Bibliografias temáticas / Dynamic cracking

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Literatura científica selecionada sobre o tema "Dynamic cracking"

Autor: Grafiati
Publicado: 24 de agosto de 2024

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Artigos de revistas sobre o assunto "Dynamic cracking"

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Carpinteri, A., G. Lacidogna, M. Corrado e E. Di Battista. "Cracking and crackling in concrete-like materials: A dynamic energy balance". Engineering Fracture Mechanics 155 (abril de 2016): 130–44. http://dx.doi.org/10.1016/j.engfracmech.2016.01.013.

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Krupp, Ulrich. "Dynamic Embrittlement - Diffusion-Induced Intergranular Cracking". Defect and Diffusion Forum 258-260 (outubro de 2006): 192–98. http://dx.doi.org/10.4028/www.scientific.net/ddf.258-260.192.

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The present paper is about dynamic embrittlement as a generic damage mechanism. It involves grain-boundary diffusion of an embrittling species at elevated temperatures under the influence of mechanical stress. The embrittling species, either coming from the material itself or from the environment, reduces the grain-boundary cohesion and, hence, causes time-dependent intergranular fracture. Evidence of the technical significance of dynamic embrittlement is given by two examples, stress-relief cracking in steels and hold-time cracking during low-cycle-fatigue loading of nickel-base superalloys. There is an obvious relationship between the grain-boundary structure and the local susceptibility to dynamic embrittlement. This was proven by mechanical experiments on bicrystals and grain-boundary-engineering-type-processed specimens.
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Islam, M. R., S. A. Kalevela, J. A. Rivera e T. B. Rashid. "Dynamic Modulus and Field Performance of Cold-in-Place Recycled Asphalt Pavement". Journal of Engineering Sciences 6, n.º 2 (2019): b1—b7. http://dx.doi.org/10.21272/10.21272/jes.2019.6(2).b1.

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This study investigates the dynamic modulus of cold-in-place recycling (CIR) asphalt material and its performance using pavement performance data and laboratory dynamic modulus testing. Colorado Department of Transportation (CDOT) has 37 projects with over 8 million square yards using CIR materials. Sites from ten projects were selected to monitor the performances and collect samples for laboratory testing. Dynamic modulus testing on the CIR cores was conducted by the CDOT. Results show measured distresses of CIR rehabilitation techniques are mostly below the threshold values during the service period. International Roughness Index, rutting, and transverse cracking never exceeded the threshold values during the studied period. Only two CIR pavements exceeded the threshold values for fatigue cracking after 8-10 years of service. Measured distresses of CIR rehabilitation techniques are similar to conventional pavements based on engineering judgment. The laboratory dynamic modulus test results show CIR has about 50 % less dynamic modulus compared to the traditional asphalt mixture. Keywords: asphalt pavement, cold-in-place recycling, dynamic modulus, fatigue cracking, transverse cracking.
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Wang, Yongfei, Junru Li, Zhenyu Wu, Jiankang Chen, Chuan Yin e Kang Bian. "Dynamic Risk Evaluation and Early Warning of Crest Cracking for High Earth-Rockfill Dams through Bayesian Parameter Updating". Applied Sciences 10, n.º 21 (29 de outubro de 2020): 7627. http://dx.doi.org/10.3390/app10217627.

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Crest cracking is one of the most common damage types for high earth-rockfill dams. Cracking risk of dam crest is closely related to the duration of abnormal deformation state. In this paper, a methodology for dynamic risk evaluation and early warning of crest cracking for high earth-rockfill dams is proposed and mainly consists of: (a) The discrimination of abnormal deformation state related to crest cracking, which is implemented by comparing the crest settlement inclination with the threshold value. (b) Computation of crest cracking probability and estimation of cracking time. The exponential distribution is adopted to represent the probability distribution of the duration TAS of abnormal state before crest cracking. Then the crest cracking probability in a given time can be computed by integration with respect to TAS. Inversely, the cracking time corresponding to a given probability can be estimated. (c) Determination of the values of probability adopted to early warn crest cracking, which are suggested to be selected by statistical analysis of the calculated probabilities at the observed cracking times. (d) Bayesian estimation and updating of probability distribution of the parameter λ in the PDF of TAS, according to observed durations of abnormal state before crest cracking. The methodology is illustrated and verified by the case study for an actual earth-rockfill dam, of which crest cracking and recracking events were observed during the periods of high reservoir level. According to the observed values of TAS, the probability distribution for λ is progressively updated and the dispersion of the distributions of λ gradually decreases. The crest cracking probability increases with the duration of abnormal state and the width of confidence interval of the estimated cracking probability progressively contracts with the updating of the distribution for λ. Finally, the early warning of crest cracking for the dam is investigated by estimating the lower limit of cracking time. It is shown that early warning of crest cracking can be issued from at least 20 days ahead of the occurrence of crest cracking event. The idea of using duration of abnormal state of crest settlement to evaluate crest cracking risk of the earth-rockfill dam in this paper may be applicable to other dams.
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Darowicki, K., J. Orlikowski e A. Arutunow. "Detection of stress corrosion cracking dynamics by dynamic electrochemical impedance spectroscopy". Corrosion Engineering, Science and Technology 39, n.º 3 (setembro de 2004): 255–60. http://dx.doi.org/10.1179/147842204x2844.

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Zhao, Chuanyu, Chaowei Liu e Qiang Xu. "Dynamic Scheduling for Ethylene Cracking Furnace System". Industrial & Engineering Chemistry Research 50, n.º 21 (2 de novembro de 2011): 12026–40. http://dx.doi.org/10.1021/ie200318p.

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Zhang, Yiming, e Xiaoying Zhuang. "Cracking elements method for dynamic brittle fracture". Theoretical and Applied Fracture Mechanics 102 (agosto de 2019): 1–9. http://dx.doi.org/10.1016/j.tafmec.2018.09.015.

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Shaheen-Mualim, Merna, Anna Gleizer e Dov Sherman. "Dynamic stress corrosion cracking in silicon crystal". International Journal of Fracture 219, n.º 2 (16 de agosto de 2019): 161–74. http://dx.doi.org/10.1007/s10704-019-00387-5.

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Cui, Y. "Dynamic matrix cracking in fiber reinforced ceramics". Journal of the Mechanics and Physics of Solids 43, n.º 12 (dezembro de 1995): 1875–86. http://dx.doi.org/10.1016/0022-5096(95)00060-v.

