{"title":"用于压载建模的网格-离散元素混合法","authors":"","doi":"10.1007/s40571-024-00723-0","DOIUrl":null,"url":null,"abstract":"<h3>Abstract</h3> <p>Railway ballast modeling can be performed by different approaches, through continuous or discrete models, which have their comparative advantages and disadvantages, such as excessive volumes of material for testing and calibration steps. This paper aims to adapt and propose the use of the Hybrid Lattice-Discrete Element Method for modeling railway ballast aggregates. The advantages of using this technique for this purpose are: (i) one-step calibration of the rock material from laboratory test results; (ii) simulation of fractures in rock materials; (iii) visualization of micromechanical phenomena, such as particle slippage and fracture modes; (iv) realistic representation of various geometries compared to the conventional use of the Discrete Element Method. First, parameter calibration was performed from laboratory test results on granite rock obtained from the literature. Then, particle generation, Voronoi discretization and packing algorithms were used to build models of railway ballast samples. These models were used to simulate mechanical tests, namely single particle compression, confined uniaxial compression, monotonic triaxial compression and cyclic triaxial compression. There was consistency between the results and the empirical observations reported in the literature. In addition, variations in particle size distribution were observed during the simulations, as well as the causes of failure in each specimen, either by shear or particle breakage, in addition to the fracture modes of the ballast aggregates. By analyzing these elements together, knowledge is obtained about the phenomena occurring inside the railway ballast under different loading conditions, in addition to the results of strength, failure and deformation. Finally, it is concluded that the proposed method is effective for modeling railway ballast, besides being versatile, allowing to simulate the material for different loading configurations and boundary conditions.</p>","PeriodicalId":524,"journal":{"name":"Computational Particle Mechanics","volume":null,"pages":null},"PeriodicalIF":2.8000,"publicationDate":"2024-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Hybrid Lattice-discrete element method for ballast modeling\",\"authors\":\"\",\"doi\":\"10.1007/s40571-024-00723-0\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<h3>Abstract</h3> <p>Railway ballast modeling can be performed by different approaches, through continuous or discrete models, which have their comparative advantages and disadvantages, such as excessive volumes of material for testing and calibration steps. This paper aims to adapt and propose the use of the Hybrid Lattice-Discrete Element Method for modeling railway ballast aggregates. The advantages of using this technique for this purpose are: (i) one-step calibration of the rock material from laboratory test results; (ii) simulation of fractures in rock materials; (iii) visualization of micromechanical phenomena, such as particle slippage and fracture modes; (iv) realistic representation of various geometries compared to the conventional use of the Discrete Element Method. First, parameter calibration was performed from laboratory test results on granite rock obtained from the literature. Then, particle generation, Voronoi discretization and packing algorithms were used to build models of railway ballast samples. These models were used to simulate mechanical tests, namely single particle compression, confined uniaxial compression, monotonic triaxial compression and cyclic triaxial compression. There was consistency between the results and the empirical observations reported in the literature. In addition, variations in particle size distribution were observed during the simulations, as well as the causes of failure in each specimen, either by shear or particle breakage, in addition to the fracture modes of the ballast aggregates. By analyzing these elements together, knowledge is obtained about the phenomena occurring inside the railway ballast under different loading conditions, in addition to the results of strength, failure and deformation. Finally, it is concluded that the proposed method is effective for modeling railway ballast, besides being versatile, allowing to simulate the material for different loading configurations and boundary conditions.</p>\",\"PeriodicalId\":524,\"journal\":{\"name\":\"Computational Particle Mechanics\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":2.8000,\"publicationDate\":\"2024-03-07\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Computational Particle Mechanics\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://doi.org/10.1007/s40571-024-00723-0\",\"RegionNum\":3,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"MATHEMATICS, INTERDISCIPLINARY APPLICATIONS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Computational Particle Mechanics","FirstCategoryId":"5","ListUrlMain":"https://doi.org/10.1007/s40571-024-00723-0","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATHEMATICS, INTERDISCIPLINARY APPLICATIONS","Score":null,"Total":0}
Hybrid Lattice-discrete element method for ballast modeling
Abstract
Railway ballast modeling can be performed by different approaches, through continuous or discrete models, which have their comparative advantages and disadvantages, such as excessive volumes of material for testing and calibration steps. This paper aims to adapt and propose the use of the Hybrid Lattice-Discrete Element Method for modeling railway ballast aggregates. The advantages of using this technique for this purpose are: (i) one-step calibration of the rock material from laboratory test results; (ii) simulation of fractures in rock materials; (iii) visualization of micromechanical phenomena, such as particle slippage and fracture modes; (iv) realistic representation of various geometries compared to the conventional use of the Discrete Element Method. First, parameter calibration was performed from laboratory test results on granite rock obtained from the literature. Then, particle generation, Voronoi discretization and packing algorithms were used to build models of railway ballast samples. These models were used to simulate mechanical tests, namely single particle compression, confined uniaxial compression, monotonic triaxial compression and cyclic triaxial compression. There was consistency between the results and the empirical observations reported in the literature. In addition, variations in particle size distribution were observed during the simulations, as well as the causes of failure in each specimen, either by shear or particle breakage, in addition to the fracture modes of the ballast aggregates. By analyzing these elements together, knowledge is obtained about the phenomena occurring inside the railway ballast under different loading conditions, in addition to the results of strength, failure and deformation. Finally, it is concluded that the proposed method is effective for modeling railway ballast, besides being versatile, allowing to simulate the material for different loading configurations and boundary conditions.
期刊介绍:
GENERAL OBJECTIVES: Computational Particle Mechanics (CPM) is a quarterly journal with the goal of publishing full-length original articles addressing the modeling and simulation of systems involving particles and particle methods. The goal is to enhance communication among researchers in the applied sciences who use "particles'''' in one form or another in their research.
SPECIFIC OBJECTIVES: Particle-based materials and numerical methods have become wide-spread in the natural and applied sciences, engineering, biology. The term "particle methods/mechanics'''' has now come to imply several different things to researchers in the 21st century, including:
(a) Particles as a physical unit in granular media, particulate flows, plasmas, swarms, etc.,
(b) Particles representing material phases in continua at the meso-, micro-and nano-scale and
(c) Particles as a discretization unit in continua and discontinua in numerical methods such as
Discrete Element Methods (DEM), Particle Finite Element Methods (PFEM), Molecular Dynamics (MD), and Smoothed Particle Hydrodynamics (SPH), to name a few.