Journal articles: 'Breakage mechanics'

1

Einav, Itai. "Breakage mechanics—Part I: Theory." Journal of the Mechanics and Physics of Solids 55, no. 6 (June 2007): 1274–97. http://dx.doi.org/10.1016/j.jmps.2006.11.003.

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Wu, Bo, Yu Lin Yan, and Sebastian Münstermann. "Modelling of Chip Breakage in Machining Process with Damage Mechanics Model." Applied Mechanics and Materials 784 (August 2015): 411–18. http://dx.doi.org/10.4028/www.scientific.net/amm.784.411.

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Controlled chip breakage is important for machining process. In order to investigate the chip breakage behaviour in turning process, damage mechanics approach is applied in FE simulation of chip breakage. In this work, an advanced damage mechanics model is implemented for description of the plastic flow and damage behaviour of chip material in simulation. This material model takes the temperature, strain rate as well as state of stress into consideration, which are essential for application in machining processes.

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Einav, Itai. "Breakage mechanics—Part II: Modelling granular materials." Journal of the Mechanics and Physics of Solids 55, no. 6 (June 2007): 1298–320. http://dx.doi.org/10.1016/j.jmps.2006.11.004.

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Jian, Fuxian, Xiaomei Li, and Wanli Guo. "Modeling the Particle Breakage via Breakage Energy during Triaxial Shearing." Journal of Testing and Evaluation 51, no. 2 (October 5, 2022): 20220090. http://dx.doi.org/10.1520/jte20220090.

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Jiang, Hongxiang, Changlong Du, Songyong Liu, and Liping Wang. "Theoretical Modeling of Rock Breakage by Hydraulic and Mechanical Tool." Mathematical Problems in Engineering 2014 (2014): 1–9. http://dx.doi.org/10.1155/2014/895835.

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Rock breakage by coupled mechanical and hydraulic action has been developed over the past several decades, but theoretical study on rock fragmentation by mechanical tool with water pressure assistance was still lacking. The theoretical model of rock breakage by mechanical tool was developed based on the rock fracture mechanics and the solution of Boussinesq’s problem, and it could explain the process of rock fragmentation as well as predicating the peak reacting force. The theoretical model of rock breakage by coupled mechanical and hydraulic action was developed according to the superposition principle of intensity factors at the crack tip, and the reacting force of mechanical tool assisted by hydraulic action could be reduced obviously if the crack with a critical length could be produced by mechanical or hydraulic impact. The experimental results indicated that the peak reacting force could be reduced about 15% assisted by medium water pressure, and quick reduction of reacting force after peak value decreased the specific energy consumption of rock fragmentation by mechanical tool. The crack formation by mechanical or hydraulic impact was the prerequisite to improvement of the ability of combined breakage.

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Nguyen, Giang D., and Itai Einav. "The Energetics of Cataclasis Based on Breakage Mechanics." Pure and Applied Geophysics 166, no. 10-11 (June 30, 2009): 1693–724. http://dx.doi.org/10.1007/s00024-009-0518-x.

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Ravichandar, Krishnamurthy, R. Dennis Vigil, Rodney O. Fox, Stephanie Nachtigall, Andreas Daiss, Michal Vonka, and Michael G. Olsen. "Turbulent droplet breakage in a von Kármán flow cell." Physics of Fluids 34, no. 7 (July 2022): 073319. http://dx.doi.org/10.1063/5.0096395.

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Droplet dispersion in liquid–liquid systems is a crucial step in many unit operations throughout the chemical, food, and pharmaceutic industries, where improper operation causes billions of dollars of loss annually. A theoretical background for the description of droplet breakup has been established, but many assumptions are still unconfirmed by experimental observations. In this investigation, a von Kármán swirling flow device was used to produce homogeneous, low-intensity turbulence suitable for carrying out droplet breakage experiments using optical image analysis. Individual droplets of known, adjustable, and repeatable sizes were introduced into an isotropic turbulent flow field providing novel control over two of the most important factors impacting droplet breakage: turbulence dissipation rate and parent droplet size. Introducing droplets one at a time, large data sets were gathered using canola, safflower, and sesame oils for the droplet phase and water as the continuous phase. Automated image analysis was used to determine breakage time, breakage probability, and child droplet size distribution for various turbulence intensities. Breakage time and breakage probability were observed to increase with increasing parent droplet size, consistent with the classic and widely used Coulaloglou–Tavlarides breakage model (C–T model). The shape of the child drop size distribution function was found to depend upon the size of the parent droplet.

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Alonso, Eduardo E. "Fracture Mechanics and Rockfill Dams." Soils and Rocks 37, no. 1 (January 1, 2014): 3–35. http://dx.doi.org/10.28927/sr.371003.