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Li, Yong, Haoyue Sui, Ruilin Hu, Fangpeng Cui, Yidi Qiu e Wei Gao. "Study on the Effect of Rock Mass Structure on CO2 Transient Fissure Excavation". Applied Sciences 13, n.º 23 (25 de novembro de 2023): 12666. http://dx.doi.org/10.3390/app132312666.

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As a new rock breaking method, CO2 transient cracking has been widely used in rock excavation projects in recent years. However, in the actual construction process, there are often situations where the fracturing effect varies due to different rock mass structures. Through theoretical analysis and on-site cracking tests, this article studies the effect of CO2 transient cracking under the control of different rock mass structures. The results show that: (1) the dynamic compressive strength of rock directly determines the number and range of dynamic impact fractures; the original fractures of rock mass and those caused by dynamic impact in the first stage jointly determine the effect of high-pressure gas expansion in the second stage. (2) The arrangement of holes along the strata is conducive to the action of high-pressure expanding gas along the soft structural plane in the rock mass, which is conducive to the fracturing of the rock mass; the amount of crack formation is small, but the influence range is large. (3) The cracking effect of carbon dioxide transient cracking applied to massive rock mass is better than that of monolithic rock mass, while the cracking effect of layered rock mass with soil interlayer is poor. The research results are of great significance for improving the effectiveness of carbon dioxide transient-induced cracking excavation and guiding actual construction.
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Mais fontes

Teses / dissertações sobre o assunto "Dynamic cracking"

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Crump, Timothy. "Modelling dynamic cracking of graphite". Thesis, University of Manchester, 2018. https://www.research.manchester.ac.uk/portal/en/theses/modelling-dynamic-cracking-of-graphite(71e81d6f-e712-458c-aa48-0a256749258a).html.

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Advances in dynamic fracture modelling have become more frequent due to increases in computer speed, meaning that its application to industrial problems has become viable. From this, the author has reviewed current literature in terms of graphite material properties, structural dynamics, fracture mechanics and modelling methodologies to be able to address operational issues related to the ageing of Advanced Gas-cooled Reactor (AGR) cores. In particular, the experimentally observed Prompt Secondary Cracking (PSC) of graphite moderator bricks which has yet to be observed within operational reactors, with the objective of supporting their plant life extension. A method known as eXtended Finite Element Method with Cohesive Zones (XCZM) was developed within Code_Aster open-source FEM software. This enabled the incorporation of velocity toughening, irradiation-induced material degradation effects and multiple 3D dynamic crack initiations, propagations and arrests into a single model, which covers the major known attributes of the PSC mechanism. Whilst developing XCZM, several publications were produced. This started with first demonstrating XCZM's ability to model the PSC mechanism in 2D and consequently that methane holes have a noticeable effect on crack propagation speeds. Following on from this, XCZM was benchmarked in 2D against literature experiments and available model data which consequently highlighted that velocity toughening was an integral feature in producing energetically correct fracture speeds. Leading on from this, XCZM was taken into 3D and demonstrated that it produced experimentally observed bifurcation angle from a literature example. This meant that when a 3D graphite brick was modelled that the crack profile was equivalent to an accepted quasi-static profile. As a consequence of this validation, the XCZM approach was able to model PSC and give insight into features that could not be investigated previously including: finer-scale heterogeneous effects on a dynamic crack profile, comparison between Primary and Secondary crack profiles and also, 3D crack interaction with a methane hole, including insight into possible crack arrest. XCZM was shown to improve upon previous 2D models of experiments that showed the plausibility of PSC; this was achieved by eliminating the need for user intervention and also incorporation of irradiation damage effects through User-defined Material properties (UMAT). Finally, while applying XCZM to a full-scale 3D graphite brick including reactor effects, it was shown that PSC is likely to occur under LEFM assumptions and that the Secondary crack initiates before the Primary crack arrests axially meaning that modal analysis would not be able to fully model PSC.
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Fejzo, R. "Dynamic behaviour of concrete structures with cracking". Thesis, Swansea University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.636965.

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The subject of this thesis is the behaviour of concrete structures under dynamic loading conditions and its modelling. In particular, the modelling of material behaviour is treated and a new material model for the description of plain concrete behaviour is proposed. For the modelling of the uncracked concrete behaviour, a strain rate sensitive elasto - viscoplastic material model developed by Bicanic is used. For the modelling of cracked concete behaviour, a distributed - smeared crack representation has been adopted. Crack initiation and propagation are controlled by a crack monitoring algorithm employing a critical strain criterion, allowing multiple cracking and controlled strain softening during the first crack opening cycle, linking the shear transfer across the crack to the magnitude of crack opening and preserving the crack directionality. Implementation of the proposed material model in a finite element computer program DEGDYN is described and a computer program listing is given. An explicit time stepping scheme is used, so the computer memory requirement is small and the program may be run even on small personal computers. Material model and computer program performance are verified using simple examples. Application of the material model in the analysis of the Koyna dam is demonstrated and results of several parameter sensitivity analyses are presented.
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Marazzato, Frédéric. "Discrete element and time-integration methods forelasto-plasticity and dynamic cracking". Thesis, Paris Est, 2020. http://www.theses.fr/2020PESC1001.

