Computers and Geotechnics最新文献_第4页

Microscopic investigation of shape effect on local scour around the monopile using CFD-DEM 利用 CFD-DEM 对单桩周围局部冲刷的形状效应进行微观研究

IF 5.3 1区工程技术

Computers and Geotechnics Pub Date : 2024-11-03 DOI: 10.1016/j.compgeo.2024.106872

Dong Li , Ziying Zheng , Zheng Hu , Huihuan Ma

{"title":"Microscopic investigation of shape effect on local scour around the monopile using CFD-DEM","authors":"Dong Li , Ziying Zheng , Zheng Hu , Huihuan Ma","doi":"10.1016/j.compgeo.2024.106872","DOIUrl":"10.1016/j.compgeo.2024.106872","url":null,"abstract":"<div><div>Local scour refers to the erosion or migration of sedimental particles around bridge piers or abutments under the action of water flow. It can potentially undermine the hydraulic structures, resulting in catastrophic damage or even collapse. Under various hydraulic conditions, monopiles with diverse cross-sectional shapes have increasingly been applied to marine foundations. This study aims to investigate the effect of monopile shapes on scour development, and to establish a cross-scale connection between the macroscopic evolution of scour pits and the microscopic characteristics of sediments. The scour processes around monopiles are simulated using a coupled computational fluid dynamics and discrete element method (CFD-DEM). Four monopile shapes are examined, including circular, square, square with rounded corners, and diamond. Macroscopic characteristics such as seabed morphology, maximum scouring depth, and scour areas are analyzed, along with the microscopic characteristics such as the kinetic energy, drag force, and mechanical coordination number. The outcomes highlight that the diamond-shaped pile results in the greatest scour depth and widest scour areas compared to the other shapes. The incorporation of rounded pile corners improves flow characteristics and mitigate scour pit development. Furthermore, the local scour at different areas around the monopiles varies under the influence of different flow features.</div></div>","PeriodicalId":55217,"journal":{"name":"Computers and Geotechnics","volume":"177 ","pages":"Article 106872"},"PeriodicalIF":5.3,"publicationDate":"2024-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142572493","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

MatGBM: A Computer Vision-Aided Triangular Mesh Generator for High-Fidelity Grain-Based Model MatGBM：用于高保真纹理模型的计算机视觉辅助三角网格生成器

IF 5.3 1区工程技术

Computers and Geotechnics Pub Date : 2024-11-02 DOI: 10.1016/j.compgeo.2024.106871

Louis Ngai Yuen Wong, Zihan Liu

{"title":"MatGBM: A Computer Vision-Aided Triangular Mesh Generator for High-Fidelity Grain-Based Model","authors":"Louis Ngai Yuen Wong, Zihan Liu","doi":"10.1016/j.compgeo.2024.106871","DOIUrl":"10.1016/j.compgeo.2024.106871","url":null,"abstract":"<div><div>The grain-based model (GBM) stands as a renowned model for polycrystalline simulations in computational mechanics. Despite its popularity, there remains a critical need for a more advanced and user-friendly tool to generate high-fidelity microstructures with specified grain size distributions. Addressing this need, this paper introduces ’MatGBM’, an innovative modeling tool that aspires to enhance numerical simulations of polycrystalline materials. MatGBM seamlessly integrates three modules: a computer vision-aided mineral grain distribution detection, Voronoi tessellation processing, and triangular mesh generation. To accurately capture the two-dimensional structural characteristics of polycrystalline materials, the mineral grain distribution detection module employs computer vision functions to pinpoint particle coordinates and areas. The weighted Voronoi tessellation is generated and processed based on the original grain distribution features, resembling the original image of the polycrystalline material more closely than basic Voronoi tessellation. Finally, MatGBM directly outputs triangular mesh using two optional meshing tools based on the Voronoi polygons. Our rigorous testing via uniaxial compressive tests, Brazilian splitting tests, and three-point bending tests in crystalline rocks and metals, using the combined finite-discrete element method, validates that MatGBM can reliably reproduce the key deformation, damage, and failure characteristics of polycrystalline materials. Overall, MatGBM emerges not only as a promising tool for numerical simulations of rock, metallurgic, and ceramic materials, but also as a potent pre-processing tool for multiple numerical methods.</div></div>","PeriodicalId":55217,"journal":{"name":"Computers and Geotechnics","volume":"177 ","pages":"Article 106871"},"PeriodicalIF":5.3,"publicationDate":"2024-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142572490","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Three-dimensional dynamic responses of a layered transversely isotropic half-space with irregular interfaces using the thin layer method 使用薄层法测量具有不规则界面的分层横向各向同性半空间的三维动态响应