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Rockfill behavior is dominated by particle breakage, a phenomenon which is analyzed from the perspective offered by the subcritical propagation of cracks within individual particles. Propagation velocity depends on stress concentration in particles as well as on the ambient Relative Humidity (RH). RH controlled oedometer and triaxial tests are reviewed and constitutive models reproducing the main features of observed behavior are outlined. The relevant issue of size effects is then introduced and some rules and possibilities to account for these effects in practice have been given. The Distinct Element Method is also a powerful tool to investigate rockfill behavior. Recent developments are described. The model developed incorporates particle breakage, delayed effects and the action of water. In the final part two real cases are presented: the response of a high rockfill embankment against a four year long rainfall regime and the analysis of Beliche dam. The lecture closes by a general discussion of partial saturation in granular materials ranging from coarse granular aggregates, such as rockfill, to clayey soils in an attempt to provide an integrated overview of water effects in soils.

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Yamazaki, Hidekatsu. "Breakage models: lognormality and intermittency." Journal of Fluid Mechanics 219, no. -1 (October 1990): 181. http://dx.doi.org/10.1017/s0022112090002907.

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Zhang, Yida, and Giuseppe Buscarnera. "Breakage mechanics for granular materials in surface-reactive environments." Journal of the Mechanics and Physics of Solids 112 (March 2018): 89–108. http://dx.doi.org/10.1016/j.jmps.2017.11.008.

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Collins-Craft, Nicholas Anton, Ioannis Stefanou, Jean Sulem, and Itai Einav. "A Cosserat Breakage Mechanics model for brittle granular media." Journal of the Mechanics and Physics of Solids 141 (August 2020): 103975. http://dx.doi.org/10.1016/j.jmps.2020.103975.

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Harmon, John M., Daniel Arthur, and José E. Andrade. "Level set splitting in DEM for modeling breakage mechanics." Computer Methods in Applied Mechanics and Engineering 365 (June 2020): 112961. http://dx.doi.org/10.1016/j.cma.2020.112961.

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13

Kulyakhtin, Sergey. "Application of continuum breakage mechanics to ice rubble modelling." Cold Regions Science and Technology 165 (September 2019): 102797. http://dx.doi.org/10.1016/j.coldregions.2019.102797.

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14

Gan, Deqing, Feng Gao, Yunpeng Zhang, Jinxia Zhang, Fusheng Niu, and Ze Gan. "Effects of the Shape and Size of Irregular Particles on Specific Breakage Energy under Drop Weight Impact." Shock and Vibration 2019 (June 4, 2019): 1–14. http://dx.doi.org/10.1155/2019/2318571.

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Particle shape and size are main factors influencing particle breakage. Single-particle breakage tests were conducted on irregular magnetite ore using modified drop weight impact equipment to analyze the effect of shape and size on specific breakage energy. A method to measure the effective breakage energy is presented. Ore particles with different sphericities and different sizes were broken into several fragments with differing impact energies in the tests. Experimental studies indicate that the shape of particles significantly influences the impact loading mode and breakage progress; the specific breakage energy has an obvious relationship with the sphericity and the initial size. The specific breakage energy decreases with larger initial loading area. The particle needs less specific breakage energy if the shape or placement state is more conducive to tensile fracture. There is an increase in specific breakage energy corresponding to an increase in particle sphericity with fixed initial size range. With the increase in the initial size of the particle, the specific breakage energy decreases with fixed sphericity range, which presents a power function with the exponent −0.5. The comprehensive relationship between specific breakage energy, particle sphericity, and initial size was established, showing that the input power of the crushing machinery and the optimization of crushing technology should be performed with consideration of the influence of particle shape and initial size to reduce specific energy consumption and improve energy efficiency.

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Akiti, Narendra, Yuen Sin Cheong, Karen P. Hapgood, and Devang Khakhar. "A study of wet granule breakage in a breakage-only high-shear mixer." Advanced Powder Technology 31, no. 6 (June 2020): 2438–46. http://dx.doi.org/10.1016/j.apt.2020.04.010.

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16

Wu, Y., and JW Ju. "Elastoplastic damage micromechanics for continuous fiber-reinforced ductile matrix composites with progressive fiber breakage." International Journal of Damage Mechanics 26, no. 1 (July 28, 2016): 4–28. http://dx.doi.org/10.1177/1056789516655671.

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An elastoplastic damage micromechanical framework considering evolutionary fiber breakage is proposed to predict the overall material behaviors of continuous fiber-reinforced composites with ductile matrix under external loading. In the present work, we assume that the overall nonlinear behavior of a composite is primarily attributed to the plastic deformation in the matrix as well as the damage evolution due to fiber breakage. The effective elastoplastic deformations are governed by means of the effective yield surface derived from a representative microstructure with elastic fibers embedded in an elastoplastic matrix material. The matrix behaves elastically or plastically depending on the local stress, and the effective elastoplastic deformation obeys the associative plastic flow rule and isotropic hardening law. In addition, taking advantage of the eigenstrain due to fiber breakage together with a Weibull statistic model, the evolutionary fiber breakage mechanism is effectively predicted. Finally, the overall elastoplastic stress–strain responses are reached under the framework of micromechanics and damage mechanics. Comparisons between the proposed theoretical predictions and experimental data are performed to illustrate the capability of the proposed framework. In particular, the proposed model is employed to investigate the overall uniaxial and axisymmetric elastoplastic stress–strain responses of the continuous fiber-reinforced metal matrix composites. Studies of the initial yield surfaces at various damage levels are conducted as well.

