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Letteratura scientifica selezionata sul tema "Tensile zone"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 20 febbraio 2023

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Articoli di riviste sul tema "Tensile zone"

Zhou, Yi, Meng Cui, Dequan Zhou, Xiaojia Wang e Xiao Fu. "Meso-Experimental Study on Tensile Characteristics of Clay". Advances in Civil Engineering 2021 (29 marzo 2021): 1–16. http://dx.doi.org/10.1155/2021/8875903.

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This paper presents an experimental study on the meso-structure change of clay using an innovative testing system. It aims to evaluate the tensile characteristics of clay. The testing system designed in this paper includes a tensile loading device, an image acquisition device, and an image processing program, which can collect and process the meso-structural images of the soil sample and predict the location of tensile fracture zone with a small preloading. The tests were conducted with three different observation zones, including the tensile fracture zone (Zone 1), the adjacent area of tensile fracture zone (Zone 2), and the areas away from the tensile fracture zone (Zone 3). The results show that the development of cracks is continuous but not linear until tensile failure in Zone 1, and the cracks emerge but stop developing in Zone 2 with the penetration of the cracks in Zone 1, while there is only an overall deviation without any cracks in Zone 3. The variety of mesostructural quantitative parameters in Zone 1 can be divided into three stages: stable stage, rapid change stage, and failure stage. The changes of parameters in Zone 2 show a similar law with those in Zone 1, but the variation is smaller due to the cessation of cracks. The parameters in Zone 3 essentially remain unchanged throughout the whole procedure. According to the test results, the whole stretching process of clay can be divided into the sprouting, the development, and the penetration of cracks.

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Zheng, Yi, Yao Hui Liu, Yu Lai Song, Jia’an Liu, Ling Nan Kong e Yan Liang. "Effect of Welding Heat Input on Microstructure and Softening Behavior of 5CrMoV Steel". Key Engineering Materials 735 (maggio 2017): 42–48. http://dx.doi.org/10.4028/www.scientific.net/kem.735.42.

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Three different heat input combinations for the medium carbon alloy steels 5CrMoV are compared in terms of the heat affected zone of microstructures, hardness, and tensile properties. The microstructures in the heat affected zone are predominately ferrite and bainite, with grain size variation in different sub-zones and different heat input. Analyses of the micro-hardness profiles indicated that softening phenomenon occurs in the entire heat affected zone, and high heat input resulted in the greatest decrease in hardness. The results of the tensile tests reveal tensile properties of the heat affected zone deteriorate with the increase of heat input, and the region at temperatures near Ac1 is the weakest part of heat affected zone.

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Darwis, Mardis, Rudy Djamaluddin, Rita Irmawaty e Astiah Amir. "Analisis Pola Kegagalan Balok Sistem Rangka dengan Perkuatan di Daerah Tumpuan". Jurnal Penelitian Enjiniring 24, n. 1 (26 ottobre 2020): 17–23. http://dx.doi.org/10.25042/jpe.052020.03.

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The previous research of using truss system reinforcement in the beam without concrete (BTR) in the tension zone causes a decrease in flexural capacity due to the failure in the area near the support. Therefore, it is necessary to add tensile reinforcement in the support zone. This study aims to analyze the ultimate capacity of the truss system concrete beam strengthened with tensile reinforcement and to analyze the effect of tensile reinforcement in support zone due to crack pattern. This study was conducted experimentally in the laboratory. The dimension of truss reinforced concrete specimens are 15 cm x 20 cm x 330 cm that added tensile reinforcement with three types of length, they are BTRP 40D, BTRP 50D, and BTRP 60D, where D (13 mm) is diameter of tensile reinforcement. The flexural test is carried out by monotonic static loading. The results showed that tensile reinforcement in BTRP 40D was not able to carry the ultimate capacity due to premature failure in the support zone. while BTRP 50D and BTRP 60D specimens can enhance the ultimate capacity without facing premature failure in the support zone. The tensile reinforcement of 60D has the highest ultimate capacity because it can carry the biggest loads and minimum crack pattern.

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EL-NEMER, SAMIR. "INHOMOGENEOUS DEFORMATION ZONE IN TENSILE SPECIMEN". International Conference on Applied Mechanics and Mechanical Engineering 1, n. 1 (1 maggio 1986): 35–42. http://dx.doi.org/10.21608/amme.1986.51834.

