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

{"title":"Semi‐analytical Solution of a Shallow Buried Lined Tunnel Under Full‐Slip Contact Condition","authors":"Hui Cai, Hongliang Liu, Xin Gao, Xinbo Jiang, Wenfeng Tu","doi":"10.1002/nag.3970","DOIUrl":"https://doi.org/10.1002/nag.3970","url":null,"abstract":"This paper presents a semi‐analytical method for the stress and displacement of a shallow buried lined tunnel based on the complex variable method under the full‐slip contact condition, that is, along the interface between the surrounding rock/soil mass and lining, the radial stresses and radial displacements are continuous, and the shear stresses are equal to zero. In the presented solution, the interaction between the surrounding rock/soil mass and lining, as well as the self‐weight of rock/soil mass are considered. The equations based on the boundary conditions and continuity conditions are put forward in this paper. A comparison of the stresses and displacements obtained by the analytical solution and ANSYS software shows a good agreement between the two solutions. In addition, the results also satisfied the stress boundary condition, stress continuity condition, and displacement continuity condition. A parametric study was conducted to investigate the influence of the key parameters on Young's modulus and buried depth. Finally, the results of two extreme boundary contact conditions cases, full‐slip and no‐slip contact conditions, were compared with each other to discuss the effect of the lining and the difference between the two boundary contact conditions.","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"201 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143661410","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":"Correlation Characterization Method for Thermal Parameters of Frozen Soil Under Incomplete Probability Information","authors":"Jiazeng Cao, Tao Wang, Yonglin Feng, Jin Wu, Zhiyang Wang, Guoqing Zhou","doi":"10.1002/nag.3966","DOIUrl":"https://doi.org/10.1002/nag.3966","url":null,"abstract":"In the construction process of the artificial ground freezing (AGF), the utilization of the temperature field to determine the freezing time is crucial for the safe construction. While the thermal parameter is the core parameter of the temperature field calculation. How to obtain the joint probability distribution of thermal parameters of frozen soil under limited test data is essential to improve the accuracy of the stochastic temperature field and guide safe construction. In this study, based on the sample of frozen soil in Mengtie railway station of Anhui metro line, the statistical characteristics of the thermal conductivity, volumetric heat capacity, and thermal conductivity at various temperatures were obtained. Then multidimensional Gaussian copula models at different temperatures were constructed using three construction methods to characterize the correlations among the thermal parameters. Additionally, the correlation coefficients under three methods were simulated using Monte Carlo simulation (MCS) and the fitting errors were calculated. Finally, the Sobol indices of thermal parameters were calculated by a simple one‐dimensional heat conduction model. The results show that the frozen soil thermal parameters have obvious correlation variability at various temperatures. The Pearson method presents the most favorable fitting capability in the construction of the joint distribution model of frozen soil thermal variables. The error of the simulation results is the smallest when the construction method and correlation coefficient are identical. The Sobol indices calculated by different methods have significant differences, with the Sobol indices using the Kendall method exhibiting a higher sensitivity to the nonlinearity of the parameters.","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"4 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143608346","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":"Prediction of Unconfined Compressive Strength of Cemented Tailings Backfill Containing Coarse Aggregate Using a Hybrid Model Based on Extreme Gradient Boosting","authors":"Jinping Guo, Zechen Li, Xiaolin Wang, Qinghua Gu, Ming Zhang, Haiqiang Jiang, Caiwu Lu","doi":"10.1002/nag.3972","DOIUrl":"https://doi.org/10.1002/nag.3972","url":null,"abstract":"The utilization of cemented tailings backfill (CTB) presents distinct advantages in managing tailings and underground mining voids, occasionally incorporating coarse aggregate. In this study, the particle swarm optimization (PSO) algorithm was employed to optimize the extreme gradient boosting (XGBoost) model for predicting the unconfined compressive strength (UCS) of CTB containing coarse aggregate (CTBCA). Additionally, feature importance was compared and analyzed. The findings indicate that the PSO‐XGBoost model exhibits high accuracy on the test set, with a root mean square error (RMSE) of 0.091, a mean square error (MSE) of 0.008, and a coefficient of determination (<jats:italic>R</jats:italic><jats:sup>2</jats:sup>) of 0.999. The