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Cette thèse propose des contributions aux méthodes éléments discrets (MED) et à l’intégration temporelle explicite avec pour objectif applicatif les calculs de fissuration et de fragmentation pour des matériaux métalliques soumis à des chargements dynamiques. Les MED, qui sont traditionnellement utilisées pour simuler le comportement de matériaux granulaires, sont ré-interprétées à la lumière des méthodes de discrétisation de gradient afin d’être appliquées à la simulation de matériaux continus. Les maillages utilisables avec la MED proposée ont été étendus des maillages de Voronoi à des maillages polyédriques généraux. Les comportements simulables par la méthode ont été étendus de l’élasto-dynamique à l’élasto-plasticité dynamique par l’ajout d’un degré de liberté tensoriel par cellule. De plus, la méthode est robuste par rap-port à la limite incompressible et ses paramètres ne dépendent que des paramètres matériau. Une méthode d’intégration temporelle explicite conservant une pseudo-énergie, même pour des comportements non-linéaires et des pas de temps variables, a également été développée afin d’éviter une dissipation numérique de l’énergie disponible pour la dissipation plastique et la fissuration. Cette méthode a été couplée avec la MED précédente. Enfin, la propagation de fissures de Griffith à travers les facettes du maillage a été intégrée à la MED pour des comportements élastiques linéaires en deux dimensions d’espace. Le taux de restitution d’énergie est calculé pour chaque mode de fissuration à partir des facteurs d’intensités des contraintes qui sont approchés près de la fissure. Enfin, un critère de maximisation de la densité d’énergie élastique sur les facettes liée à la pointe de fissure permet de simuler l’orientation de la propagation
The present Ph.D. dissertation proposes contributions to discrete element methods (DEM) and explicit time integration schemes with a view towards dynamic cracking for metallic materials under dynamic loading. DEM, which are usually used to simulate granular materials, are understood through the prism of gradient discretization methods in order to simulate continuous materials. The method has been extended from previous Voronoi meshes to support generalpolyhedral meshes. Material behaviours have been extended from elasto-dynamics to dynamic elasto-plasticity through the addition of a tensorial degree of freedom per mesh cell. The method is robust with respect to the incompressible limit and its parameters only depend on material parameters. Moreover, an explicit pseudo-energy conserving time integration method has been developed, even for nonlinear behaviours and variable time steps, so as to avoid thedissipation of energy available for plastic dissipation and cracking. The method has been coupled to the proposed DEM. Finally, Griffith crack propagation through the mesh facets has been adapted to the present DEM for linear elastic behaviours in two space dimensions. The energy release rate is computed for every cracking mode using the stress intensity factors approximated close to the crack. A criterion of maximization of elastic energy density is used tosimulate kinking
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Beskari, Mohamed Ali. "Dynamic analysis of diffusion and convection in porous catalysts". Thesis, University of Salford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244857.

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Illes-Smith, Peter C. "A study of the modelling, dynamic simulation and control of the modern fluid catalytic cracking process". Thesis, University of Leeds, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.330143.

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Añez, Javier. "Modélisation de l'injection de pétrole pour les procédés FCC (Fluid Catalytic Cracking)". Thesis, Normandie, 2018. http://www.theses.fr/2018NORMR132/document.

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Cette thèse est une entreprise commune de VINCI Technologies et du laboratoire CNRS CORIA. De nombreux injecteurs comportent une zone de mélange interne dans laquelle les phases liquides et gazeuses sont toutes deux présentes dans une proportion significative. Par conséquent, cette zone appartient à la catégorie des écoulements diphasiques denses. Pour simuler la dispersion du liquide et caractériser le spray de ces injecteurs, des modèles appropriés sont nécessaires. Les points clés de cette approche sont la dispersion du liquide qui peut être associé au flux liquide turbulent et la quantité de surface liquide-gaz. En particulier, ce manuscrit rapporte, d’une part le développement théorique des modèles de la famille ELSA et, d’autre part, les approximations industrielles correspondantes. Le solveur proposé bascule dynamiquement du spray ICM au spray de sous- maille, à travers le concept ELSA et grâce à l’indicateur basé sur la résolution (IRQ). D’autre part, une fois la zone diluée se forme, l’approche ELSA est couplée à la méthode d’écoulement multiphase, qui vise à déterminer la distribution du spray à l’aide de l’équation WBE. Cette dernière équation est résolue avec une méthode hybride Euler-Lagrange. Le but est de résoudre l’équation WBE avec une approche stochastique Lagrangienne, tout en préservant la compatibilité avec la description Eulerienne de l’écoulement diphasique, basée sur ELSA, pour tirer parti des deux approches. Finalement, ces approches développées ont été utilisées pour des applications industrielles montrant leur robustesse et leur capacité à aider dans le processus de développement de nouveaux injecteurs
This PhD is a joint venture between VINCI Technologies and the CNRS Laboratory CORIA. For its application, VINCI Technologies, developed mainly oil-related equipments and in particular injection/atomization systems. Some of these injectors are characterized by a very big geometrical dimensions (several meters long), that leads to very high Reynolds and Weber number. In addition, many injectors incorporate an internal mixing zone, in which liquid and gas phases are both present in a significant proportion. Consequently, this zone belongs to the dense two-phase flow category. To simulate the liquid dispersion and to characterize the spray formation special from these injectors, appropriate models are required. On its side, the CORIA team, has developed a suitable approach, so-called ELSA, based on the pioneering work of Borghi and Vallet [1, 2]. Key points of this approach are the liquid dispersion that can be associated to the turbulent liquid flux and the amount of liquid-gas surface that can be used to determine eventually the Sauter mean diameter (SMD) of the spray. During this PhD, the applications proposed by V INCI Technologies, have promoted a review of a large part of the multiphase flow approaches to find the more appropriate for each case. This has been the opportunity to clarify the range of application of each approach, and therefore stress the necessity to develop coupled approaches, in order to cover the proposed application in the most suitable way. In particular, this manuscript reports, in one hand, the theoretical development of the ELSA family models, and on the other hand, the corresponding industrial approximations. Since ELSA approaches are originally developed for RANS simulation of the dense zone, it has been extended to LES description. The link of this approach to the DNS¡ ICM approach, has been studied with a special care. The resulting proposed solver, switches dynamically from ICM to subgrid spray, through the ELSA concept, and thanks to resolution based indicator (IRQ). On the opposite side, once the dispersed spray is formed, the ELSA approach is coupled to multiphase flow method, that aims to determine the spray distribution through the WBE equation. This later equation, is solved with an original hybrid Euler-Lagrange method. The purpose is to solve the WBE equation with a Lagrange stochastic approach, and at the same time, preserving the compatibility to the Euler description of two-phase flow, based on ELSA, to benefit from both approaches. This coupled approach has been tested against academic experimental data coming from ECN research initiative, a combined DNS and experimental measurement of dispersed spray on a Diesel jet, and under an air-blast atomizer numerical test case, for which the mean liquid volume fraction has been measured. Eventually, these developed approaches have been applied to industrial application showing there robustness and their capacity to help in the process of design development of new injectors
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Castelo, Branco Veronica Teixeira Franco. "A unified method for the analysis of nonlinear viscoelasticity and fatigue cracking of asphalt mixtures using the dynamic mechanical analyzer". [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-3136.

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Pelissari, Daniel Cícero 1989. "Estudo da influência dos bicos injetores sobre o escoamento gás-sólido e as reações em um riser de FCC via CFD". [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/266017.