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Baskutis, Saulius, Jolanta Baskutiene e Edvinas Bernotaitis. "Experimental Study of Welded Joints of Aluminium Alloy AW6082". Solid State Phenomena 260 (luglio 2017): 212–18. http://dx.doi.org/10.4028/www.scientific.net/ssp.260.212.

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This paper considers mechanical properties of the welded joints of aluminium alloy AW6082 under varying metal inert gas welding conditions, determined by tensile and microhardness tests. The test joints were produced at different welding current and welding speed. Cross sections of the welding zones have been analysed. The influence of heat input on the tensile strength properties and hardness of the base metal, heat affected and fusion zones were studied. The behaviour of double-V butt weld joints was investigated by tensile tests. Static tensile test and metallographic examination results showed minimum strength in the heat affected zone (HAZ). It was found that the lowest hardness values were obtained in the fusion zone and near the fusion line where rupture occurred.

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Chen, Qing Feng, Zhong Hui Chen, Ning Ma, Wei Zhang e Hui Li. "The Zonal Disintegration Law within Coal in Front of Working Face in Deep Coal Mine". Applied Mechanics and Materials 353-356 (agosto 2013): 1082–89. http://dx.doi.org/10.4028/www.scientific.net/amm.353-356.1082.

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The mining coal in the front of long wall face consists of elastic zone, plastic zone and fracture zone. Based on the research of zonaldisintegration of surrounding rock mass in deep tunnel, the zonal disintegration phenomenon of deep coal mine was analyzed by using the theoretical analysis method. On the basis of the Griffith theory, the internal and external boundary formulas of fracture zone and the mechanical criteria of zonal disintegration were obtained. The research shows that the essence of zonal disintegration is the tensile failure and brittle tension crack failure under the abutment pressure, the main influence factors of the width variation of fracture zone are original rock stress and un-axial tensile strength of coal.

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Snider, G. R., J. Lomakin, M. Singh, S. H. Gehrke e M. S. Detamore. "Regional Dynamic Tensile Properties of the TMJ Disc". Journal of Dental Research 87, n. 11 (novembre 2008): 1053–57. http://dx.doi.org/10.1177/154405910808701112.

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Although the TMJ disc has been well-characterized under tension and compression, dynamic viscoelastic regional and directional variations have heretofore not been investigated. We hypothesized that the intermediate zone under mediolateral tension would exhibit lower dynamic moduli compared with the other regions of the disc under either mediolateral or anteroposterior tension. Specimens were prepared from porcine discs (3 regions/direction), and dynamic tensile sweeps were performed at 1% strain over a frequency range of 0.1 to 100 rad/sec. Generally, the intermediate zone possessed the lowest storage and loss moduli, and the highest loss tangent. This study further accentuates the known distinct character of the intermediate zone by showing for the first time that these differences also extend to dynamic behavior, perhaps implicating the TMJ disc as a structure primarily exposed to predominantly anteroposterior tension via anterior and posterior attachments, with a need for great distension mediolaterally across the intermediate zone.

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NESSLER, J. P., P. C. AMADIO, L. J. BERGLUND e K. N. AN. "Healing of Canine Tendon in Zones Subjected to Different Mechanical Forces". Journal of Hand Surgery 17, n. 5 (ottobre 1992): 561–68. http://dx.doi.org/10.1016/s0266-7681(05)80242-6.

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The effect of external force environment on the healing of a partial thickness injury to canine flexor tendon was studied. A 50% laceration was made in either the fibrocartilaginous (compressive) zone or in the tendinous (tensile) zone of canine flexor digitorum profundus tendons. After three or six weeks, the tendons were harvested. An optical method for determining zone-specific material properties showed that, in response to injury, the structural stiffness decreased in the tensile zone of the tendon but increased in the compressive zone. The mechanical properties and failure mechanism of canine tendon and their changes in response to injury vary according to tendon zone, and differences in the healing process in mechanically specialised zones of the flexor tendon are discussed.