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Russell, Alexander, Rok Šibanc, Rok Dreu, and Peter Müller. "Mechanics of Pharmaceutical Pellets—Constitutive Properties, Deformation, and Breakage Behavior." Journal of Pharmaceutical Sciences 107, no. 2 (February 2018): 571–86. http://dx.doi.org/10.1016/j.xphs.2017.08.022.

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18

Mullier, M. A., J. P. K. Seville, and M. J. Adams. "A fracture mechanics approach to the breakage of particle agglomerates." Chemical Engineering Science 42, no. 4 (January 1987): 667–77. http://dx.doi.org/10.1016/0009-2509(87)80027-1.

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19

Einav, Itai. "Fracture propagation in brittle granular matter." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 463, no. 2087 (August 28, 2007): 3021–35. http://dx.doi.org/10.1098/rspa.2007.1898.

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It is nearly a century since Alan Arnold Griffith developed his energy criterion for the fracture propagation of cracks in ‘near-continuous’ solids. Needless to say that his celebrated work has revolutionized the world of material science. In a very succinct way, Griffith connected between three important aspects of the fracture process: (i) the material, (ii) the stress level, and (iii) the geometry of the crack. Nothing similar was developed for brittle granular matter, although in these materials fracture propagates in the sense of comminution. Recently, I have developed an energy theory, called breakage mechanics, based on the concept of breakage. However, the analogy between the mechanics of breakage and fracture is missing. Here I establish this relation using energy principles and derive a critical comminution pressure for brittle granular materials. This critical pressure is surprisingly complementary to Griffith's critical tensile stress for near-continuous materials. This step enables for the first time to apply the principles of fracture mechanics to all disciplines dealing with confined particles comminution such as geophysics, geology, geotechnical engineering, mineral processing, agriculture and food industry, pharmaceutics and powder technology.

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Xu, Liang-Jie, Ren Wang, Dong-Sheng Xu, Xin-Zhi Wang, Qing-Shan Meng, and Chang-Qi Zhu. "Review of Particle Breakage Measurement Methods for Calcareous Sand." Advances in Civil Engineering 2022 (May 17, 2022): 1–13. http://dx.doi.org/10.1155/2022/6477197.

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In order to better understand the particle breakage mechanics and characterization methods of calcareous sand, the particle breakage characteristics of calcareous sand in one-dimensional compression tests, isotropic compression tests, triaxial shear tests, and ring shear tests are reviewed and analyzed. The results show that the mechanism of shear crushing is essentially different from compression crushing. Compared with one-dimensional compression, it is easier to break calcareous sand under triaxial shear. In the shearing process, the particle breakage of calcareous sand will not continue indefinitely. The gradation tends to be stable and controlled by confining pressure and shear strain. The characteristic particle size measurement method for particle breakage is simple and has limitations. The description method using the particle size distribution curve is more comprehensive, but it is impossible to compare the crushing degree of particle with different particle sizes, and a suitable measurement method needs to be proposed.

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21

Ruiz, María P., António J. V. Pontes, and Leandro N. Ludueña. "Isolation of hydrodynamic parameters for the fibre length attrition in injection-moulded short-fibre polymer composites." Journal of Reinforced Plastics and Composites 40, no. 13-14 (April 7, 2021): 505–17. http://dx.doi.org/10.1177/0731684420983899.

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A comprehensive study of the fibre breakage mechanisms during mould filling in injection moulding of short-fibre polymer composites requires the isolation of the main parameters promoting fibre length attrition. In this work, hydrodynamic parameters such as injection flow rate and residence time in the range of injection moulding were isolated, and their effect on fibre length attrition was studied. Fibre breakage was quantified by means of a capillary rheometer attached to an injection moulding machine minimising fibre-equipment interactions. Fibre breakage increased linearly as a function of injection flow rate in the range of 30–120 cm3.s−1. It was also found that residence time in the order of milliseconds had a significant effect on fibre breakage. The results shown that longer fibres had less breakage probability, which contradicts the buckling failure theory for brittle fibres in a simple shear flow. This result was attributed to the similar rotation period of the fibres in comparison with the test residence times.

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Huang, Ping Lu, and Cong Xin Chen. "Study on Stability of Consequent Rock Slope by Simulation Experiment." Advanced Materials Research 261-263 (May 2011): 1470–74. http://dx.doi.org/10.4028/www.scientific.net/amr.261-263.1470.

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Based on similarity theory, the geologic mechanics model is established and to be used for studying distortion and breakage mechanism of consequent rock slope. The paper introduces the design and process of the experimentation. Through experimentation of a slope model, the stability of a slope is studied. After analyzing the phenomenon and data of the experimentation, it is found that the major deformation model is slippage. The mode of breakage is sliding and fracturing. The process of slippage is graded. The more hinder the position of coast is, the smaller the obliquity of rip face is. The deformation and breakage of bedding slope firstly arises at the dig face near the earth's surface.

