial variability of soil properties. However, conventional Gaussian-based reliability models fail to capture the nonlinear dependencies between hydraulic and mechanical parameters and cannot fully utilize limited site-specific data. This paper develops a Copula-based conditional random field (Copula-CRF) framework that explicitly incorporates multivariate non-Gaussian dependencies and maximizes the use of site-specific data in probabilistic slope stability evaluation. The framework first identifies optimal Copula structures for multivariate parameters based on site-specific data and then embeds the identified dependence models into a conditional random field to generate spatially correlated realizations constrained on both hydraulic and mechanical observations. A representative slope case exhibiting failure is analyzed to evaluate the performance of the proposed approach. The Copula-URF approach yields a failure probability of 0.22, whereas the Copula-CRF approach yields 0.911, accompanied by a reduction in standard deviation from 0.207 to 0.023. The results indicate that the Copula-CRF framework provides more realistic reliability estimates than Copula-URF approaches by fully utilizing available site-specific data. The performance of the proposed framework is evaluated under varying parameter uncertainties, spatial correlations, rainfall patterns, and site investigation schemes, confirming the robustness and applicability of the approach. Applications of the proposed Copula-CRF framework demonstrate that it can reliably evaluate the stability of rainfall-induced slopes with site-specific data. The method also provides a general reference for reliability analysis and risk-informed decision-making in geotechnical engineering.</p>\u0000 </div>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"50 13","pages":"5213-5229"},"PeriodicalIF":3.6,"publicationDate":"2026-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148704451","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":"Overshooting of Hypoplastic Models With Intergranular Strain: Manifestation, Implications and Remedy","authors":"Jan Machaček,&nbsp;Merita Tafili,&nbsp;Carlos Grandas Tavera","doi":"10.1002/nag.70375","DOIUrl":"https://doi.org/10.1002/nag.70375","url":null,"abstract":"<p>Intergranular strain extensions of hypoplasticity (IGS, ISA, GIS) are widely used to model small-strain and cyclic soil behaviour. However, recent studies and our own simulations reveal that these models can exhibit stress overshooting not only under repeated small loading cycles but also during monotonic loading. This manifests as an unphysical accumulation of deviatoric stress and mobilised friction angles exceeding <span></span><math>\u0000 <semantics>\u0000 <msup>\u0000 <mn>60</mn>\u0000 <mo>∘</mo>\u0000 </msup>\u0000 <annotation>$60^circ$</annotation>\u0000 </semantics></math>, leading to overpredicted shear strength and stiffness. Of the three inspected extensions, IGS and ISA are the most susceptible to overshooting. While GIS mitigates overshooting under deviatoric loading, it persists during oedometric unloading-reloading. The cause lies in the constitutive structure of intergranular strain frameworks: when the mobilisation variable satisfies <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>ρ</mi>\u0000 <mo>&lt;</mo>\u0000 <mn>1</mn>\u0000 </mrow>\u0000 <annotation>$rho &lt;1$</annotation>\u0000 </semantics></math>, the effective elastic strain range becomes too large relative to the prevailing stress state, allowing stress accumulation with insufficient plastic dissipation. To regularise this behaviour while retaining the hypoplastic backbone, a two-step projection approach is proposed that activates only upon violation: (i) a deviatoric projection onto an auxiliary Matsuoka-Nakai surface with a state-dependent cut-off angle; and (ii) an isotropic projection that limits the mean effective stress to a state-dependent bounding pressure consistent with hypoplastic barotropy. Validation across four benchmark problems, including triaxial compression tests with monotonic loading and cyclic reloading, oedometric compression with unloading/reloading cycles and a laterally loaded pile, demonstrates that the projection is non-intrusive when the stress state remains admissible, and effectively regularises overshooting when it does not. The approach improves model robustness and physical consistency in simulations involving small-strain cycling or expanding plastic zones.