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Parasuraman, Prabhuraj, Tushar Sonar e Selvaraj Rajakumar. "Microstructure, tensile properties and fracture toughness of friction stir welded AA7075-T651 aluminium alloy joints". Materials Testing 64, n. 12 (29 novembre 2022): 1843–50. http://dx.doi.org/10.1515/mt-2022-0212.

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Abstract The main objective of this investigation is to study the microstructure, tensile properties and fracture toughness of friction stir welded (FSW) butt joints of 10 mm thick AA7075-T651 plates. The microstructural features of stir zone (SZ), thermos-mechanically affected zone (TMAZ), heat affected zone (HAZ) were analyzed using optical microscopy technique. The tensile properties were evaluated using smooth and notch tensile specimens and compared to base metal properties. The microhardness survey was done across the weld cross section and correlated to the failure of tensile specimens. Compact tension (CT) specimens were used to evaluate the fracture toughness of welded joints. The fractured tensile and CT specimens were analyzed using scanning electron microscopy (SEM). Results showed that the FSW AA7075-T651 specimens welded using axial load of 12 kN, tool rotation speed of 750 rpm and welding speed of 30 mm/min exhibited 412 MPa tensile strength and 9% elongation. It showed 88 and 89% of base metal strength elongation. The joints showed fracture toughness of 23 MPa m1/2 which is 80% of base metal fracture toughness. The superior tensile and fracture toughness properties of joints are mainly attributed to the evolution of finer grains in SZ due to the stirring action of FSW tool.

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Li, Juan, Honglong Zhao, Nian Zhou, Yingzhe Zhang, Qingdong Qin, Daoyi Wang, Jianguo Jiao, Guoli Tang e Yonghua Li. "Study on Microstructure of Fiber Laser Welding of CoCrCuFeNi High Entropy Alloy". Materials 15, n. 24 (8 dicembre 2022): 8777. http://dx.doi.org/10.3390/ma15248777.

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A CoCrCuFeNi high-entropy alloy was successfully welded in this study using fiber laser welding. The effects of the welding parameters on the microstructure and mechanical properties were studied. Three zones were formed: the fusion zone, partial melting zone, and base metal. The base metal exhibited a typical dendrite structure, and the Cu element segregated in the interdendrite. The fusion zone consisted of fine equiaxed crystals and columnar crystals with the same crystalline structure as the base metal. The fusion zone exhibited minimal compositional microsegregation after laser welding. Electron backscatter diffraction results showed that the low-angle grain boundary fraction in the fusion zone increased. Furthermore, some dislocations and dislocation pile-ups were present in the fusion zone, and the densities of the dislocations and dislocation pile-ups were higher than those of the base metal. The hardness of the fusion zone was considerably higher than that of the base metal, while the ultimate tensile strength and elongation values were lower than those of the base metal for all conditions. The ultimate tensile strength and the elongation increased gradually and then decreased with increasing laser power. The maximum ultimate tensile strength exceeded that of the base metal by 90%.

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Più fonti

Tesi sul tema "Tensile zone"

Perng, Jia-Der. "Analysis of crack propagation in asphalt concrete using a cohesive crack model". Connect to this title online, 1989. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1094737677.

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Brahmachari, Koushik, of Western Sydney Hawkesbury University, of Science Technology and Agriculture Faculty e School of Construction and Building Sciences. "Connection and flexural behaviour of steel RHS filled with high strength concrete". THESIS_FTA_CBS_BRAHMACHARI_K.xml, 1997. http://handle.uws.edu.au:8081/1959.7/526.