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Li, Hong Ru, Fei Feng, and Qing Wang. "Application of Structural Loess Binary-Medium Mode in Localization Shear Band." Applied Mechanics and Materials 204-208 (October 2012): 825–32. http://dx.doi.org/10.4028/www.scientific.net/amm.204-208.825.

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Based on the theory of breakage mechanics,the structural loess are conceptualized as binary －medium model consisting of bonding brick and frictional band. Shear band is structural loess’ breakage, localization band sprout and development is dynamic process that bonding brick is translating into frictional band.Application of double parameter breakage ratio binary-medium mode of structural loess,simulated the process of structural loess localization band sprouting and expanding with the numerical simulations method,studied localization shear band shape、speciality and law under different disfigurement project,found that the strain localization on a shear band of structural soil at originally is some sets discontinuous little local breakage area step by step developed、 connected and formed the shape of whole destruct with the external load increased,appeared dilatation softening phenomena under the especial disfigurement. Combining binary-medium mode with general finite element,solved the question of localization shear band softening,visual reappeared the course of the local shear band germination and progress.

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Si, Hu, Xiao Hong Li, and Yan Ming Xie. "Damage Analysis and Simulation of Rock under High Pressure Waterjet." Key Engineering Materials 462-463 (January 2011): 774–79. http://dx.doi.org/10.4028/www.scientific.net/kem.462-463.774.

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The high pressure waterjet is widely applied for mine industry, mechanical manufacture, environmental engineering, and medicine field due to its particular characteristic. Recently, the application of high pressure waterjet for gas drainage in mine has been receiving increasing attention with the development of exploitative technology. The micro-damage mechanism of coal under high pressure water jet is key to drain gas effectively. Based on damage mechanics and rock dynamics, the paper analyzed the micro-structure deformation and damage of rock and the impulsive effect under high pressure water jet and developed the dynamic model. Further, on the assumption of that rock was homogeneous and isotropic, a computational model was established based on the Arbitrary Lagrangian Eulerian (ALE) fluid-solid coupling penalty function method. The rock damage under high pressure water jet was simulated by the dynamic contact method. The results showed that the damage and breakage of ruck was mainly attributed to impacting effect and was characterized by local effect, and the evolvement of rock breakage went through three stages and the figure of rock breakage trended a funnel. On the whole, numerical results agreed with experimental results.

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Sasmal, C. "Effect of micelle breaking rate and wall slip on unsteady motion past a sphere translating steadily in wormlike micellar solutions." Physics of Fluids 34, no. 7 (July 2022): 073110. http://dx.doi.org/10.1063/5.0096602.

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Many prior experimental studies have found the existence of an unsteady or fluctuating flow field around a solid sphere when falling in wormlike micellar solutions. Based on the two-species Vasquez–Cook–McKinley constitutive model for micelles, a recent numerical study shows that the breakage of long micelles downstream of the translating sphere causes this unsteady motion [C. Sasmal, “Unsteady motion past a sphere translating steadily in wormlike micellar solutions: A numerical analysis,” J. Fluid Mech. 912, A52, (2021)]. This numerical study further shows that the micelle breakage rate and wall slip can strongly influence this phenomenon. In particular, we find that the onset of this unsteady motion is delayed to higher values of the Weissenberg number as the micelle breakage rate decreases, or in other words, micelles become hard to break. Additionally, we observe that at some values of the micelle breakage rate, again, a transition in the flow field from unsteady to steady occurs at high Weissenberg numbers. Therefore, there is a window of the Weissenberg number present to observe this unsteady motion past the translating sphere. On the other hand, we show that the presence of wall slip on the sphere surface suppresses this unsteady motion past the translating sphere, and a probable explanation is also provided for the same.

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Bilisik, Kadir, Nesrin S. Karaduman, and Erdal Sapanci. "Flexural characterization of 3D prepreg/stitched carbon/epoxy/multiwalled carbon nanotube preforms and composites." Journal of Composite Materials 53, no. 5 (July 13, 2018): 563–77. http://dx.doi.org/10.1177/0021998318787861.

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The effect of through-the-thickness stitching and incorporation of multiwalled carbon nanotubes (MWCNTs) on the flexural properties of three-dimensional (3D) carbon/epoxy composites was studied. The flexural strength of the carbon twill fabric composites was improved by stitching due largely to delamination suppression, whereas stitching negatively influenced the flexural strength of the carbon satin fabric composites due to stitch-induced irregularities and fiber breakages. The failure mode of the unstitched base (without MWCNTs) and unstitched nano-added structures involved fiber breakage, matrix cracking, and delamination, while the stitched base and stitched nano-added samples exhibited lateral matrix cracking, multiple warp, and stitch yarn breakages with less delamination compared with unstitched structures. The results showed that both stitching and the incorporation of MWCNTs improved the out-of-plane failure properties due largely to restricted delamination. Therefore, stitching and MWCNTs can effectively be used to increase the damage tolerance of carbon fiber/epoxy composite laminates.