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Orientador: Milton Mori
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química
Made available in DSpace on 2018-08-27T17:58:36Z (GMT). No. of bitstreams: 1 Pelissari_DanielCicero_M.pdf: 3433960 bytes, checksum: 82461e75c8ef3d10fb44cd8d35de3eb9 (MD5) Previous issue date: 2015
Resumo: A aplicação de fluidodinâmica computacional (CFD) em estudos de otimização e projeto de novos equipamentos de processos industriais vem aumentando significativamente, uma vez que apresenta custo reduzido e possibilidade de avaliar equipamentos complexos e de extremas condições de operação. Dentre os processos mais estudados via CFD está o processo de craqueamento catalítico fluidizado (FCC), onde as frações pesadas do petróleo de baixo valor são convertidas em produtos de maior valor agregado, sendo uma das aplicações de fluidização gás-sólido mais importante na indústria de petróleo. O presente trabalho avaliou especificamente a zona de injeção do FCC, na qual a matéria-prima, alimentada por bicos injetores, se mistura a sólidos quentes (catalisador) e a vapor de fluidização. A performance desses dispersores de carga para garantir uma boa distribuição das gotículas de gasóleo com o catalisador é a chave para melhorar a eficiência do riser de FCC. Desta forma, o principal objetivo deste trabalho foi avaliar o efeito de diferentes designs, ângulos (30°, 45° e 60°) e configurações dos injetores sobre o escoamento gás-sólido e o desempenho do riser. Para tal, simulou-se um escoamento gás-sólido reativo tridimensional baseado em uma abordagem Eulerian-Eulerian. Nas simulações foram utilizados o modelo cinético de 12-lumps de Wu et al. (2009), modelo de turbulência k-? e modelo de arraste de Gidaspow. Foi observado que o design, o ângulo e a configuração dos bicos injetores exercem uma forte influência sobre a fluidodinâmica e a performance do riser, sendo o ângulo a variável que apresentou maior influência. Pôde-se observar que o design de bico tipo multi-orifícios (Caso 3) foi o que apresentou os melhores resultados, sendo a partir deste avaliados os ângulos, onde notou-se que o aumento do ângulo de 30° para 60° melhorou a mistura entre as fases e o rendimento. A análise dos arranjos foi realizada utilizando o design de bico do Caso 3 e o ângulo de 45°, e observou-se que o arranjo com bicos intercalados (Arranjo 2) apresentou uma mistura mais homogênea entre as fases e, consequentemente, uma melhor conversão e rendimento de produtos desejados. Em geral, os resultados obtidos no presente trabalho salientam a importância da utilização de geometrias mais detalhadas para os bicos, uma vez que influenciam a mistura entre as fases, a qual afeta o desempenho do riser
Abstract: The Computational Fluid Dynamic (CFD) application in industrial process optimization and new equipments design studies has increased significantly, once it presents low cost and the possibility of evaluating complex and extreme operating conditions equipments . Among the most widely studied processes via CFD is the fluidized catalytic cracking process (FCC), where the oil heavy fractions of low-value are converted into higher value-added products and which is one of the most important gas-solid fluidization applications in the oil industry . The present study specifically evaluated the FCC injection zone, in which the feedstock fed by nozzles, is mixed with hot solids (catalyst) and fluidization steam. The nozzles performance to guarantee a good gas oil droplets distribution with the catalyst is the key to improve the efficiency of FCC riser. Thus, the study main objective was to evaluate the different nozzles designs, angles (30 °, 45 ° and 60 °) and arrangements effect on the gas-solid flow and the riser performance. For this purpose, it was simulated a three-dimensional reactive gas-solid flow based on an Eulerian-Eulerian approach. In the simulations it was used the 12 lumps kinetic model by Wu et al. (2009), turbulence model k- ? and drag model Gidaspow. It was observed that the nozzle design, angle and configuration have a strong influence on fluid dynamics and on the riser performance, and the angle was the variable with the greatest influence. It can be observed that the nozzle design of multi-orifice type (Case 3) showed the best results, and that¿s why it was used to evaluate the angle, in which was noted that the angle increase of 30 ° to 60 ° improved phases mixing and the yield. The arrangement analysis was performed using Case 3 nozzle design and the design angle of 45 °, and it was observed that the arrangement with intercalated nozzles (Arrangement 2) showed a more homogeneous phases mixture and therefore a better conversion and desired product yield. In general, the results obtained in this work highlighted the importance of using more detailed geometries for the nozzles, since they influence the mixing of the phases, which affects the riser performance
Mestrado
Engenharia Química
Mestre em Engenharia Química
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Wade, James. "Contact damage of ceramics and ceramic nanocomposites". Thesis, Loughborough University, 2017. https://dspace.lboro.ac.uk/2134/24932.

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Herein, we study the contact damage performance of two armour ceramics, alumina and silicon carbide, with varying microstructures and one particle-reinforced ceramic nanocomposite, alumina/silicon carbide, in an attempt to understand the microstructural mechanisms that affect plasticity and cracking under quasi-static and dynamic conditions. Quasi-static contact damage was imitated using Vickers indentation over a varying load regime. Numerical analysis of the indentation size effect, performed using the proportional specimen resistance model, allowed the contributions of plastic deformation and cracking to be separated into two individual values. In all three samples, higher levels of surface energy were found to correlate with increased amounts of cracking per unit area of indentation impression. Analytical modelling of crack initiation during Vickers indentation together with quantitative measurements of surface flaw populations revealed that such an increase in cracking damage was the result of higher densities of larger flaws. The hardness of the monolithic ceramics was found vary based on grain size and porosity levels, a smaller average grain size and lower porosity levels resulting in higher hardness values. In the nanocomposite materials, hardening was found to occur with further additions of silicon carbide nanoparticles. Such an effect has been attributed to the increased dislocation densities, as measured using Cr3+/Al2O3 fluorescence spectroscopy, and the impedance of dislocation movement within the lattice due to the presence of silicon carbide nanoparticles. In order to simulate dynamic contact damage, a low velocity, scaled-down drop-weight test was designed and developed. The dynamic contact damage resistance was determined based on the depth of penetration of a blunt indenter. In the monolithic ceramics, the indenter penetration was found to be shallower in materials of higher hardness. However, the nanocomposite materials displayed an opposing trend, the indenter penetration becoming deeper in the samples of higher hardness. The macro-scale fracture patterns produced during drop-weight impacts were seen to vary based on flaw populations and indenter penetration. In certain microstructures, extensive micro-cracking was also observed.
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Eksi, Murat. "Optimization Of Mechanical And Microstructural Properties Of Weld Joints Between Aluminium-magnesium And Aluminium-magnesium-silicon Alloys With Different Thicknesses". Master's thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615649/index.pdf.