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Steel hollow section members filled with concrete have been frequently used in recent construction industry as columns and beams and beam-columns because of their superior performance and constructability. Previous research demonstrated that such system has large energy absorption capacity which is critical in the event of an earthquake. By filling steel RHS with concrete, the failure of the steel shell due to local buckling can be delayed and the ductility of the concrete core can be improved as a result of the confinement of the steel shell. This type of composite section may be used in various structures including frames of high rise buildings, bridges, offshore structures, cast-in-situ piles in foundation etc. Design methods for concrete-filled steel tubular sections are recommended in a number of code of practices. Due to the significant differences in the material properties between normal strength concrete and high strength concrete, there is a need to study the behaviour of composite sections with higher strength concretes. The study emphasises ultimate strength, ductility, post-failure strength reserve and interface bond. It also emphasises ductility and post-failure strength of the composite beams due to the brittle behaviour of higher strength concretes when compared to normal strength concrete. Spreadsheet graph were used to present the results such as load versus strains, load versus deflections etc. In this thesis analytical study is presented on the calculation of ultimate moment of resistance of the concrete-filled RHS beams. Among the main considerations of the derivation, the steel portion was assumed either elastic-perfectly plastic or perfectly plastic and concrete carries no strength in the tensile zone. At the interface both full bond and partial bond were assumed for comparison. Efforts were also made to calculate the midspan deflections of the composite beams. Simple analytical expressions derived from this study can be coded to a prgrammable calculator or in a small spreadsheet program for design use. Finite element studies were carried out by using a proprietorship software package ANSYS. In the analysis of concrete-filled, three types of elements with large deformation and nonlinear capabilities were used. A plastic shell element, a solid concrete element with cracking and crushing capabilities, and a nonlinear spring contact element were used to model the steel shell, the concrete core and the interface respectively.
Doctor of Philosophy (PhD)

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Lolla, Sri Venkata Tapasvi. "Understanding the Role of Initial Microstructure on Intercritically Reheated Heat Affected Zone Microstructure and Properties of Multi-Pass Welds". The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1397826410.

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Cristea, Alex Florian. "Analysis of thermal effects in circumferential groove journal bearings with reference to the divergent zone". Thesis, Poitiers, 2012. http://www.theses.fr/2012POIT2313/document.

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Ce travail porte sur l'étude des effets thermiques dans un palier hydrodynamique, alimentée par une rainure circonférentielle (CGJB) sous charge statique, en tenant compte des phénomènes de rupture de film dans la zone divergente. La recherche expérimentale a été réalisée à l'Université de Poitiers ; elle a permis une détermination minutieuse des champs de pression et de température sur la portée située à l’avant d’un CGJB et dans la section médiane de sa rainure. Ces mesures sous un régime stationnaire sont originales par rapport celles existantes, quel que le type de palier, de par le grand nombre de points de mesure, 180 pour la pression et 144 pour la température, l'instrumentation de haute précision, la large plage de conditions d'exploitation (pression spécifique variant de 0,125 à 2 MPa et vitesse linéaire de l’arbre allant de 5,25 à 21 m/s). Des études du régime transitoire de démarrage au régime stationnaire établi ont été effectuées pour de faibles charges. Des expériences effectuées à l'Université "Politehnica" de Bucarest ont montré une bonne corrélation entre la perte de portance, anti-portance et la rupture du film sur un patin Rayleigh (RSP), ce qui est essentiel pour l'évaluation des phénomènes de rupture dans les paliers. Quelques modèles théoriques ont été utilisés pour évaluer les risques de serrage au démarrage qui est une instabilité thermoélastique catastrophique. Les principaux résultats sont l’obtention d’une base fiable de données expérimentales permettant le développement des modèles théoriques avancés et l’infirmation d’une répartition de pression constante dans la zone divergente et de pression et température constantes dans la rainure d'alime
The main objective of the thesis is to study the thermal effects in steadily loaded circumferential groove journal bearings (CGJBs), including cavitation phenomena occurring in the divergent zone of such bearings. Experimental research conducted at University of Poitiers – Institut Pprime – France enabled a thorough determination of film pressure and temperature fields for the front land of a CGJB plus its mid-groove section, and several performance parameters. Measurements of film pressure and temperature fields under steady-state regime surpassed existing works, regardless of journal bearing design, through: sheer number of land measurement locations, 180 for pressure and for 144 temperature; high precision state of art instrumentation; broad range of operating conditions, 0.125 … 2 MPa specific bearing pressure and 5.25 … 21 m/s shaft speeds. Transient start-up to steady-statestabilization regimes have been investigated at low loads. Experiments at University "Politehnica" of Bucharest – Romania showed a correlation between the downforce thrust and film rupture for a Rayleigh step pin (RSP), important in evaluating divergent zone cavitation phenomena. Theoretical research consisted in developing simple models for evaluating CGJBs performance in steady-state and transient start-up regimes. Several theoretical models were employed for assessing start-up seizure, catastrophic transient thermoelastic instability and damage risk. The major result is a reliable experimental data collection that: enables development of advanced theoretical models; disprove flat film pressure distributions in divergent zones, and constant pressure and temperature in the bearing supply groov

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Brahmachari, Koushik. "Connection and flexural behaviour of steel RHS filled with high strength concrete". Thesis, View thesis, 1997. http://handle.uws.edu.au:8081/1959.7/526.