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Jiang, Hongxiang, Zhiyuan Cai, Ouguo Wang, and Deguang Meng. "Experimental and Numerical Investigation of Hard Rock Breakage by Indenter Impact." Shock and Vibration 2020 (May 18, 2020): 1–12. http://dx.doi.org/10.1155/2020/2747830.

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To investigate the effect of indenter shape, impact energy, and impact velocity on the rock breakage performance, a test device for rock fragmentation by indenter impact was developed to obtain the rock breakage volume, depth, and area under different impact conditions. By comparing the rock breakage volume, depth, area, and specific energy consumption, the results show that indenter shape has a greater influence on the rock breakage performance than that of the impact velocity with the same impact energy, and impact energy plays a decisive role in rock breakage performance with an identical indenter shape and impact velocity. For the lowest to highest specific energy consumption, the order of indenter shape is cusp-conical, warhead, hemispherical, spherical-arc, and flat-top under the same impact energy and velocity, but the cusp-conical indenter is damaged after several impacts. The rock breakage volume, depth, and area all increase with the increase in impact energy, but the effect of the impact velocity could be ignored under the same impact energy. In addition, the rock breakage features of the numerical simulation and experiments are similar, which show that the crushing zone close to the indenter impact point is mainly caused by the high compressive stress, and then radial cracks are caused by the accumulative energy release. The findings of this study will contribute to progress in the performance and efficiency for percussive rock drilling.

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Liao, Y., R. Oertel, S. Kriebitzsch, F. Schlegel, and D. Lucas. "A discrete population balance equation for binary breakage." International Journal for Numerical Methods in Fluids 87, no. 4 (February 14, 2018): 202–15. http://dx.doi.org/10.1002/fld.4491.

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Cai, Guo-Qing, Cheng-Gang Zhao, and Xiao-Ming Qin. "Structural bonding-breakage constitutive model for natural unsaturated clayey soils." Acta Mechanica Sinica 26, no. 6 (September 28, 2010): 931–39. http://dx.doi.org/10.1007/s10409-010-0375-y.

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Dukino, R. D., M. V. Swain, and C. E. Loo. "A simple contact and fracture mechanics approach to tumble drum breakage." International Journal of Mineral Processing 59, no. 2 (May 2000): 175–83. http://dx.doi.org/10.1016/s0301-7516(99)00031-9.

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Kumar, Rajnish, and S. K. Choudhury. "Prevention of wire breakage in wire EDM." International Journal of Machining and Machinability of Materials 9, no. 1/2 (2011): 86. http://dx.doi.org/10.1504/ijmmm.2011.038162.

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Le Bouteiller, Caroline, and Mohamed Naaim. "Aggregate breakage under dynamic loading." Granular Matter 13, no. 4 (December 5, 2010): 385–93. http://dx.doi.org/10.1007/s10035-010-0235-2.

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Stadnik, Alexander, Sergii Podlesny, Svitlana Kaporovych, and Oleksii Kabatskyi. "Spatial transportation of the beam on a bifilar fastening." FME Transactions 50, no. 3 (2022): 548–60. http://dx.doi.org/10.5937/fme2203548s.

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The complex problem of the spatial motion of the "trolley-beam" mechanical system is investigated. Three stages are considered: 1) movement of the beam on a bifilar suspension to the movable trolley; 2) movement of the beam after the breakage of one branch of the suspension; 3) movement of the beam after the breakage of the second branch of the suspension. The study was carried out by creating mathematical models for each stage of the system movement and then conducting a numerical experiment using computer algebra. The tension of the ropes is calculated at the first and second stages of the system movement. Their extreme values are determined. The obtained results will be used in the further study of the system to reduce the tension of the rope and oscillation amplitude and to prevent accidents.

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Zhang, Yong Bo. "Experimental Research on Instability Activation Mechanism of Old Goaf Overburden Rock." Advanced Materials Research 250-253 (May 2011): 1426–32. http://dx.doi.org/10.4028/www.scientific.net/amr.250-253.1426.

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Taking the 2204 working face of Xinzhi Colliery in Huozhou as the background, through experiment of analog simulation, analyze the structure type of old goaf overburden rock breakage, instability activation mechanism of overburden rock and instability form and condition for stability of voussoir beam of old goaf. As the result, after mining and breakage, the rock mass structure of old goaf and overburden rock can be divided four types. This secondary rock structure has an important effect on old goaf activation. The existence form will decide the basic characteristic of old goaf activation. Through the mechanics analysis on voussoir beam of old goaf , it is obtained that instability due to sliding mainly depend upon the physical mechanics characteristic of key block and sideward rock, W/T value, and additional load of building on surface and so on. Rotational instability is related to the physical mechanics characteristic of key block and sideward rock and thick and length ratio h/l of the hanging rock

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Kannan, P. R., K. Periasamy, P. Pravin, and J. R. Vinod Kumaar. "An experimental investigation of wire breakage and performance optimisation of WEDM process on machining of recycled aluminium alloy metal matrix composite." Materials Science-Poland 40, no. 3 (December 1, 2022): 12–26. http://dx.doi.org/10.2478/msp-2022-0030.