IF 5.3 1区工程技术

Computers and Geotechnics Pub Date : 2024-11-02 DOI: 10.1016/j.compgeo.2024.106851

Chao He , Xiaoxin Li , Shunhua Zhou , Hui Li , Xiaoqing Dong

{"title":"Three-dimensional dynamic responses of a layered transversely isotropic half-space with irregular interfaces using the thin layer method","authors":"Chao He , Xiaoxin Li , Shunhua Zhou , Hui Li , Xiaoqing Dong","doi":"10.1016/j.compgeo.2024.106851","DOIUrl":"10.1016/j.compgeo.2024.106851","url":null,"abstract":"<div><div>This paper proposes a thin layer method (TLM) for computing 3D dynamic responses in a layered transversely isotropic (TI) half-space with irregular interfaces. Utilizing Fourier transforms and modal superposition, stiffness matrices for semi-infinite and finite-length thin layer elements are derived, enabling the simulation of wave propagation in the finite-depth domain with irregular interfaces. The complex frequency shifted perfectly matched layer (CFSPML) within the TLM framework is developed to simulate wave attenuation in the underlying TI half-space, addressing the instability issues of the classical PML in the TI medium. The finite-length thin layer element can be of arbitrary length and is independent of the frequency, thus enhancing computational efficiency compared to discrete numerical methods like the FEM. The accuracy of the proposed method is verified with existing methodologies. The dynamic responses of a two-layered TI half-space with a Gaussian-shaped interface induced by either surface or buried dynamic point loads are investigated. The influences of the position and size of the irregular interface, as well as the transversely isotropy, are analyzed. Numerical results demonstrate that the presence of the irregular interface significantly changes the distribution of displacement fields. The influence of the irregular interface is highly dependent on the loading frequency and observation position.</div></div>","PeriodicalId":55217,"journal":{"name":"Computers and Geotechnics","volume":"177 ","pages":"Article 106851"},"PeriodicalIF":5.3,"publicationDate":"2024-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142572491","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The combined effect of particle angularity and inter-particle friction on micro- and macroscopic properties of granular assemblies 颗粒角度和颗粒间摩擦对颗粒集合体微观和宏观特性的综合影响

IF 5.3 1区工程技术

Computers and Geotechnics Pub Date : 2024-10-31 DOI: 10.1016/j.compgeo.2024.106850

Dominik Krengel , Haoran Jiang , Jian Chen , Takashi Matsushima

{"title":"The combined effect of particle angularity and inter-particle friction on micro- and macroscopic properties of granular assemblies","authors":"Dominik Krengel , Haoran Jiang , Jian Chen , Takashi Matsushima","doi":"10.1016/j.compgeo.2024.106850","DOIUrl":"10.1016/j.compgeo.2024.106850","url":null,"abstract":"<div><div>Both inter-particle friction and particle shape are known to influence the micro- and macroscopic properties of granular assemblies individually. However their combined influence is still poorly understood. In this work we perform a series of Discrete Element Simulations to systematically study the combined effect of particle angularity and friction on the shear resistance of granular aggregates. We find that for angular particles the residual shear resistance as a function of inter-particle friction shows a local maximum, while for round particles it increases monotonically until it saturates. In contrast, no such effect is observed in the packing structure of the aggregates. The non-monotonic behaviour of angular particles is mirrored by the critical state directional and normal force fabric anisotropies, while the tangential normal force anisotropy shows more similarity to the bulk porosity and the mobilization of friction at the individual particle contacts. Our results now provide a much clearer picture on the origin of the non-monotonic behaviour of the critical state shear resistance on the inter-particle friction, as a competition between sliding and rolling in two different rolling regimes.</div></div>","PeriodicalId":55217,"journal":{"name":"Computers and Geotechnics","volume":"177 ","pages":"Article 106850"},"PeriodicalIF":5.3,"publicationDate":"2024-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142553512","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Ultimate lateral bearing capacity of rigid pile in clay considering soil stress history and scour-hole dimension 考虑土壤应力历史和冲孔尺寸的粘土中刚性桩的极限侧向承载力

