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

{"title":"Microscopic Thermo‐Mechanical Properties and Phase Transition of Bulk Ice‐Ih","authors":"Pengchang Wei, Weiwei Niu, Chi Yao, Zhenyu He, Yuan‐Yuan Zheng, Wei Ma","doi":"10.1002/nag.3856","DOIUrl":"https://doi.org/10.1002/nag.3856","url":null,"abstract":"The ice–water phase transition of bulk ice could develop with varying temperatures and external loads, significantly affecting its mechanical properties. The coupling effect of temperature and shear loads on the thermo‐mechanical properties of bulk ice and its phase transition evolution is poorly understood, especially at the nanoscale. In this study, molecular dynamics (MD) simulation method was employed to investigate the thermo‐mechanical behaviours of bulk ice‐Ih system at the microscale under various temperatures (73–270 K) and shear paths, where its phase transition, elastic properties, structure deformation mechanism and structural anisotropy were discussed. The simulation results show that (1) the shear modulus, shear strength and ultimate shear strain of bulk ice‐Ih system could linearly decrease with rising temperature, aligning with previous studies. (2) Two types of failure modes from bulk ice‐Ih system were founded, such as solid–liquid phase co‐existence at 73–225 K and liquid phase at 250–270 K. (3) Ice melting into water was attributed to the fracture of hydrogen bond during shear process. (4) Compared to vertical shearing (<jats:italic>XZ</jats:italic> () and <jats:italic>YZ</jats:italic> ()) directions, the mechanical response along the horizontal shearing (<jats:italic>XY</jats:italic> (0001)) direction was most sensitive to temperature effect.","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142374122","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":"3D Semi‐Analytical and Numerical Upper‐Bound Homogenisation Approaches to the Out‐of‐Plane Strength Domain of a Running‐Bond Masonry Wall","authors":"Elodie Donval, Ghazi Hassen, Duc Toan Pham, Patrick de Buhan, Martin Vigroux","doi":"10.1002/nag.3851","DOIUrl":"https://doi.org/10.1002/nag.3851","url":null,"abstract":"The present contribution proposes a new semi‐analytical homogenisation approach to determine a running‐bond masonry wall's in‐ and out‐of‐plane strength domain based on the yield design framework. The main novelty of such an approach is that it does not rely on simplifying assumptions such as infinitely thin joints or plane stress state within the blocks, by making use of 3D virtual failure mechanisms in the kinematic approach. The new semi‐analytical approach is then compared to a state‐of‐the‐art numerical implementation of the kinematic approach of yield design, relying on semi‐definite programming. Several comparisons show a good agreement between the semi‐analytical and the numerical approaches and outline the computational efficiency of the semi‐analytical approach as well as the fact that it is very well suited for engineering design purposes. Both proposed approaches are then compared to existing approaches based on the limit analysis or yield design framework.","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142369084","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 2D Electro‐Osmotic Consolidation of Unsaturated Soil With Non‐linear Voltage Distribution","authors":"Xudong Zhao, Jie Min, Shaolin Ding, Yang Liu, Jiaxin Liao, Shuai Zhang","doi":"10.1002/nag.3854","DOIUrl":"https://doi.org/10.1002/nag.3854","url":null,"abstract":"Existing solutions for electro‐osmotic consolidation assume a linear voltage distribution, which is inconsistent with the experimental findings. The present study introduces a novel two‐dimensional electro‐osmotic consolidation model for unsaturated soils, which considers the influence of non‐linear voltage distribution. The closed‐form solution is derived by employing the eigenfunction expansion method and the Laplace transform technique. The accuracy of the analytical solutions is validated through the implementation of finite element simulations. The findings from the parametric studies indicate that the excess pore water pressure (EPWP) observed in electro‐osmotic consolidation is influenced by the distribution of voltage. The dissipation rate of EPWP is observed to be higher when subjected to non‐linear voltage conditions compared to linear voltage conditions. Moreover, the impact of non‐linear voltage distribution becomes more pronounced in unsaturated soil characterised by higher electro‐osmosis conductivity and a lower ratio of <jats:italic>k<jats:sub>x</jats:sub>/k<jats:sub>y</jats:sub></jats:italic>. In contrast, the excess pore air pressure (EPAP) remains unaffected by the voltage distribution.","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142329002","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":"Intelligent Parameter Identification for a High‐Cycle Accumulation Model of Sand With Enhancement of Cuckoo Search