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Abstract In this research, a novel aluminium metal matrix composite (AMMC) was developed using recycled aluminium alloy as a matrix with 5% alumina as reinforcement. The machining experiments were conducted by varying the input parameters such as voltage (V s ), wire feed rate (F w ), current (I p ), pulse on time (ON T ) and pulse off time (OFF T ), on wire breakage. The effect of voltage level and wire breakage frequency was analysed. The parameter combinations for machining the slot of size 5 mm width and 10 mm height with high machining rate (MR) and less surface roughness (R a ) were analysed using the CRiteria Importance Through Intercriteria Correlation (CRITIC) and simple additive weighting (SAW) methods. The wire breakage frequency is lesser at minimum peak current. The optimal parameter combination for higher MR and lower R a is found to be at 30 V, 7 mm/min, 30 A, 120 μs (ON T ) and 70 μs (OFF T ). Analysis of variance (ANOVA) is performed to understand the significant factors affecting the WEDM process. ANOVA results predict that wire feed rate and voltage contribute 47.82% and 21.23%, respectively, to MR; and pulse on time shows a 23.06% influence on surface roughness. Scanning electron microscopy (SEM) was used to ascertain the pattern of wire breakage in WEDM, and based on the results obtained from employing this technique, it is inferred that the erosion and breakage of the wire are not instantaneous and that a cone shape is formed on the either portion of the wire.

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Pazmiño, Sebastián A., Alex X. Jerves, Jelke Dijkstra, David A. Medina, and Hans Petter Jostad. "A generalized 3DLS-DEM scheme for grain breakage." Computer Methods in Applied Mechanics and Engineering 399 (September 2022): 115383. http://dx.doi.org/10.1016/j.cma.2022.115383.

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Dilsaver, Matthew R., Pan Chen, Trey A. Thompson, Traci Reusser, Richik N. Mukherjee, John Oakey, and Daniel L. Levy. "Emerin induces nuclear breakage in Xenopus extract and early embryos." Molecular Biology of the Cell 29, no. 26 (December 15, 2018): 3155–67. http://dx.doi.org/10.1091/mbc.e18-05-0277.

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Emerin is an inner nuclear membrane protein often mutated in Emery–Dreifuss muscular dystrophy. Because emerin has diverse roles in nuclear mechanics, cytoskeletal organization, and gene expression, it has been difficult to elucidate its contribution to nuclear structure and disease pathology. In this study, we investigated emerin’s impact on nuclei assembled in Xenopus laevis egg extract, a simplified biochemical system that lacks potentially confounding cellular factors and activities. Notably, these extracts are transcriptionally inert and lack endogenous emerin and filamentous actin. Strikingly, emerin caused rupture of egg extract nuclei, dependent on the application of shear force. In egg extract, emerin localized to nonnuclear cytoplasmic membranes, and nuclear rupture was rescued by targeting emerin to the nucleus, disrupting its membrane association, or assembling nuclei with lamin A. Furthermore, emerin induced breakage of nuclei in early-stage X. laevis embryo extracts, and embryos microinjected with emerin were inviable, with ruptured nuclei. We propose that cytoplasmic membrane localization of emerin leads to rupture of nuclei that are more sensitive to mechanical perturbation, findings that may be relevant to early development and certain laminopathies.

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Ravshanov, Hamrokul, Farmon Mamatov, Odil Primov, Shakhnoza Khazratkulova, and Dilshod Baratov. "Study on technological properties of winter wheat soils." E3S Web of Conferences 304 (2021): 03010. http://dx.doi.org/10.1051/e3sconf/202130403010.

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The aim of the study is to study and analyze the physical, mechanical and technological properties of soils from under winter grain crops in the hot climate of Uzbekistan. The results of determining the moisture content, density, hardness and resistance to various deformations of soils after harvesting winter wheat are presented. The basic principles and methods of classical mechanics, mathematical analysis and statistics were used in this study. Studies have found that, in the layer 0-30, the soil moisture for ten days after harvesting winter cereals decreases by 12.1-16.3%, and the soil hardness increases by 10.7-16.4% and are 3.22-5.14 MPa. At the same time, at an average humidity of 12-14%, the resistance of the soil to breakage and torsion, respectively, is 1.3-1.8 and 1.0-1.1 times higher than the resistance of the soil to shear. The resistance of the soil to shear is 87.9 kPa, and to breakage and torsion-69.7 and 78.6 kPa, respectively.

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Saberi, Miad, Charles-Darwin Annan, and Jean-Marie Konrad. "Constitutive Modeling of Gravelly Soil–Structure Interface Considering Particle Breakage." Journal of Engineering Mechanics 143, no. 8 (August 2017): 04017044. http://dx.doi.org/10.1061/(asce)em.1943-7889.0001246.