predicted values demonstrate a high degree of consistency with the actual results, exhibiting minimal errors that follow a normal distribution. The feature importance analysis reveals that the cement‐sand ratio holds the highest importance score and exerts a significant influence on the UCS prediction. In descending order of impact, the next most significant factors are curing age, slurry concentration, and the coarse aggregate ratio. The proposed PSO‐XGBoost model effectively reduces the UCS measurement cycle while maintaining prediction accuracy. Thus, this model has the potential to provide a fast and efficient method for predicting the UCS of CTBCA.","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"49 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143607953","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 Debris Flow Impact on Pier With Different Cross‐Sectional Shapes Based on Coupled CFD‐DEM","authors":"Zhuhong Wang, Hang Zhou, Yunzhou Li, Zengliang Wang","doi":"10.1002/nag.3971","DOIUrl":"https://doi.org/10.1002/nag.3971","url":null,"abstract":"Concrete piers located in steep mountainous regions are highly susceptible to damage from debris flows. Existing studies often oversimplify debris flows as particle flows or equivalent fluids, neglecting their multiphase characteristics. In this paper, a three‐dimensional numerical model of debris flow‐bridge piers interaction is established based on the coupled CFD‐DEM approach. The Hertz–Mindlin (no‐slip) model and the Navier–Stokes equations are employed to describe the behavior of particle contacts and the fluid phase, respectively. An interface program compiled using user‐defined functions (UDFs) facilitates the transfer of information (drag, buoyancy, and viscous forces) between the fluid and particles. The accuracy of the model is validated by the simulation results of single‐particle settlement and underwater granular collapse. This study conducts a detailed investigation into the interaction mechanisms between the debris flow—bridge piers, considering the cross‐sectional shape of the piers and the solid volume fraction. It has been discovered that the shape of the bridge piers significantly influences the behavior of debris flows and the separation points. A power function effectively describes the relationship between the solid volume fraction and the peak impact force coefficient, <jats:italic>C</jats:italic><jats:sub>d</jats:sub>. Simplifying debris flows to dry granular flows or equivalent fluids may lead to an underestimation of the impact pressure.","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"14 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143607951","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":"Multiphase and Multiphysics Modelling of Rainfall Induced Failure in an Experimental Hillslope","authors":"Maria Lazari, Matteo Camporese, Lorenzo Sanavia","doi":"10.1002/nag.3963","DOIUrl":"https://doi.org/10.1002/nag.3963","url":null,"abstract":"Annual precipitation and its intensity have increased worldwide since the start of the 20th century and represent two weather and climate change indicators related to rainfall‐induced landslides. Although these landslides can occur in a very short time, the hydro‐mechanical conditions that precede them can take several hours or days to develop. In this context, understanding the mechanisms of rainfall‐induced landslides and their numerical modelling is topical for reducing risks to human life, facilities and infrastructure and economic loss.In this work, a large‐scale experimental hillslope subjected to a controlled rainfall is studied numerically. Sensors and optical fibres were placed in the slope to monitor water pressure and moisture content in the failure layer, as well as axial strain and temperature in the failure surface. The outflow at the toe of the slope was also measured. The experimental hillslope is modelled as a fully coupled variably saturated hydro‐thermo‐mechanical problem in dynamics. A general geometrically linear finite element model based on Hybrid Mixture Theory and enhanced with Taylor‐Hood finite elements is used. The soil response is modelled with the Bolzon–Schrefler model for non‐isothermal variably saturated soils. The failure mechanism is further assessed using the global second‐order work criterion. The comparison between the experimental and numerical results is analysed using the KGE indicator, showing that the model is capable to correctly reproduce both the hydrological dynamics leading to failure and the strain along the failure surface. The global second‐order work criterion proved to predict the proneness to failure.","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"60 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143599378","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":"Transient Analysis of a Poroelastic Soil Layer Due to Horizontal Movement of a Rigid Disk Attached on the Layer With a Relaxed Boundary Condition","authors":"Xinjun Zou, Zijian Yang, Minhua Zhou, Lanyi Huang","doi":"10.1002/nag.3967","DOIUrl":"https://doi.org/10.1002/nag.3967","url":null,"abstract":"This