IF 5.3 1区工程技术

Computers and Geotechnics Pub Date : 2024-10-30 DOI: 10.1016/j.compgeo.2024.106848

Mingke Lin , Changbing Qin , Siyu Li , Jiangtao Yi

{"title":"Ultimate lateral bearing capacity of rigid pile in clay considering soil stress history and scour-hole dimension","authors":"Mingke Lin , Changbing Qin , Siyu Li , Jiangtao Yi","doi":"10.1016/j.compgeo.2024.106848","DOIUrl":"10.1016/j.compgeo.2024.106848","url":null,"abstract":"<div><div>Rigid monopiles in a marine environment are frequently subjected to severe lateral loads and scour effects, which complicates the stability assessment of monopiles. This paper proposes a ‘double failure mechanism’ that integrates the meniscus-conical failure wedge and rotational failure model to evaluate the ultimate lateral bearing capacity of a rigid pile in clay under scour conditions. Considering the influence of scour-hole, three distinct failure modes are introduced based on the possible ranges of failure. The critical ‘double failure mechanism’ can satisfy both the force balance and the moment balance of the pile-soil system. Based on this framework, an analytical solution for the ultimate lateral bearing capacity of a rigid monopile with considerations of these three failure modes is derived using the limit equilibrium method. Additionally, the combined effects of additional stress and stress history on soil properties are accurately analyzed. The FEM results and existing theoretical solutions are employed to validate the derived limit equilibrium solution. Finally, the effects of scour-hole dimensions and load eccentricity on the ultimate lateral bearing capacity of a rigid monopile, wedge failure and rotational failure are investigated.</div></div>","PeriodicalId":55217,"journal":{"name":"Computers and Geotechnics","volume":"177 ","pages":"Article 106848"},"PeriodicalIF":5.3,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142553505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Numerical investigations of the mechanical properties and energy characteristics of sandy cobble strata considering its internal stochastic structures 考虑内部随机结构的砂卵石地层力学性能和能量特征的数值研究

IF 5.3 1区工程技术

Computers and Geotechnics Pub Date : 2024-10-30 DOI: 10.1016/j.compgeo.2024.106867

Fan Wang , Pengfei Li , Xiuli Du , Jianjun Ma , Lin Wang

{"title":"Numerical investigations of the mechanical properties and energy characteristics of sandy cobble strata considering its internal stochastic structures","authors":"Fan Wang , Pengfei Li , Xiuli Du , Jianjun Ma , Lin Wang","doi":"10.1016/j.compgeo.2024.106867","DOIUrl":"10.1016/j.compgeo.2024.106867","url":null,"abstract":"<div><div>Investigating the mechanical properties of sandy cobble strata is essential for optimizing the design and construction of urban tunnels, thereby controlling ground deformation and ensuring tunnel stability. This paper aims to comprehensively investigate the mechanical properties and energy characteristics of heterogeneous sandy cobble strata. Numerical simulations are employed to examine the stress–strain behavior and energy evolution mechanism in scenarios with and without interfaces between the soil matrix and blocks. Subsequent analysis focuses on elucidating the effects of the internal stochastic structures, which characterize heterogeneity, on the overall strength and energy characteristics. The results indicate that the presence of interfaces significantly compromises the overall strength, while exacerbating the occurrence of a tortuous plastic zone around blocks. The volumetric block proportion (<em>VBP</em>), which represents the volumetric content of cobbles, has a significant impact on the overall mechanical behaviour. In the context of high <em>VBP</em>, block sizes, counts and orientations play substantial roles. Finally, the discussion reveals that when blocks are modelled using the elastic model, the overall strength is significantly overestimated compared to the strain-softening and Mohr-Counlomb models, especially in scenarios with high <em>VBP</em> and in-situ stress. It provides an unsafe evaluation (i.e., overestimation) of tunnel stability.</div></div>","PeriodicalId":55217,"journal":{"name":"Computers and Geotechnics","volume":"177 ","pages":"Article 106867"},"PeriodicalIF":5.3,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142553508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Calibration and intelligent optimization for DEM numerical parameters in heterogeneous rock mass 校准和智能优化异质岩体中的 DEM 数值参数