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Guo, Wan-Li, Zheng-Yin Cai, Ying-Li Wu, and Zhi-Zhou Geng. "Estimations of Three Characteristic Stress Ratios for Rockfill Material Considering Particle Breakage." Acta Mechanica Solida Sinica 32, no. 2 (January 29, 2019): 215–29. http://dx.doi.org/10.1007/s10338-019-00074-x.

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Ma, Zhigang, Shuaifeng Wu, and Ran Wei. "Extrapolation-Based Scale Effect Model for Granular Heap Modulus." Advances in Civil Engineering 2023 (January 23, 2023): 1–14. http://dx.doi.org/10.1155/2023/5841804.

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The numerical analysis was used to predict the rockfill dam displacement, and the model parameters were calibrated using the triaxial experiments on scale-down rockfill samples. Due to the scale effect of rockfill material, the displacements were usually underestimated in the design phase. This study focused on the scale effect of rockfill material and an extrapolation model was proposed to extrapolate the prototype modulus from the laboratory modulus. By conducting confined compression experiments, the size effect was investigated using ball heaps. Based on the experimental findings, considering a granular heap as a cumulative particle structure, the structural mechanics approach was introduced to establish the size effect model. Then, the boundary constrain effect model was speculated using the elastic mechanics analysis. By conducting the confined experiments on ball heaps, the modulus variation with particle breakage was investigated and the breakage effect model was established consequently. Finally, via combining the effects from the size, boundary constrain, and particle breakage, a scale effect model was established for extrapolating prototype modulus from the laboratory modulus. The proposed model was evaluated through numerical analysis of an actual dam. The experimental results revealed that the compressive modulus decreased as the initial void ratio increased; under the same initial void ratio, the compressive modulus decreased as the ratio of the specimen width to particle size increased; the compressive modulus decreased as the particle breakage increased. The numerical analysis results showed that prediction accuracy for rockfill dam displacement was improved by 8%–10%. The proposed model represents a new approach for investigating the scale effect of rockfill material, which could be adopted by engineers to improve the prediction of rockfill dam displacement.

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Nguyen, Giang D., and Itai Einav. "Nonlocal regularisation of a model based on breakage mechanics for granular materials." International Journal of Solids and Structures 47, no. 10 (May 2010): 1350–60. http://dx.doi.org/10.1016/j.ijsolstr.2010.01.020.

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Das, Arghya, Giang D. Nguyen, and Itai Einav. "The propagation of compaction bands in porous rocks based on breakage mechanics." Journal of Geophysical Research: Solid Earth 118, no. 5 (May 2013): 2049–66. http://dx.doi.org/10.1002/jgrb.50193.

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Liu, Shuang, Qing Wen Ren, and Chen Lu Zhou. "Numerical Research on the Gravity Dam Deep Anti-Sliding with Engineering Mechanics Based on Damage Theory." Advanced Materials Research 910 (March 2014): 289–96. http://dx.doi.org/10.4028/www.scientific.net/amr.910.289.

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Currently, researches on the gravity dam deep and shallow anti-sliding stability mainly focus on the analysis method and instability criterion, while the studies on specifically test the breakage of gravity dams due to weakening foundation rock mass and structural planes under loading are rare. Based on damage mechanics theory, this paper established a numerical model that analyzed the damage failure process of dam foundation rock mass. Taking two typical gravity dam models as the study objects, the damage processes of the dam foundations were simulated dynamically. Additionally, a comparison with other two traditional methods further validated the correctness and feasibility of the numerical model. In sum, the study findings point out that the numerical model is not only applicable to the study of the breakage mechanism of dam foundation rock mass, but also can be used as a new method to analyze problems related to deep anti-sliding stability of gravity dams.

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Wang, Jiajun, Linqi Huang, Xibing Li, Yangchun Wu, and Huilin Liu. "Effect of Particle Size Distribution on the Dynamic Mechanical Properties and Fractal Characteristics of Cemented Rock Strata." Mathematics 10, no. 12 (June 15, 2022): 2078. http://dx.doi.org/10.3390/math10122078.

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To investigate the dynamic mechanics and post-failure characteristics of fault-cemented rock strata, broken rock particles were reshaped to obtain cemented rock samples with various particle size distributions (PSDs). Split Hopkinson pressure bar (SHPB) dynamic impact tests were performed on the cemented rock samples under different strain rates. The test results show that plastic deformation occurs in the cemented rock sample as a result of its porous structure. Therefore, there is no linear phase in the dynamic stress–strain curves. With an increase in the Talbot index and mixture type, more large particles were contained inside the cemented rock sample, and the dynamic strength gradually increased. A power function can effectively describe the relationship between the strain rate and dynamic strength for various Talbot indices. After dynamic impact, the fragments of the cemented rock samples exhibit evident fractal laws, and the breakage of the samples includes breakage of the original rock particle itself and breakage between the rock particles and cementations. The breakage ratio and fractal dimension both decrease with the increase in the number of mixture type and Talbot index but increase with the increase in strain rate. It is worth noting that the breakage ratio and fractal dimension have a linear relationship regardless of the PSD or strain. The relationship between the dynamic strength and fractal dimension has different response laws for the PSD and strain rate effects. The dynamic strength is negatively linearly related to the fractal dimension under the PSD effect but positively linearly related to the fractal dimension under the strain rate effect. This research work can provide foundation support for investigating the instability mechanism of fault cemented rock strata under dynamic stress.