Algorithm","authors":"Shao‐Heng He, Zhen‐Yu Yin, Yifei Sun, Zhi Ding","doi":"10.1002/nag.3838","DOIUrl":"https://doi.org/10.1002/nag.3838","url":null,"abstract":"This study presents a novel approach of intelligent parameter identification (IPI) for a high‐cycle accumulation (HCA) model of sand, which reduces the subjective errors on manual parameter calibration and makes the use of the HCA model more accessible. The technique is based on optimization theory and adopts the cuckoo search algorithm (CSA). To improve search ability and convergence speed of CSA, several enhancements are implemented. First, the improved CSA (ICSA) incorporates quasi‐opposition learning to expand the search space and replaces the original search strategy with a Cauchy random walk to enhance global search ability. Second, an adaptive scaling factor is introduced in the algorithm's control parameters to achieve a better balance between exploration speed and accuracy. Third, a dynamic inertia weight is used to balance the search between global and local spaces when generating new nest positions after abandoning old ones. The performance of the ICSA‐based IPI approach is evaluated by comparing it with the original CSA‐based IPI and manual calibration in determining the HCA model parameters. A comprehensive analysis is also conducted to assess the effectiveness and superiority of each improvement strategy introduced in the ICSA over the original CSA. All comparisons demonstrate that the proposed ICSA‐based IPI method is more powerful and efficient in finding optimal parameters.","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142328665","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":"Lateral Dynamic Impedances of Pile Embedded in Saturated Soil Considering Local Debonding at the Pile–Soil Interface","authors":"Nansheng Ding, Zhaowei Ding, Qihua Zhao","doi":"10.1002/nag.3849","DOIUrl":"https://doi.org/10.1002/nag.3849","url":null,"abstract":"An analytical solution based on the infinite layer theory of Novak and Biot's consolidation equation is developed in this study to evaluate the impact of local debonding occurring at the pile–soil interface. The potential functions are employed to decouple the differential equations that govern the soil deformations, while the dynamic resistances of soil are determined from the boundary conditions at the pile–soil interface in accordance with computational theory for mixed boundary problems. The Adomian decomposition method is introduced to obtain the dynamic impedances of pile. The effects of local debonding on the dynamic resistances of soil are investigated by comparing the results from the present solution with available schemes based on perfect contact assumption. The influences of pile–soil modulus ratio, exciting frequency, soil permeability, and slenderness ratio of pile while considering local debonding were then examined. The numerical results indicate that the local debonding occurring at the pile–soil interface dramatically weakened the lateral dynamic impedances of pile, and this trend was particularly pronounced at high frequency and small modulus ratio. Additionally, the local debonding phenomenon also imposes limitations on the implementation of the equivalent single‐phase solution in practical engineering applications. The presented solution theoretically demonstrates the significant impact of local debonding on the dynamic response of piles embedded in saturated soil and may provide insight into determining parameter values in empirical equations.","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142329003","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":"Decoding Methane Flow in Fractured Clay: A Semi‐Analytical Model With Matrix Diffusion and Advection","authors":"Qiao Wang, Fusheng Zha, Hamid Rajabi, Long Xu, Huaxiang Yan","doi":"10.1002/nag.3853","DOIUrl":"https://doi.org/10.1002/nag.3853","url":null,"abstract":"Landfills emissions, ranking as the third‐largest anthropogenic source of methane in the atmosphere, pose environmental challenges and threaten public health. The pivotal role of clay as a mitigating agent for methane emission within landfill cover systems cannot be overstated; however, our understanding of methane escape from fractured clay remains limited. This study aims to address the existing gaps by proposing a robust analytical model of methane transport in both fractures and clay matrix. Our investigation also includes a dimensionless analysis to govern the relative significance of diffusion and advection in methane emission from fractured clay, systematically reviewing factors such as the degree of water saturation (<jats:italic>Sr</jats:italic>) and fracture width. The methane concentration profiles in cracked clay demonstrated escalating sensitivity to Péclet (<jats:italic>Pe</jats:italic>) numbers, especially when advection dominates transport. Our findings also highlight the prevalence of preferential methane flow with increasing <jats:italic>Sr</jats:italic> in the clay matrix. The flux of methane emission from fractures at <jats:italic>Sr</jats:italic> = 0.8 was 130 times greater than that from intact clay. However, the study necessitates considering methane emission from clay matrix, particularly in dry clay conditions (<jats:italic>Sr</jats:italic> = 0.2 and 0.4). The accumulated methane emission flux from intact clay, more than that emitted from fractures by about 2.5 times at <jats:italic>Sr</jats:italic> = 0.2, was 1.3 × 10<jats:sup>−5</jats:sup> g/m/s. The findings significantly advance the understanding of gas transport in fractured geomaterials, revealing the effect of water saturation and crack width on methane emissions from fractures. Overall, the outcomes emphasize the inclusion importance of methane emission from cracked clay in the design of gas barriers.","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142329001","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":"Theoretical Analysis and Field Investigation on Bearing Characteristics of the Long‐Core SDCM Pile Under Vertical Load in Multilayered Soil","authors":"Zhiyu Gong, Guoliang Dai, Hongbo Liu, Xinsheng Chen, Haoran Ouyang, Jianxiong Jiang","doi":"10.1002/nag.3835","DOIUrl":"https://doi.org/10.1002/nag.3835","url":null,"abstract":"The long‐core SDCM pile is a typical type of stiffened deep cement mixing (SDCM) pile, it could be widely exploited in coastal geotechnical engineering because of its high bearing capacity, low settlement, green, and economic advantages. The long‐core SDCM pile is constituted by a PHC pipe pile and cemented soil, the height of the PHC pipe pile is upward than the depth of the cemented soil reinforcement. This study implements a theoretical approach to load transfer analysis of the long‐core SDCM pile under vertical load in layer soil. Herein, the shear constitutive models of the DCM pile‐PHC pipe pile interface and the fictitious soil pile‐PHC pipe pile interface are double exponential models, the compression constitutive model of the soil under the pile and the shear constitutive models of the DCM pile–soil interface and the fictitious soil pile–soil interface are ideal elastic–plastic models. The results obtained from this calculation model can match well with the data from on‐site tests and other analytical solutions. The theoretical model is used to analyze the key parameters <jats:italic>L</jats:italic><jats:sub>D</jats:sub>/<jats:italic>L</jats:italic><jats:sub>P</jats:sub>, <jats:italic>D</jats:italic><jats:sub>D</jats:sub>/<jats:italic>D</jats:italic><jats:sub>P</jats:sub>, <jats:italic>E</jats:italic><jats:sub>c</jats:sub>, and <jats:italic>E</jats:italic><jats:sub>p</jats:sub> of the long‐core SDCM pile. The <jats:italic>L</jats:italic><jats:sub>D</jats:sub>/<jats:italic>L</jats:italic><jats:sub>P</jats:sub> and <jats:italic>D</jats:italic><jats:sub>D</jats:sub>/<jats:italic>D</jats:italic><jats:sub>P</jats:sub> are the critical parameters affecting the bearing characteristics, and the minor settlement is affected by the changes of <jats:italic>E</jats:italic><jats:sub>c</jats:sub> and <jats:italic>E</jats:italic><jats:sub>p</jats:sub>.","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142325568","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 Prediction Model for Debris Flow Mean Velocity Based on Small Sample Data Taking Jiangjia Gully Watershed as an Example","authors":"He Wei Kuang, Zhi Yong Ai, Gan Lin Gu","doi":"10.1002/nag.3850","DOIUrl":"https://doi.org/10.1002/nag.3850","url":null,"abstract":"Among all the factors affecting the destructiveness of debris flow, the mean velocity is one of the most important characteristics. In this paper, we aim to apply a particle swarm optimization (PSO) based on the relevance vector machine (RVM) to predict the mean velocity. The PSO is used to optimize kernel parameters inside the RVM, whereas the RVM is responsible for completing the prediction task. Through sample training, a nonlinear relationship can be obtained, enabling a rapid prediction of the mean velocity for new samples. The debris flow dataset of Jiangjia Gully is used to evaluate the performance of PSO‐RVM in this study. Besides, we further compare the prediction results of PSO‐RVM with other prominent approaches, for example, the support vector machine (SVM), BP neural network (BP), and the RVM. The results show that the mean relative error (MRE) of PSO‐RVM is only 0.69%. In addition, BP yields the highest MRE (27.61%), and the MRE (2.75%) corresponding to the RVM is lower than that (5.98%) yielded by the SVM. For the root mean square error (RMSE) and Theil's inequality coefficient (TIC), the PSO‐RVM method still generates much lower RMSE (6.48%) and TIC (0.179%) values than the other three methods. Overall, compared with current debris flow prediction models, the PSO‐RVM achieves high prediction accuracy, fewer optimization parameters, and low computational complexity. Finally, a