IF 5.3 1区工程技术

Computers and Geotechnics Pub Date : 2024-10-30 DOI: 10.1016/j.compgeo.2024.106863

Runpeng Shang , Yugui Yang , Bingxiang Huang , Yong Chen , Chao Qiu , Wang Liu

{"title":"Calibration and intelligent optimization for DEM numerical parameters in heterogeneous rock mass","authors":"Runpeng Shang , Yugui Yang , Bingxiang Huang , Yong Chen , Chao Qiu , Wang Liu","doi":"10.1016/j.compgeo.2024.106863","DOIUrl":"10.1016/j.compgeo.2024.106863","url":null,"abstract":"<div><div>Calibrating meso parameters is a crucial step in modeling rock materials using the Distinct Element Method (DEM). Improved calibration methods integrating machine learning and optimization algorithms have been proposed to revise the time-consuming conventional trial-and-error approach. This study introduces an innovative calibration method for heterogeneous DEM numerical parameters, optimized with the improved DBO algorithm (IDBO) utilizing Latin Hypercube Sampling combined with Gaussian Processes (GP-LHS) for initialization and hybrid strategies for iteration. Findings suggest the proposed enhanced heterogeneous DEM calibration method can accurately reproduce laboratory results and similar material experiments. Additionally, this method performs better than the DBO-DEM, PSO-DEM, and GA-DEM calibration methods in heterogeneous DEM parameters calibration speed with the same accuracy requirement during unconfined compression tests. The findings affirm the potential of the method for heterogeneous DEM numerical parameters calibration.</div></div>","PeriodicalId":55217,"journal":{"name":"Computers and Geotechnics","volume":"177 ","pages":"Article 106863"},"PeriodicalIF":5.3,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142553509","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A plastic-damage cohesive zone model for shear rupture band in geomaterials under mixed-mode and cyclic loading 混合模式和循环加载下土工材料剪切断裂带的塑性破坏内聚区模型

IF 5.3 1区工程技术

Computers and Geotechnics Pub Date : 2024-10-30 DOI: 10.1016/j.compgeo.2024.106829

Xiao Miao, Daosheng Ling, Anhao Pan, Hai Wang

{"title":"A plastic-damage cohesive zone model for shear rupture band in geomaterials under mixed-mode and cyclic loading","authors":"Xiao Miao, Daosheng Ling, Anhao Pan, Hai Wang","doi":"10.1016/j.compgeo.2024.106829","DOIUrl":"10.1016/j.compgeo.2024.106829","url":null,"abstract":"<div><div>The characterization of the mechanical behavior of the shear rupture band is essential to the analysis of the strain localization failure of geotechnical structures, with a key focus on describing the plastic-damage behavior and dilatancy of the geomaterial. A novel plastic-damage cohesive zone model is presented based on the unified plastic-damage modeling framework, in which an enhanced dilatancy angle evolution law is put forward to capture the dilatancy, and the yield function and the dissipation potential function are proposed to account for the tension/compression-shear coupling effect. The capability of the proposed model is demonstrated by its constitutive responses under several typical monotonic and cyclic loading paths, and further validated by simulating three laboratory tests of rock joint and silt-steel interface. The notable agreement between the simulation results and their experimental counterparts illustrates the effectiveness of the proposed model in characterizing the mechanical behavior of the shear rupture band under mixed-mode and cyclic loading conditions, including post-peak hardening/softening, plastic-damage behavior, and hysteresis.</div></div>","PeriodicalId":55217,"journal":{"name":"Computers and Geotechnics","volume":"177 ","pages":"Article 106829"},"PeriodicalIF":5.3,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142553511","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Upper bound stability analysis of single-layered slurry trenches in clay using the perturbation method 采用扰动法对粘土中的单层泥浆沟进行上限稳定性分析

IF 5.3 1区工程技术

Computers and Geotechnics Pub Date : 2024-10-30 DOI: 10.1016/j.compgeo.2024.106864

Tingzhen Tan , Maosong Huang , Zhenhao Shi

引用次数: 0

Efficient simulation of 3D conditional random field using kriging with Gaussian-process trend 利用具有高斯过程趋势的克里金法高效模拟三维条件随机场

IF 5.3 1区工程技术

Computers and Geotechnics Pub Date : 2024-10-30 DOI: 10.1016/j.compgeo.2024.106862

Jianye Ching , Ikumasa Yoshida

引用次数: 0