{"title":"压缩和剪切对硅砂和石灰砂颗粒破碎的影响","authors":"Andrzej Głuchowski, Linzhu Li, Magued Iskander","doi":"10.1007/s11440-024-02339-3","DOIUrl":null,"url":null,"abstract":"<div><p>Changes in particle granulometry could lead to significant changes in a\n soil’s behavior, making an understanding of micro-scale granulometry essential for\n practical applications. Changes in particle size, shape, and particle size distribution\n could result from a combination of applied normal and shearing stresses, which can in\n turn influence further response of the material. This study explored particle breakage\n during both compressive and shear loading under typical stresses. A deeper understanding\n of the phenomenon requires distinguishing broken and unbroken grains at the particle\n scale. Dynamic Image Analysis (DIA) was therefore employed to quantify changes in\n particle granulometry in two sands, a siliceous Ottawa sand and a calcareous sand known\n as Fiji Pink. Pre-sorted specimens having similar size, granulometry, and particle size\n distributions were tested using both oedometric and direct shear tests having the same\n aspect ratio, facilitating a direct comparison of the effects of shearing and\n compression on similar materials having different mineralogy. A breakage index was used\n for prognosis of particle breakage at key reference diameters. During oedometric tests,\n grain breakage was limited in both sands at stresses up to 1.2 MPa, but it increased\n significantly during direct shear tests. A conceptual model was proposed to explain the\n particle breakage mechanism during shear, at four key phase points representing (1)\n maximum compaction, (2) transition from compaction to dilative behavior, (3) maximum\n shear stress, and (4) peak test strain. In addition, a loading intensity framework was\n adopted to explain the relative roles of normal and shearing stresses on particle\n breakage. An increase of fines in soil during shearing was also observed and related to\n two sources: coarser grain abrasion and finer particle crushing. The vulnerability of\n grains with more anisotropic shapes was also observed. The loading intensity framework\n suggested that attrition of particle diameter could be divided into two phases, with a\n transitional critical loading intensity that appeared constant for each sand. For Ottawa\n sand, abrasion was the primary mechanism observed, causing a significant increase in\n Aspect Ratio (<i>AR</i>) and Sphericity (<i>S</i>) for finer grains. For Fiji sand, a transition from\n abrasion to attrition was noted, leading to limited sphericity decrease for the largest\n particles. Finer particles cushioning larger Fiji sand particles are more prone to\n breakage, resulting in increased <i>AR</i> and <i>S</i>. Finally, test results were used to propose a simple\n hyperbolic model to predict evolution of the particle size distribution during shear,\n for sands. The model was also verified using published data on grain evolution during\n shear of a different sand, not employed in its development.</p></div>","PeriodicalId":49308,"journal":{"name":"Acta Geotechnica","volume":"19 11","pages":"1 - 27"},"PeriodicalIF":5.6000,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Effect of compression and shear on particle\\n breakage of silica and calcareous sands\",\"authors\":\"Andrzej Głuchowski, Linzhu Li, Magued Iskander\",\"doi\":\"10.1007/s11440-024-02339-3\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Changes in particle granulometry could lead to significant changes in a\\n soil’s behavior, making an understanding of micro-scale granulometry essential for\\n practical applications. Changes in particle size, shape, and particle size distribution\\n could result from a combination of applied normal and shearing stresses, which can in\\n turn influence further response of the material. This study explored particle breakage\\n during both compressive and shear loading under typical stresses. A deeper understanding\\n of the phenomenon requires distinguishing broken and unbroken grains at the particle\\n scale. Dynamic Image Analysis (DIA) was therefore employed to quantify changes in\\n particle granulometry in two sands, a siliceous Ottawa sand and a calcareous sand known\\n as Fiji Pink. Pre-sorted specimens having similar size, granulometry, and particle size\\n distributions were tested using both oedometric and direct shear tests having the same\\n aspect ratio, facilitating a direct comparison of the effects of shearing and\\n compression on similar materials having different mineralogy. A breakage index was used\\n for prognosis of particle breakage at key reference diameters. During oedometric tests,\\n grain breakage was limited in both sands at stresses up to 1.2 MPa, but it increased\\n significantly during direct shear tests. A conceptual model was proposed to explain the\\n particle breakage mechanism during shear, at four key phase points representing (1)\\n maximum compaction, (2) transition from compaction to dilative behavior, (3) maximum\\n shear stress, and (4) peak test strain. In addition, a loading intensity framework was\\n adopted to explain the relative roles of normal and shearing stresses on particle\\n breakage. An increase of fines in soil during shearing was also observed and related to\\n two sources: coarser grain abrasion and finer particle crushing. The vulnerability of\\n grains with more anisotropic shapes was also observed. The loading