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For the last decades usage of aluminium alloys have been increasing tremendously. They have been used in aerospace industry widely and now aluminium alloys are becoming more and more popular in automotive and defense industries. Consequently
successful welding of aluminium alloys gains importance. In this study a research is carried out on eldability of plates having different thicknesses of composition 5754 aluminium and 6063 aluminium in T-fillet geometry using Gas-metal Arc Welding technique. It was aimed to have a successful joint without using pre-weld and post-weld heat treatments. During tests welding current and voltage were the varying parameters as welding speed was held constant. Macro-examinations were performed to see the penetration of the weld metal. It was seen that the type of filler wire greatly effects weld penetration. Hardness tests, tensile tests were done to compare the mechanical properties of the welded joints with different filler wires. Despite having better penetration in 4043 filler wire used weld joints, 5356 filler wire used weld joints had higher tensile strength and ductility. In the second part of the study, a dynamic loading machine was designed and manufactured to see the behavior of the fillet welds under dynamic loading. The amount of stress and strain given to the specimen on this machine was adjustable but can&rsquo
t be measured. The tests that were made with this machine aimed only to compare the number of cycles of specimens before fracture. For dynamic loading tests two groups of specimens were prepared with filler wire 4043
each group having been welded with different heat inputs. It was aimed to see the effect of welding heat input on service lifes but no significant difference between cycle numbers of specimen groups having been welded with different heat inputs was observed. Microstructure examinations of these specimens revealed that coarsening the grains, grain boundaries, particles in PMZ and HAZ regions between Al 6063 base metal and weld zone made these areas more susceptible and favorable for crack propogation than Al 6063 base metal.
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Livros sobre o assunto "Dynamic cracking"

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Dumanoğlu, A. Aydın. Beton ağırlık barajlarının dinamik davranışına çatlak etkisi =: The effects of cracks on the dynamic response of concrete gravity dams. Maslak, İstanbul: Türkiye Deprem Vakfı, 1999.

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J, Olson R., Battelle Memorial Institute e U.S. Nuclear Regulatory Commission. Office of Nuclear Regulatory Research. Division of Engineering., eds. Validation of analysis methods for assessing flawed piping subjected to dynamic loading. Washington, DC: U.S. Nuclear Regulatory Commission, 1994.

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3

United States. National Aeronautics and Space Administration. Scientific and Technical Information Division., ed. Fracture toughness and crack growth of Zerodur. [Washington, DC]: National Aeronautics and Space Administration, Office of Management, Scientific and Technical Information Division, 1990.

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4

E, Vallejo Luis, Liang Robert Y, American Society of Civil Engineers. Geotechnical Engineering Division. e ASCE National Convention (1994 : Atlanta, Ga.), eds. Fracture mechanics applied to geotechnical engineering: Proceedings of sessions sponsored by the Geotechnical Engineering Division of the American Society of Civil Engineers in conjunction with the ASCE National Convention in Atlanta, Georgia, October 9-13, 1994. New York, N.Y: American Society of Civil Engineers, 1994.

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Johannes Petrus Bernardus Nicolaas Derks. Cold fluid driven crack propagation: Thermo-mechanical behaviour of rock caverns. Delft, The Netherlands: Delft University Press, 1997.

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6

G, Advani Suresh, ed. Flow and rheology in polymer composites manufacturing. Amsterdam: Elsevier, 1994.

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R, Talreja, ed. Damage mechanics of composite materials. Amsterdam [The Netherlands]: Elsevier, 1994.

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8

Gujarathi, Manoj Sharad. Pavement roughness characteristics affecting the dynamic loads of heavy vehicles. 1994.

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9

Fatigue and crack growth: Environmental effects, modeling studies, and design considerations : presented at the 1995 Joint ASME/JSME Pressure Vessels and Piping Conference, Honolulu, Hawaii, July 23-27, 1995. New York: American Society of Mechanical Engineers, 1995.

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10

(Editor), S. Yukawa, D. P. Jones (Editor) e H. S. Mehta (Editor), eds. Fatigue and Crack Growth: Environmental Effects, Modeling Studies, and Design Considerations: Presented at the 1995 Joint Asme/Jsme Pressure Ves (Pvp). American Society of Mechanical Engineers, 1995.

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Capítulos de livros sobre o assunto "Dynamic cracking"

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Saouma, Victor E., e M. Amin Hariri-Ardebili. "Transient Dynamic Analysis". In Aging, Shaking, and Cracking of Infrastructures, 123–39. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-57434-5_6.

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Chen, Yueyao, Qianjun Liu, Tianyu Du, Yuan Chen e Shouling Ji. "Symmetric Frame Cracking: A Powerful Dynamic Textual CAPTCHAs Cracking Policy". In Information Security and Cryptology, 157–72. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-42921-8_9.

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Krupp, Ulrich. "Dynamic Embrittlement - Diffusion-Induced Intergranular Cracking". In Defect and Diffusion Forum, 192–98. Stafa: Trans Tech Publications Ltd., 2006. http://dx.doi.org/10.4028/3-908451-36-1.192.

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Kirkbir, F., e B. Kisakurek. "Dynamic Analysis of an Ethane Cracking Reactor". In Chemical Reactor Design and Technology, 779–94. Dordrecht: Springer Netherlands, 1986. http://dx.doi.org/10.1007/978-94-009-4400-8_22.

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Komai, K., e K. Minoshima. "Dynamic and Cyclic Stress Corrosion Cracking Resistance of Metals". In Advanced Materials for Severe Service Applications, 373–88. Dordrecht: Springer Netherlands, 1987. http://dx.doi.org/10.1007/978-94-009-3445-0_24.

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Miranda, William Ferreira, Suzana Moreira Avila e Graciela Nora Doz. "Cracking Influence on Dynamic Parameters of Reinforced Concrete Floors". In Conference Proceedings of the Society for Experimental Mechanics Series, 211–16. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-74421-6_28.