paper is concerned with the study of a poroelastic soil layer under impulsive horizontal loading. Building upon Biot's general theory of poroelasticity, a comprehensive set of governing equations addressing three‐dimensional transient wave propagation problem are established. Explicit general solutions for displacements and pore‐pressures are derived by employing a sophisticated mathematical approach, incorporating decoupling transformation, Fourier series expansion, and Laplace–Hankel integral transform techniques. Subsequently, physical‐domain components are numerically obtained by an enhanced Durbin method coupled with inverse Hankel transform. Comparisons the existing transient solutions for the ideal elastic half‐space are made to validate the proposed formulations' reliability and precision. Through representative analyses for time‐domain results, it is illustrated to study the influence of the soil thickness and types of loading pulse on the transient dynamic response of finite‐thickness poroelastic soil layers. The results in comparative analysis show that the magnitudes of the horizontal displacement and pore water pressure can be affected and become more fluctuant when the thickness of the poroelastic soil layer decreases. The basic solutions may be attributed to a variety of wave propagation problems due to transient dynamic loading and illustrate the corresponding distinct wave features elegantly.","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"56 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143599379","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":"Novel Combined Mining Method: Calculation of Core Stope Structural Parameters","authors":"Quan Gan, Qingfa Chen, Wenxiong Yang, Chenyang Liu","doi":"10.1002/nag.3968","DOIUrl":"https://doi.org/10.1002/nag.3968","url":null,"abstract":"With increasing mining depth, the mining methods for steeply inclined medium‐thick ore bodies have become unsuitable. In this paper, by integrating the roof‐pillar induced caving technology, through technical fusion and reconstruction, a combined mining method of roof‐pillar induced caving and non‐pillar sublevel caving has been formulated. The five core parameters of the combined mining method (the ultimate length of the temporary top pillar <jats:italic>a</jats:italic><jats:sub>1</jats:sub>, thickness <jats:italic>h</jats:italic>, maximum hanging length <jats:italic>a</jats:italic><jats:sub>2</jats:sub>, initial induced caving step distance <jats:italic>L</jats:italic><jats:sub>1</jats:sub>, and continuous induced caving step distance <jats:italic>L</jats:italic><jats:sub>2</jats:sub>) are crucial for ensuring the stability of the mining system structure. A novel method combining qualitative and quantitative approaches is proposed to calculate the five core parameters. Initially, <jats:italic>a</jats:italic><jats:sub>1</jats:sub> is obtained through rock mass evaluation and the hydraulic radius inverse method. Subsequently, using Hu Haichang's thick plate theory, the relationship between the length and thickness of the thick plate is derived, and <jats:italic>h</jats:italic> and <jats:italic>a</jats:italic><jats:sub>2</jats:sub> are calculated by combining different trial functions and boundary conditions. Finally, <jats:italic>L</jats:italic><jats:sub>1</jats:sub> and <jats:italic>L</jats:italic><jats:sub>2</jats:sub> are determined based on the mining process of the combined mining method and the calculated values of <jats:italic>a</jats:italic><jats:sub>1</jats:sub>, <jats:italic>a</jats:italic><jats:sub>2</jats:sub>, and <jats:italic>h</jats:italic>. Taking the 37# experimental stope at the +220 m level of the Daxin manganese mine as a background, the calculated core parameters <jats:italic>a</jats:italic><jats:sub>1</jats:sub>, <jats:italic>h</jats:italic>, <jats:italic>a</jats:italic><jats:sub>2</jats:sub>, <jats:italic>L</jats:italic><jats:sub>1</jats:sub> and <jats:italic>L</jats:italic><jats:sub>2</jats:sub> are 47, 12, 39, 8, and 4.5 m, respectively. These calculated parameters ensure safe mining operations. The proposed combined mining method and core parameters calculation method can provide a technological breakthrough for the mining of medium‐depth ore bodies.","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"31 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143599381","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":"2.5D Numerical Formulation for Analysing Long‐Term Settlement of Tunnel‐Soil System Induced by Cyclic Train Loading in Soft Soil Area","authors":"Longxiang Ma, Hongyu Wang, Qin Yang, Chenxi Xue, Yi Li","doi":"10.1002/nag.3969","DOIUrl":"https://doi.org/10.1002/nag.3969","url":null,"abstract":"This paper presents an efficient two‐and‐a‐half dimensional (2.5D) numerical approach for analysing the long‐term settlement of a tunnel‐soft soil system under cyclic train loading. Soil deformations from train loads are divided into shear deformation under undrained conditions and volumetric deformation from excess pore water pressure (EPWP) dissipation. A 