intensity framework\\n suggested that attrition of particle diameter could be divided into two phases, with a\\n transitional critical loading intensity that appeared constant for each sand. For Ottawa\\n sand, abrasion was the primary mechanism observed, causing a significant increase in\\n Aspect Ratio (<i>AR</i>) and Sphericity (<i>S</i>) for finer grains. For Fiji sand, a transition from\\n abrasion to attrition was noted, leading to limited sphericity decrease for the largest\\n particles. Finer particles cushioning larger Fiji sand particles are more prone to\\n breakage, resulting in increased <i>AR</i> and <i>S</i>. Finally, test results were used to propose a simple\\n hyperbolic model to predict evolution of the particle size distribution during shear,\\n for sands. The model was also verified using published data on grain evolution during\\n shear of a different sand, not employed in its development.</p></div>\",\"PeriodicalId\":49308,\"journal\":{\"name\":\"Acta Geotechnica\",\"volume\":\"19 11\",\"pages\":\"1 - 27\"},\"PeriodicalIF\":5.6000,\"publicationDate\":\"2024-05-08\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Acta Geotechnica\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://link.springer.com/article/10.1007/s11440-024-02339-3\",\"RegionNum\":1,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"ENGINEERING, GEOLOGICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Acta Geotechnica","FirstCategoryId":"5","ListUrlMain":"https://link.springer.com/article/10.1007/s11440-024-02339-3","RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENGINEERING, GEOLOGICAL","Score":null,"Total":0}
Effect of compression and shear on particle
breakage of silica and calcareous sands
Changes in particle granulometry could lead to significant changes in a
soil’s behavior, making an understanding of micro-scale granulometry essential for
practical applications. Changes in particle size, shape, and particle size distribution
could result from a combination of applied normal and shearing stresses, which can in
turn influence further response of the material. This study explored particle breakage
during both compressive and shear loading under typical stresses. A deeper understanding
of the phenomenon requires distinguishing broken and unbroken grains at the particle
scale. Dynamic Image Analysis (DIA) was therefore employed to quantify changes in
particle granulometry in two sands, a siliceous Ottawa sand and a calcareous sand known
as Fiji Pink. Pre-sorted specimens having similar size, granulometry, and particle size
distributions were tested using both oedometric and direct shear tests having the same
aspect ratio, facilitating a direct comparison of the effects of shearing and
compression on similar materials having different mineralogy. A breakage index was used
for prognosis of particle breakage at key reference diameters. During oedometric tests,
grain breakage was limited in both sands at stresses up to 1.2 MPa, but it increased
significantly during direct shear tests. A conceptual model was proposed to explain the
particle breakage mechanism during shear, at four key phase points representing (1)
maximum compaction, (2) transition from compaction to dilative behavior, (3) maximum
shear stress, and (4) peak test strain. In addition, a loading intensity framework was
adopted to explain the relative roles of normal and shearing stresses on particle
breakage. An increase of fines in soil during shearing was also observed and related to
two sources: coarser grain abrasion and finer particle crushing. The vulnerability of
grains with more anisotropic shapes was also observed. The loading intensity framework
suggested that attrition of particle diameter could be divided into two phases, with a
transitional critical loading intensity that appeared constant for each sand. For Ottawa
sand, abrasion was the primary mechanism observed, causing a significant increase in
Aspect Ratio (AR) and Sphericity (S) for finer grains. For Fiji sand, a transition from
abrasion to attrition was noted, leading to limited sphericity decrease for the largest
particles. Finer particles cushioning larger Fiji sand particles are more prone to
breakage, resulting in increased AR and S. Finally, test results were used to propose a simple
hyperbolic model to predict evolution of the particle size distribution during shear,
for sands. The model was also verified using published data on grain evolution during
shear of a different sand, not employed in its development.
期刊介绍:
Acta Geotechnica is an international journal devoted to the publication and dissemination of basic and applied research in geoengineering – an interdisciplinary field dealing with geomaterials such as soils and rocks. Coverage emphasizes the interplay between geomechanical models and their engineering applications. The journal presents original research papers on fundamental concepts in geomechanics and their novel applications in geoengineering based on experimental, analytical and/or numerical approaches. The main purpose of the journal is to foster understanding of the fundamental mechanisms behind the phenomena and processes in geomaterials, from kilometer-scale problems as they occur in geoscience, and down to the nano-scale, with their potential impact on geoengineering. The journal strives to report and archive progress in the field in a timely manner, presenting research papers, review articles, short notes and letters to the editors.