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Einav, Itai. "Soil mechanics: breaking ground." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 365, no. 1861 (September 13, 2007): 2985–3002. http://dx.doi.org/10.1098/rsta.2007.0009.

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In soil mechanics, student's models are classified as simple models that teach us unexplained elements of behaviour; an example is the Cam clay constitutive models of critical state soil mechanics (CSSM). ‘Engineer's models’ are models that elaborate the theory to fit more behavioural trends; this is usually done by adding fitting parameters to the student's models. Can currently unexplained behavioural trends of soil be explained without adding fitting parameters to CSSM models, by developing alternative student's models based on modern theories? Here I apply an alternative theory to CSSM, called ‘breakage mechanics’, and develop a simple student's model for sand. Its unique and distinctive feature is the use of an energy balance equation that connects grain size reduction to consumption of energy, which enables us to predict how grain size distribution (gsd) evolves—an unprecedented capability in constitutive modelling. With only four parameters, the model is physically clarifying what CSSM cannot for sand: the dependency of yielding and critical state on the initial gsd and void ratio.

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Golovkin, Valery V., Oksana M. Batishcheva, and Valery A. Papshev. "Study on the Ultrasonic Vibration Impact on the Performance of Taps when Thread Cutting in Workpieces Made of Difficult-to-Machine Materials." Key Engineering Materials 910 (February 15, 2022): 109–14. http://dx.doi.org/10.4028/p-78n7b4.

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Materials with high mechanical properties are increasingly used in modern mechanical engineering in order to enhance the performance and service life of critical parts. Since these are difficult-to-machine materials, serious problems can arise due to low tool life or even with its breakage during mechanical processing. The greatest difficulties are connected with the processing of small-diameter holes, since, for example, breakage of drills or taps occurs when drilling and tapping. It should also be noted that when threading in workpieces made of difficult-to-machine materials, the cutting teeth of the taps are chipped. One of the possible solutions to this problem is the use of physicochemical processing methods, in particular, the transmission of forced ultrasonic oscillations to the tap.

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Liu, Huabei, and Degao Zou. "Associated Generalized Plasticity Framework for Modeling Gravelly Soils Considering Particle Breakage." Journal of Engineering Mechanics 139, no. 5 (May 2013): 606–15. http://dx.doi.org/10.1061/(asce)em.1943-7889.0000513.

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Oladele, Temitope, Lawrence Bbosa, and Dion Weatherley. "Textural and Mineralogical Controls on Rock Strength Elucidated Using a Discrete Element Method Numerical Laboratory." Minerals 11, no. 9 (September 18, 2021): 1015. http://dx.doi.org/10.3390/min11091015.

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Numerical modelling techniques such as the discrete element method are now well established and extensively used in many applications including solid earth geoscience, materials science, geotechnical engineering and rock mechanics. The potential for this technique in understanding comminution mechanisms has been identified as highly promising. This work utilizes the discrete element method as a numerical laboratory to conduct investigations relevant to comminution that would otherwise be costly or time-consuming to perform in the field or laboratory. A benchmark numerical model for impact breakage of rock specimens is first established and validated against results of controlled laboratory experiments. Thereafter, the model is utilized to systematically investigate the potential dependency of ore breakage properties upon the prevalence of pre-existing fractures, as well as the mineralogical composition of the ore. These numerical experiments serve to highlight the potential for quantitatively relating the mechanical response of ore to its textural and mineralogical characteristics. Tandem utilization of numerical and laboratory experimentation to formulate and test hypotheses is a promising avenue to illuminate such relationships.

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Buscarnera, Giuseppe, Yanni Chen, José Lizárraga, and Ruiguo Zhang. "Multi‐scale simulation of rock compaction through breakage models with microstructure evolution." Proceedings of the International Association of Hydrological Sciences 382 (April 22, 2020): 421–25. http://dx.doi.org/10.5194/piahs-382-421-2020.

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Abstract. Regional subsidence due to fluid depletion includes the interaction among multiple physical processes. Specifically, rock compaction is governed by coupled hydro-mechanical feedbacks involving fluid flow, effective stress change and pore collapse. Although poroelastic models are often used to explain the delay between depletion and subsidence, recent evidence indicates that inelastic effects could alter the rock microstructure, thus exacerbating coupling effects. Here, a constitutive law built within the framework of Breakage Mechanics is proposed to account for the inherent connection between rock microstructure, hydraulic conductivity, and pore compaction. Furthermore, it is embedded into a 1-D hydromechanical coupled finite element analysis (FEA) to explore the effects of micro-structure rearrangement on the development of reservoir compaction. Numerical examples with the proposed model are compared with simulations under constant hydraulic conductivity to illustrate the model capability to capture the non-linear processes of reservoir compaction induced by fluid depletion.

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Journal articles on the topic 'Breakage mechanics'

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