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Nagy, Peter B., e Gabor Blaho. "Identification of Distributed Fatigue Cracking by Dynamic Crack-Closure". In Review of Progress in Quantitative Nondestructive Evaluation, 1979–86. Boston, MA: Springer US, 1995. http://dx.doi.org/10.1007/978-1-4615-1987-4_253.

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Ramos, K. J., B. J. Jensen, J. D. Yeager, C. A. Bolme, A. J. Iverson, C. A. Carlson e K. Fezzaa. "Investigation of Dynamic Material Cracking with In Situ Synchrotron-Based Measurements". In Dynamic Behavior of Materials, Volume 1, 413–20. Cham: Springer International Publishing, 2013. http://dx.doi.org/10.1007/978-3-319-00771-7_50.

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Chiang, Po-Ju, Runbo Jiang, Ross Cunningham, Niranjan Parab, Cang Zhao, Kamel Fezzaa, Tao Sun e Anthony D. Rollett. "In Situ Characterization of Hot Cracking Using Dynamic X-Ray Radiography". In Advanced Real Time Imaging II, 77–85. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-06143-2_8.

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Hamzah, M. O., M. R. M. Hasan, M. F. C. Ven e J. L. M. Voskuilen. "Development of Dynamic Asphalt Stripping Machine for Better Prediction of Moisture Damage on Porous Asphalt in the Field". In 7th RILEM International Conference on Cracking in Pavements, 71–81. Dordrecht: Springer Netherlands, 2012. http://dx.doi.org/10.1007/978-94-007-4566-7_8.

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Trabalhos de conferências sobre o assunto "Dynamic cracking"

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Rho, Jong Hyun, Michael Baldea, Elizabeth E. Endler, Monica A. Herediac, Vesna Bojovic e Pejman Pajand. "The Impact of Electri?ed Process Heating on Process Design, Control and Operations". In Foundations of Computer-Aided Process Design, 570–77. Hamilton, Canada: PSE Press, 2024. http://dx.doi.org/10.69997/sct.134037.

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We study the impact of switching from combustion heating to electric heating in processes comprising high temperature reaction/separation sequences, where the heat supporting the reaction(s) is substantially provided by combusting a reaction byproduct (fuel gas). A canonical process structure is de?ned. It is shown that the conventional combustion- based process presents signi?cant interactions. An asymptotic analysis is utilized to investigate and compare the dynamic responses of the conventional and electric process configurations. It is demonstrated that the dynamic behavior of the two processes exhibits two timescales, with the faster corresponding to the evolution of the temperatures of the units with high heat duty, and the slow time scale capturing the variables involved in the material balance. A simpli?ed ethylene cracking process example is used to demonstrate these findings.
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Mosnier, Martial, Fre´de´ric M. B. Mercier, Je´roˆme Renard e Patrice Bailly. "An Experimental Investigation on Metallic Plates Dynamic Cracking". In ASME 2005 Pressure Vessels and Piping Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/pvp2005-71385.

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Metallic pressure vessels are of common use in the industrial field. They can contain either gases or liquefied gases. If a sudden pressure rise happens inside one of these vessels for any reason (human mistake, uncontrolled chemical reaction, BLEVE, rise in mass, explosion...), it can result in the bursting of the vessel. Though a pressure rise is relatively frequent, the response of the vessel to that sort of load cannot be easily forecasted, since the phenomenon is dynamic. Moreover, except from statistical studies, few experimental data are available on the topic. Therefore, an experimental study can help to understand the behavior of a pressurized enclosure in relation to such a solicitation. This paper analyzes the results of a set of experiments, that have been achieved in order to identify the mechanisms of a vessel rupture. The experimental device consists in a two-parts shock tube between which the sample, viz. a metallic plate, is set. This shock tube is fitted out with pressure gages. The plates are equipped out with strain and crack propagation gages. These sensors, in addition to a high velocity camera make possible the study of dynamic crack formation and fracture propagation on samples submitted to an explosion. Various classes of material with different ductilities have been tested. Moreover, the plate thickness influence has also been investigated. Flaws have been machined as external axial surface notches to produce and control cracking. Various solicitations have also been browsed: the loads were different kinds of explosions produced by the deflagration or the detonation of a stoichiometric hydrogen-oxygen mixture. Preliminary tests have shown a good reproducibility of the experiments. The loading amplitude (the pressure curves) and the shape of the plates after the operation, and especially the crack opening, are almost identical. These experiments have allowed to have a first overview of the role of the different input parameters on the plate behavior under load, and the way cracking occurs. The input parameters that have been monitored are the material ductility, the thickness of the samples and the kind of loading that is applied to them (i.e. different velocities deflagrations, detonations and so on). Output parameters are the strain rate of the plates and their cracking. Cracking is characterized by the size and the shape of the crack, its fracture facies and propagation velocity. In this paper, fracture behavior has been discussed with regard to the above mentioned parameters.
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Yazhen Sun, Minjiang Zhang e Fuxiao Zhao. "Reflective cracking dynamic response of asphalt concrete under vehicle loading". In 2011 Second International Conference on Mechanic Automation and Control Engineering (MACE). IEEE, 2011. http://dx.doi.org/10.1109/mace.2011.5987471.

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Mythily, M., D. Manamalli e P. Manikandan. "Dynamic Modeling, Simulation and Multivariable Control Strategy Applied to Catalytic Cracking Unit". In 2011 International Conference on Process Automation, Control and Computing (PACC). IEEE, 2011. http://dx.doi.org/10.1109/pacc.2011.5978937.

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Majzoub, R., e Mohammad M. Chaudhri. "Visualization of low-velocity dynamic indentation cracking of an epoxy and polymethylmethacrylate". In 25th international Congress on High-Speed photography and Photonics, editado por Claude Cavailler, Graham P. Haddleton e Manfred Hugenschmidt. SPIE, 2003. http://dx.doi.org/10.1117/12.516948.

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Miki, Yoshihiko, e Hirobumi Watanabe. "Evaluation of dynamic bonding stress and interlayer cracking using a combo sensor". In 2012 IEEE International Conference on Microelectronic Test Structures (ICMTS). IEEE, 2012. http://dx.doi.org/10.1109/icmts.2012.6190647.