sensitivity analysis is conducted to explore the dominative factors of debris flow.","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142325448","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":"Determination of Compaction Parameters of Cement‐Lime Soils: Boosting‐Based Ensemble Models","authors":"Yonas Tilahun, Xiao Qinghua, Argaw Asha Ashongo, Xiangyu Han","doi":"10.1002/nag.3846","DOIUrl":"https://doi.org/10.1002/nag.3846","url":null,"abstract":"This study investigates the application of artificial intelligence (AI) models to predict soil compaction characteristics, specifically maximum dry density (<jats:italic>M</jats:italic><jats:sub>DD</jats:sub>) and optimum moisture content (<jats:italic>O</jats:italic><jats:sub>MC</jats:sub>), which are critical for stabilizing construction foundations. Traditional methods for determining <jats:italic>M</jats:italic><jats:sub>DD</jats:sub> and <jats:italic>O</jats:italic><jats:sub>MC</jats:sub> are labor‐intensive and often influenced by factors such as soil type, plasticity, and compaction energy (<jats:italic>E</jats:italic>). The research employed AI models, including random forest regression (RF‐R), gradient boosting regression (GB‐R), XGBoosting regressor (XGB‐R), and multilinear regression (ML‐R), trained on a comprehensive dataset of soil properties. For the first time, compaction energy has been used as an input variable to predict soil cement lime stabilized compaction parameters. Among the models, GB‐R demonstrated the highest prediction accuracy for <jats:italic>M</jats:italic><jats:sub>DD</jats:sub> and <jats:italic>O</jats:italic><jats:sub>MC</jats:sub>, outperforming RF‐R, XGB‐R, and ML‐R. The performance of built‐in models has been measured by three new index performance metrics: the a20‐index, the index of scatter (IS), and the index of agreement (IA), in addition to four common metrics. Taylor diagrams confirmed the robustness of these predictions during lab testing. A sensitivity analysis revealed that <jats:italic>M</jats:italic><jats:sub>DD</jats:sub> and <jats:italic>O</jats:italic><jats:sub>MC</jats:sub> were most influenced by plastic limit (PL), compaction energy (<jats:italic>E</jats:italic>), liquid limit (LL), and plasticity index (PI). Additionally, curve‐fitting techniques were applied to model the relationship between <jats:italic>M</jats:italic><jats:sub>DD</jats:sub>, <jats:italic>O</jats:italic><jats:sub>MC</jats:sub>, and these key factors. The results indicated that the GB‐R model, particularly when focused on essential features, provided superior accuracy compared to traditional regression methods, offering a reliable tool for soil stabilization assessments in construction.","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142325569","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":"Computational Simulation and Experimental Analysis on Wearing Mechanisms of Gypsum and Concrete Samples in Pin‐on‐Disk ASTM Abrasion Testing","authors":"Jinwei Fu, Vahab Sarfarazi, Hadi Haeri, Behzad Tolaminejad, Soheil Abharian, Haleh Rasekh, Manoj Khandelwal, Mohammad Fatehi Marji","doi":"10.1002/nag.3848","DOIUrl":"https://doi.org/10.1002/nag.3848","url":null,"abstract":"Mechanical excavation machines, like continuous miners and road headers, have been broadly used in tunneling and underground and surface mines. The disc cutters are seated on the different cutter heads’ to cut different parts of the tunnel face. With the increase in the cutters’ size and power, the cutting disc cutters’ capacity has been extended to cut moderate and tough rock types. This experimental and numerical research includes the application of, “Pin‐on‐Disk” ASTM abrasion testing, in which the failure mechanism of an interface between both the rock‐like samples and (WC–Co) tungsten carbide has been investigated under different confining pressures. The research aims to investigate the wear mechanism of gypsum and concrete samples. The Particle Flow Code in three dimensions (PFC3D) was used for test simulations concurrently with the experimental setup. A drilling pin with a diameter of 0.4 m was positioned above the model. The pin was inserted into the model at speeds of 0.01 mm/s at depths of 1, 3, and 5 m. A total of nine lab tests were conducted. The tensile strength of the material was 2.5 MPa. The results show that the values of volume lost for the gypsum and concrete discs were detected as a function of sliding length, fitting to non‐linear behavior. The wearing depth increased by increasing the loading force. Under constant loading force, the gypsum sample wears more than the concrete sample because gypsum is less strong than concrete. The PFC generates useful findings that experimental tests cannot provide.","PeriodicalId":13786,"journal":{"name":"International Journal for Numerical and Analytical Methods in Geomechanics","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142325449","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}