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Kejík, Vít. "Predikce chování stříkaného betonu s využitím elastoplastického materiálového modelu". Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2020. http://www.nusl.cz/ntk/nusl-409748.

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This work is focused on the application of advanced elasto-plastic material model intended for shotcrete. Spatial mathematical models of two laboratory tests are created, where this model is used. The first test is a three-point bending concrete specimen. Next, the behavior of the material is analyzed, in which input parameters are entered. Consequently, two reverse analyzes of the available data are analyzed where a match between prediction and measurement can be obtained. The second test is a modified tensile test, where is describe the material behavior in changing of input parameters. Subsequently, reverse data analysis is created, where an acceptable match between prediction and measurement is possible. In every study, the stress waveform in the fracture process zone is analyzed to more detail.

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Ben, Salem Naoufel. "Fiabilité des assemblages structuraux collés pour applications spatiales". Thesis, Bordeaux 1, 2012. http://www.theses.fr/2012BOR14681/document.

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Le dimensionnement des joints collés est une préoccupation majeure du CNES pour lesapplications spatiales des futurs lanceurs. Pour dimensionner une structure collée, il est nécessaire depouvoir apprécier les caractéristiques mécaniques du joint collé.Dans cette étude, trois adhésifs structuraux ont été sélectionnés (Hysol®EA 9321, Hysol®EA9394 et Hysol EA® 9395). Après leur caractérisation massique, une étude statistique pour mettre enévidence les effets des différents paramètres (vitesse d’essai, géométrie éprouvette, le degré depolymérisation…) a été entreprise.La deuxième étape a pour objectif de fiabiliser l’analyse des essais de fissuration etd’améliorer la compréhension des mécanismes d’endommagement et de propagation de fissure dansles liaisons collées. Trois types d’essai ont été utilisés, à savoir, l’essai Double Cantilever Beam(DCB), pour l’étude du mode I, l’essai End Notched Flexure (ENF), pour le mode II, et l’essai MixedMode Bending (MMB), pour les chargements en mode mixte I/II. Nous avons développé de nouvellesinstrumentations et méthodologies d’analyse. Pour affiner le protocole de test standard, la techniquedite de « backface strain monitoring » a été utilisée. Elle consiste à positionnées des jauges dedéformation sur les surfaces de l’éprouvette de façon à enregistrer l’évolution du signalextensométrique durant la propagation de la fissure. Cette méthode permet une meilleure estimation dela position front de fissure ainsi que l'étude de la répartition des contraintes le long du joint de colle.La corrélation d'images numériques (DIC) a également été utilisée afin de proposer un nouveauprotocole de calibrage de la longueur de fissure et pour comparer un modèle analytique (poutre deTimoshenko sur fondation élastique) avec les résultats expérimentaux
Adhesive bonding is being strongly considered in space applications CNES as anadvantageous assembly technique for future launchers. Correct design of adhesive joints is of majorconcern. Aerospace adhesives are tough viscoelastic matrices (special epoxy resins) reinforced withnano-, or microparticles. Extended use of adhesive joints in structural applications is limited due to thedifficulties in predicting in-service performance, frequently leading to over-conservative design.Three structural adhesives (Hysol®EA 9321, Hysol®EA 9394 and Hysol®EA 9395) wereselected. After their bulk characterization, statistical studies to highlight effects of different parameterse.g. speed, test piece geometry, degree of polymerization were undertaken.In the second stage, fracture mechanics tests were effected employing: the double cantileverbeam (DCB) configuration (mode I characterisation), the three point bending end-notched flexure(ENF) (mode II) and the mixed-mode bending (MMB) (combined mode I/II loading). Crack growth inbonded joints was investigated in a novel way. To refine standard test protocol, the backface strainmonitoring technique was used. Strain gauges were used to measure the strain on the exposed skin ofthe adherends during crack onset and propagation. This method allows better estimation of the crackfront position as well as fine investigation of the stress distribution along the bondline and in the crackfront vicinity. Digital image correlation (DIC) was also used to compare analytical models, e.g.Timoshenko beam on elastic foundation model with experimental results

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Nikpay, Mitra. "Experimental investigation of the stability of the colmation zone around leaky sewers". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-191137.