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Mani, Arun K., e Oluwasola Mary Adedayo. "Dynamic Calculation of Password Salts for Improved Resilience towards Password Cracking Algorithms". In 2024 12th International Symposium on Digital Forensics and Security (ISDFS). IEEE, 2024. http://dx.doi.org/10.1109/isdfs60797.2024.10527313.

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Wang, Jingru, Yuetian Liu, Yuting He, Xinju Liu, Ziyu Lin, Bowei Zhang e Rukuan Chai. "Stress Corrosion Cracking in Carbonates Initiated by Carbonic Acid, A Reactive Molecular Dynamic Simulation". In 58th U.S. Rock Mechanics/Geomechanics Symposium. ARMA, 2024. http://dx.doi.org/10.56952/arma-2024-0078.

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ABSTRACT: As the greenhouse effect gradually intensifies, addressing CO2 as the primary greenhouse gas has become a pressing concern. Currently, the predominant carbon sequestration technique involves storing CO2 in reservoirs or saline aquifers. However, CO2 readily dissolves in water, forming carbonic acid, which can compromise geological formations and lead to stress corrosion cracking. Stress corrosion cracking (SCC), a chemical activation mechanism, involves fluid adsorption on crack surfaces and fluid-assisted crack propagation. While there is extensive research on the stress corrosion cracking of CO2 in quartz crystals, investigations on stress corrosion cracking in gas-water-carbonate rock systems remain limited. Moreover, the carbonic acid formed when CO2 dissolves in water can engage in complex chemical reactions with carbonate rocks, exacerbating the corrosion and cracking of carbonate rocks. This study focuses on carbonate reservoirs, representing them using calcite crystals. Molecular dynamics simulation is employed to investigate stress corrosion cracking in pre-cracked calcite crystals under fluid interaction. By comparing the cracking behavior of calcite crystals in different environments, the intrinsic mechanisms of crack propagation are analyzed. This study indicates that carbonate fluids have a strong impact on the subcritical expansion of cracks. During the stress corrosion cracking process, Ca-O bonds are the first to break. H atoms from the external environment readily form H-O bonds and C-H bonds on the surface of calcite, with H-O bonds binding to Ca atoms, accelerating the fracture of Ca-O bonds. In a carbonate environment, H atoms infiltrate the interior of calcite more rapidly, binding with C and O atoms, creating crystal vacancies, and intensifying the extent of stress corrosion cracking. This study aims to explore the damage to carbonate rock reservoirs during the CO2 storage process and analyze the gas-water-rock interactions in enhanced oil recovery with CO2 injection or during CO2 fracturing processes. These findings contribute to describing the details of rock fracturing and provide insights for the development of effective oil and gas extraction and carbon sequestration technologies.
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Zhao, Yanjing, Fujian Ni e Lan Zhou. "Viscoelastic Response of Reflective Cracking under Dynamic Vehicle Loading in Asphalt Concrete Pavements". In 11th International Conference of Chinese Transportation Professionals (ICCTP). Reston, VA: American Society of Civil Engineers, 2011. http://dx.doi.org/10.1061/41186(421)326.

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Goudarzi, N., H. Vafakhah e Y. Korany. "Investigation of the Post-Cracking Dynamic Behavior of Masonry Structures Retrofitted with CFRP". In Structures Congress 2013. Reston, VA: American Society of Civil Engineers, 2013. http://dx.doi.org/10.1061/9780784412848.105.

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Relatórios de organizações sobre o assunto "Dynamic cracking"

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Underwood, John H. Standards for Ordnance Materials; Dynamic Fracture and Environmental Cracking Applications. Fort Belvoir, VA: Defense Technical Information Center, abril de 1994. http://dx.doi.org/10.21236/ada281217.

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DeSantis, John, e Jeffery Roesler. Longitudinal Cracking Investigation on I-72 Experimental Unbonded Concrete Overlay. Illinois Center for Transportation, fevereiro de 2022. http://dx.doi.org/10.36501/0197-9191/22-002.

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A research study investigated longitudinal cracking developing along an experimental unbonded concrete overlay (UBOL) on I-72 near Riverton, Illinois. The project evaluated existing literature on UBOL (design, construction, and performance), UBOL case studies, and mechanistic-empirical design procedures for defining the mechanisms that are contributing to the observed distresses. Detailed distress surveys and coring were conducted to assess the extent of the longitudinal cracking and faulting along the longitudinal lane-shoulder joint. Coring over the transverse contraction joints in the driving lane showed stripping and erosion of the dense-graded hot-mix asphalt (HMA) interlayer was the primary mechanism initiating the longitudinal cracks. Cores from the lane-shoulder joint confirmed stripping and erosion was also occurring there and leading to the elevation difference between the driving lane and shoulder. Field sections by surrounding state departments of transportation (DOTs), such as Iowa, Michigan, Minnesota, Missouri, and Pennsylvania, with similar UBOL design features to the I-72 section were examined. Site visits were performed in Illinois, Michigan, Minnesota, and Pennsylvania, while other sections were reviewed via state DOT contacts as well as Google Earth and Maps. Evidence from other DOTs suggested that HMA interlayers, whether dense graded or drainable, could experience stripping, erosion, and instability under certain conditions. An existing performance test for interlayers, i.e., Hamburg wheel-tracking device, and current models reviewed were not able to predict the distresses on I-72 eastbound. Adapting a dynamic cylinder test is a next step to screen HMA interlayers (or other stabilized layers) for stripping and erosion potential. To slow down the cracking and faulting on I-72 eastbound, sealing of the longitudinal lane-shoulder joint and driving lane transverse joints is suggested. To maximize UBOL service life, an HMA overlay will minimize water infiltration into the interlayer system and significantly slow down the HMA stripping and erosion mechanism that has led to longitudinal cracking and lane-shoulder faulting.
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Subramanian, K. H. Test Plan to Update SRS High Level Waste Tank Material Properties Database by Determining Synergistic Effects of Dynamic Strain Aging and Stress Corrosion Cracking. Office of Scientific and Technical Information (OSTI), março de 2002. http://dx.doi.org/10.2172/799694.

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Rahbar-Rastegar, Reyhaneh, Gerald Huber, Miguel A. Montoya, Christopher Campbell e John E. Haddock. Demonstration Project for Asphalt Performance Engineered Mixture Design Testing. Purdue University, 2022. http://dx.doi.org/10.5703/1288284317382.