</p>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"50 13","pages":"5068-5091"},"PeriodicalIF":3.6,"publicationDate":"2026-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/nag.70375","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148704509","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":"Analysis on Bearing Mechanism of T-Shaped Pressure Cast-Situ-Solidified Soil Pile With Spray Expanded Frustum","authors":"Sheng-shi Qiao,&nbsp;Qian-qing Zhang,&nbsp;Jing-guang Cao,&nbsp;Jing-hang Liu,&nbsp;Shu-jian Wang,&nbsp;Wei Cui","doi":"10.1002/nag.70380","DOIUrl":"https://doi.org/10.1002/nag.70380","url":null,"abstract":"<div>\u0000 \u0000 <p>T-shaped pressure cast-situ-solidified soil pile with a spray-expanded frustum (T-PSPSF) is composed of fluidized solidified soil, and features distinct upper and lower pile sections with varying diameters, an expanded body with double-frustum (EBDF), and ribbed plates. T-PSPSF exhibits superior performance including high bearing capacity, enhanced construction productivity, and notable economic and environmental benefits. Based on the laboratory test results, the mechanical parameters of the pile are clarified. The geometric configuration of the pile was determined through field tests. For practical purposes, the diameter prediction method of EBDF is proposed. Additionally, numerical simulations were conducted with varying diameters, heights, and positions of EBDF, as well as different ratios of upper pile diameter to lower pile diameter, to determine the optimal pile structure. The load-sharing ratio of the EBDF to the total pile head load exceeds 50%. Considering both the bearing characteristics and economic efficiency of the T-PSPSF, the optimal diameter of EBDF is adopted as 1.4<i>D</i>, the optimal length is 1.0<i>D</i>, the optimal position can be adopted between 5<i>D</i> and 7<i>D</i> above the pile head, and the optimal ratio of upper pile diameter to lower pile diameter is taken as 0.5.</p>\u0000 </div>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"50 13","pages":"5171-5184"},"PeriodicalIF":3.6,"publicationDate":"2026-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148704304","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":"A Novel Two-Dimensional Axisymmetric Thermo-Hydro-Mechanical Coupled Model for Subsea Pipeline-Soil System Considering Imperfect Interfacial Thermal Contact","authors":"Kejie Tang,&nbsp;Tianning Zhang,&nbsp;Linlong Mu,&nbsp;Minjie Wen,&nbsp;Yuan Tu","doi":"10.1002/nag.70376","DOIUrl":"10.1002/nag.70376","url":null,"abstract":"<div>\u0000 \u0000 <p>Subsea oil pipelines typically operate under high-temperature and high-pressure conditions, where imperfect contact at the pipeline-soil interface hinders heat transfer. However, existing calculation models neglect the effect of interfacial thermal resistance, leading to inaccurate predictions of pipeline-soil interactions. This article establishes a two-dimensional (2D) axisymmetric thermo-hydro-mechanical (THM) coupling model for deeply buried subsea pipeline and saturated soil based on single-phase thermoelastic theory and saturated porous thermoelastic theory, respectively. The general thermal contact model is introduced to characterize the interfacial thermal resistance effects. A semi-analytical solution for pipeline-soil interaction is obtained through Laplace transforms and separation of variables. The differences in THM coupled response between pipeline-soil system under various thermal contact models are examined, and the influence of thermal expansion coefficients on pipeline-soil interaction is parametrically investigated under the general thermal contact model. The results indicate that the general thermal contact model can describes the THM coupling characteristics of the pipeline-soil interaction more realistically; the interfacial thermal resistance effect causes a significant radial temperature gradient at the interface within the pipeline-soil system, slightly increases the axial temperature difference inside the pipeline, affects the influence of thermal expansion coefficient on the pipeline-soil interaction, and reduces the deformation compatibility; the influence of the interfacial thermal resistance effect becomes more pronounced as thermal expansion coefficient increases. The deformation compatibility of the pipeline-soil system decreases as the thermal resistance coefficient and partition thermal contact coefficient increase.</p>\u0000 </div>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"50 13","pages":"5009-5038"},"PeriodicalIF":3.6,"publicationDate":"2026-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148288322","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":"An Operational Matrix Approach Using Chebyshev Polynomials for Solving Generalized Caputo Fractal-Fractional Differential Equations","authors":"Sumit Kumar,&nbsp;Sunil Kumar,&nbsp;Shaher Momani","doi":"10.1002/nag.70379","DOIUrl":"https://doi.org/10.1002/nag.70379","url":null,"abstract":"<div>\u0000 \u0000 <p>This study introduces an approach relying on the application of an operational matrix based on shifted Chebyshev polynomials for numerically addressing fractal-fractional (FF) linear and nonlinear differential equations, as well as systems of equations, utilizing the generalized fractional derivative