2.5D numerical model was employed to provide the dynamic stress state owing to the moving train load and the soil static stress state by the gravity effect for the determination of their accumulations. Then, an incremental computation approach combined with the initial strain approach in the framework of the 2.5D model was developed to compute the long‐term deformation of the tunnel‐soft soil system, considering the influence of the soil hardening due to EPWP dissipation. This approach helps to determine the distribution of the progressive settlement, transverse and longitudinal deformations in the tunnel‐soil system, overcoming traditional limitations. A comparison of settlements computed using this approach with measured settlements of a shield tunnel in soft soil shows good agreement, indicating the effectiveness of the proposed approach in analysing train‐induced progressive deformation of the tunnel‐soil system.","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"85 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143546233","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 Decomposition–Consolidation Model for the Production Behavior of Gas Hydrate‐Bearing Sediments","authors":"Zhigang Ye, Lujun Wang, Bin Zhu, Simin Yuan, Bingfa Yan, Ronghan Guo, Yunmin Chen","doi":"10.1002/nag.3965","DOIUrl":"https://doi.org/10.1002/nag.3965","url":null,"abstract":"Natural gas hydrates are the preferred alternative to traditional fossil fuels, estimated to store twice as much carbon. The gas hydrate‐bearing sediment (GHBS) is a representative degradable soil. During gas hydrate production, solid mass loss and pore liquid/gas generation occur, including both decomposition and consolidation processes of GHBS. These potentially trigger reservoir collapse, severely affecting production safety. This study develops a decomposition–consolidation model for GHBS, quantifying the solid hydrate loss by the kinetic decomposition equation and describing skeleton deformation via both modified elasticity and volumetric strain relationships. By linking hydrate saturation with the representative parameters of hydrate decomposition, mass migration, heat transfer, and skeleton deformation, decomposition degree and consolidation degree are respectively introduced to assess these processes. The decomposing and mechanical parameters are calibrated through triaxial/modeling tests. Results show that consolidation degree and decomposition degree are not synchronized in sandy hydrate‐bearing sediments, where depressurization‐induced variation of consolidation degree predominates in the early stage, while the evolution of consolidation degree lags behind decomposition degree for temperature recovery after complete hydrate decomposition; hydrate decomposition‐induced skeleton deformation, significant compared to pore pressure dissipation, remains crucial long after complete depressurization. These findings provide insights into optimizing safety of long‐term gas hydrate production.","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"179 1","pages":""},"PeriodicalIF":4.0,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143470739","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":"Macro- and Microscopic Mechanisms of Soil Arching Evolution Under the Impact of Noncentered Tunnel","authors":"Rui-Xiao Zhang,&nbsp;Dong Su,&nbsp;Xiang-Sheng Chen,&nbsp;Xing-Tao Lin,&nbsp;Hao Xiong,&nbsp;De-Jin Zhang","doi":"10.1002/nag.3962","DOIUrl":"10.1002/nag.3962","url":null,"abstract":"<div>\u0000 \u0000 <p>Further investigation into the progression of soil arching under the impact of noncentered tunnel is warranted. This study addresses this need by examining trapdoor models with varying vertical and horizontal spacings between the tunnel and the trapdoor through the discrete element method. The numerical model underwent calibration utilizing data from previous experiments. The results indicated that the soil arching ratio under the impact of noncentered tunnel exhibits four distinct stages: initial soil arching, maximum soil arching, load recovery, and ultimate stage, aligning with observations unaffected by tunnel presence. The minimal disparity in stress ratio within the stationary region was observed when the vertical spacing between the tunnel and the trapdoor ranges between 150 and 200 mm. Moreover, the disturbed area on the left part of the trapdoor extended significantly beyond the trapdoor width, with notably higher disturbance height compared to the right side. When the tunnel deviated from the centerline of the trapdoor, the stress enhancement on the right side was considerably greater compared to the left. Additionally, the displacement of the trapdoor resulted in a reduction of contact force anisotropy in the soil on the side more distant from the tunnel, while increasing it on the side closer to the tunnel.</p>\u0000 </div>","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":"49 7","pages":"1891-1910"},"PeriodicalIF":3.4,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143473555","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}