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The asphalt industry is moving towards performance-based methods for asphalt mixture design. The Federal HighwayAdministration (FHWA) is supportive of state departments of transportations (DOT) adopting index and predictive performance tests, especially those making use of the Asphalt Mixture Performance Tester (AMPT). The FHWA is therefore encouraging state DOTs to gain experience with the requirements of the procedures and analysis tools for Balanced Mixture Design (BMD). The main objective of this study is to evaluate fatigue cracking on three INDOT mainline pavement projects that have asphalt mixtures designed by the Superpave 5 mixture design, and to better understand the fundamental engineering testing capabilities of the AMPT. A total of four Superpave 5 asphalt mixtures were collected and tested from the three projects. The viscoelastic characteristics and fatigue behavior of plant-mixed, laboratory compacted (PMLC), laboratory-mixed, laboratory compacted (LMLC), and plant-mixed, field compacted (PMFC) specimens were assessed according to the AASHTO TP-132 and AASHTO TP-133 test methods. Two AMPT machines (IPC Controls and PaveTest) were used to conduct the dynamic modulus tests, while all fatigue tests were performed using a PaveTest AMPT. The raw data were analyzed using the FlexMAT software. The dynamic modulus and cyclic fatigue test results indicate that AMPT testing can be used to effectively evaluate INDOT asphalt mixtures during the mixture design and production phases. However, to do so, detailed planning and effective training are needed to help ensure the successful completion of AMPT testing.
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Ko, Yu-Fu, e Jessica Gonzalez. Fiber-Based Seismic Damage and Collapse Assessment of Reinforced Concrete Single-Column Pier-Supported Bridges Using Damage Indices. Mineta Transportation Institute, agosto de 2023. http://dx.doi.org/10.31979/mti.2023.2241.

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Near-fault earthquakes can have major effects on transportation systems due to the structural damage they impose on bridges. Therefore, it is imperative to assess the seismic damage of bridges appropriately, and this research focuses on reinforced concrete (RC) bridges. This research advances the seismic performance assessment of RC single-column pier-supported bridges with flexural failure under near-fault ground motion by use of ductility coefficients and damage indices. The methodology included modeling fiber-based nonlinear beam-column elements to simulate the damage development process of RC bridge piers under earthquake loadings, considering the global buckling of longitudinal steel bars, examining the cracking and spalling of cover concrete, and analyzing the effects of bond-slip. The tensile strain represented the damage of the longitudinal bars while the compression strain represented the cover concrete damage. Two innovative nonlinear fiber-based finite element models (FEMs) were developed: Model 1 (bond-slip excluded) and Model 2 (bond-slip included). Nonlinear static cyclic pushover analyses and nonlinear response history analyses were conducted. The simulation results were compared with available pseudo-dynamic test results. Model 1 provided a more ideal prognosis on the seismic performance of RC single-column pier-supported bridges under near-fault ground motion. The proposed damage indices can indicate the damage state at any stage and the gradual accumulation of damage in RC bridge piers, which are more convincing than most other indices in the literature. The proposed fiber-based nonlinear FEMs, together with the use of ductility coefficients and proposed damage indices, can also assist engineers and researchers in simulating the seismic behavior and assessing the damage state of RC bridge columns in a computationally effective manner which can empower engineers to identify and prioritize RC bridges for seismic retrofit and maintenance.
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Bastawros, Ashraf. DTPH56-16H-CAP01 Mechanochemistry-Based Detection of Early Stage Corrosion Degradation of Pipeline Steels. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), maio de 2020. http://dx.doi.org/10.55274/r0011990.

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The aim of the work is to provide measurable precursor signals associated with the initiation stage of near-surface damage and cracking, as depicted in Fig. 1.1. We have identified many salient features during the early stage of the SCC process (Stages 1, 2 on Fig. 1.1), including residual stress build-up, near-surface (within few microns) defect percolation, and changes of dislocation dynamics and measurable changes of the surface osmic resistance. We developed a model-based prediction of the onset and progression of SCC subsurface damage and assessed the electrochemical impedance spectroscopy (EIS) to measure the extent of surface damage. Such a framework would enable the development of appropriate field-deployable NDE technology with the needed spatial and temporal resolutions.
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Wei, Fulu, Ce Wang, Xiangxi Tian, Shuo Li e Jie Shan. Investigation of Durability and Performance of High Friction Surface Treatment. Purdue University, 2021. http://dx.doi.org/10.5703/1288284317281.

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The Indiana Department of Transportation (INDOT) completed a total of 25 high friction surface treatment (HFST) projects across the state in 2018. This research study attempted to investigate the durability and performance of HFST in terms of its HFST-pavement system integrity and surface friction performance. Laboratory tests were conducted to determine the physical and mechanical properties of epoxy-bauxite mortar. Field inspections were carried out to identify site conditions and common early HFST distresses. Cyclic loading test and finite element method (FEM) analysis were performed to evaluate the bonding strength between HFST and existing pavement, in particular chip seal with different pretreatments such as vacuum sweeping, shotblasting, and scarification milling. Both surface friction and texture tests were undertaken periodically (generally once every 6 months) to evaluate the surface friction performance of HFST. Crash records over a 5-year period, i.e., 3 years before installation and 2 years after installation, were examined to determine the safety performance of HFST, crash modification factor (CMF) in particular. It was found that HFST epoxy-bauxite mortar has a coefficient of thermal expansion (CTE) significantly higher than those of hot mix asphalt (HMA) mixtures and Portland cement concrete (PCC), and good cracking resistance. The most common early HFST distresses in Indiana are reflective cracking, surface wrinkling, aggregate loss, and delamination. Vacuum sweeping is the optimal method for pretreating existing pavements, chip seal in particular. Chip seal in good condition is structurally capable of providing a sound base for HFST. On two-lane highway curves, HFST is capable of reducing the total vehicle crash by 30%, injury crash by 50%, and wet weather crash by 44%, and providing a CMF of 0.584 in Indiana. Great variability may arise in the results of friction tests on horizontal curves by the use of locked wheel skid tester (LWST) due both to the nature of vehicle dynamics and to the operation of test vehicle. Texture testing, however, is capable of providing continuous texture measurements that can be used to calculate a texture height parameter, i.e., mean profile depth (MPD), not only for evaluating friction performance but also implementing quality control (QC) and quality assurance (QA) plans for HFST.
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