of Caputo type. The proposed method transforms the generalized Caputo-type FF derivatives transformed into a system of algebraic equations, enabling the determination of unknown solutions. Theoretical analysis was conducted to establish convergence criteria and derive error bounds for the method. The approach was validated through quantitative analysis across various scenarios and benchmarked against established techniques to affirm its precision and computational effectiveness. Additionally, the method was applied to the SIRD (Susceptible-Infected-Recovered-Deceased) mathematical model with a FF operator, employing the spectral collocation method to demonstrate the effectiveness of the proposed numerical approach in handling FF derivatives.</p></div>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"50 13","pages":"5149-5170"},"PeriodicalIF":3.6,"publicationDate":"2026-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148704303","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":"Reliability Analysis of Ring Footings Using Random Field Finite Element Limit Analysis and Stacked Machine Learning Surrogates","authors":"Tran Vu-Hoang,&nbsp;Tan Nguyen,&nbsp;Jim Shiau,&nbsp;Duy Ly-Khuong,&nbsp;Hung-Thinh Pham-Tran","doi":"10.1002/nag.70378","DOIUrl":"https://doi.org/10.1002/nag.70378","url":null,"abstract":"<div>\u0000 \u0000 <p>Reliable design of shallow foundations is critical for offshore and coastal infrastructure such as towers, tanks, and wind energy structures. This study presents a framework that combines finite element limit analysis (FELA), random field theory, and ensemble machine learning to evaluate the probability of failure (<i>PF</i>) of ring footings in spatially variable soils. Random fields of soil friction angle (<i>ϕ</i>) and unit weight (<i>γ</i>) are modelled with lognormal distributions and exponential autocorrelation, while Monte Carlo simulations with FELA generate a comprehensive reliability dataset under varying coefficients of variation, correlation lengths, and safety factors. Several surrogates, including support vector regression, multivariate adaptive regression splines, artificial neural networks, and Kolmogorov—Arnold networks, are benchmarked. A stacked model integrating KAN and ANN with a support vector meta-learner achieves superior accuracy (<i>R</i>² = 0.993) and consistent calibration. Parametric analyses show that PF is mainly controlled by safety factor and soil variability, while correlation length and ring slenderness exert secondary influences. The framework further provides reliability design charts that incorporate geotechnical variability and geometric effects. These results highlight the efficiency of surrogate-assisted random field FELA for reliability-based design, offering offshore engineers practical tools to assess foundation safety under uncertainty.</p>\u0000 </div>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"50 13","pages":"5092-5116"},"PeriodicalIF":3.6,"publicationDate":"2026-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148704511","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":"Nonlocal Analysis of Rayleigh Wave Propagation in Layered Media With Interface Imperfections and Surface Irregularities","authors":"Sushmita Mandal,&nbsp;Santimoy Kundu","doi":"10.1002/nag.70369","DOIUrl":"10.1002/nag.70369","url":null,"abstract":"<div>\u0000 \u0000 <p>This study focuses on the propagation of Rayleigh-type waves in a sandy layer lying over a weakly orthotropic half-space based on the principles of nonlocal elasticity theory. Both perfect and imperfect mechanical bonding conditions at the interface are examined. The governing second-order hyperbolic differential equations are solved analytically using the method of separation of variables to obtain displacement fields in closed form. The frequency equation is formulated by setting the determinant of the system of equations to zero for different interfacial conditions. Numerical evaluation of the resulting dispersion relation is performed, and the influence of parameters such as layer thickness, phase velocity, corrugation amplitude, nonlocal parameter, and imperfection parameter is studied in detail. Simulated results using Mathematica provide graphical illustrations of the variation in wave number and phase velocity for different physical scenarios. The novelty of the present study lies in the combined consideration of nonlocal elasticity, granular behavior, orthotropy, and corrugated geometry within a single analytical framework. The results reveal the distinct and sometimes opposite roles of layer and substrate nonlocality on wave dispersion.</p>\u0000 </div>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"50 12","pages":"4932-4948"},"PeriodicalIF":3.6,"publicationDate":"2026-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148288325","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}