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Sewage exfiltration from a sanitary and combined sewer systems and its percolation into porous medium results in a clogged or colmation layer in the nearby soil. In order to develop a comprehensive understanding of raw sewage transport mechanisms in porous media, investigations were carried out on the micro-scale properties of the multiphase system. In our laboratory experiments, the role of surfactants as a major organic chemical compound in wastewater was evaluated by using a surfactant solution as an artificial wastewater percolating into a porous media, represented by using columns and Plexiglas model. We studied flows of water and surfactants solution in saturated porous medium to detect the dynamic effects by means of measuring pressure and permeability as well as by visualization of flow regions and consequence for porosity along interfaces between water and surfactants solution. The tests revealed that mechanisms at interfaces between fluids and solids as well as between water and surfactants solution (i.e. wastewater) are significantly influencing the flow behavior. At the interfaces surfactant molecules are adsorbed or accumulate, respectively, and subsequently inducing electrical charges to those layers, altering the properties of fluids and these interfaces. Depending on the conditions, channels might be narrowed and thus decreasing the flow rate with a later erosion and increase of flow rates, or the flow and thus the erosive capacity might become intensified along the interface between surfactants solution and neighbouring water. In conclusion, the results of tests proved the surfactants to be an important controlling factor in the hydraulic properties of wastewater percolating into soil.

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Raiss, Mark Edward. "Observation of the development of fracture process zones in concrete under tension". Thesis, Imperial College London, 1987. http://hdl.handle.net/10044/1/47748.

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Lookingbill, Scott David, e Scott David Lookingbill. "Effects of concentration-dependent surface tension on vadose zone instrumentation". Thesis, The University of Arizona, 1997. http://hdl.handle.net/10150/626774.

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Many of the organic compounds of environmental interest which are commonly found at contaminated sites have the effect of lowering the surface tension of water in proportion to their aqueous concentration. Laboratory studies were conducted to investigate the effects of reduced surface tension on instruments commonly used to measure pressure head in the vadose zone. Gypsum block electrical resistance sensors and heat dissipation probes were calibrated in tap water and in butanol solutions. A scaling relationship was used to correct pressure head measurements taken in liquids of reduced surface tension. The results indicate that the these measurements would be in error in that they would underestimate pressure head for solutions of lower surface tension to the same factor by which surface tension was reduced. This would result in pressure head gradient and flux being underestimated as well. Therefore, surface tension effects on these instruments should be considered when measuring pressure head in soils contaminated with organic compounds.

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Più fonti

Libri sul tema "Tensile zone"

Low Temperature Tensile Properties of Zone Refined Niobium. Hassell Street Press, 2021.

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The Tension Zone. Four Way Books, 1996.

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Wang, Ming-che. In-situ evaluation of capillary wick tension in wick lysimeters for sampling from vadose zone. 1993.

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Wang, Ming-che. In-situ evaluation of capillary wick tension in wick lysimeters for sampling from vadose zone. 1993.

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Gray, W. Malcolm. Ductile Fracture of Gas Pipelines: Correlation Between Fracture Velocity and Plastic Zone Defined from Tension Test Parameters. Amer Gas Assn, 1985.

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Spielman-Davidson, Sylvia Justina. Collaborative dialogues in the zone of proximal development: Grade eight French immersion students learning the conditional tense. 2000.

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Mayntz, Renate. Illegal Markets. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198794974.003.0002.

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The study of illegal markets needs to distinguish illegality from legality, and to relate both to legitimacy. There is no conceptual ambiguity about the distinction between legal and illegal if legality is formally defined. In practice, (formal) legality and (social) legitimacy can diverge: illegal markets are empirically related to organized crime, mafia, and even terrorist organizations, and they interact both with legal markets and the forces of state order. Where legal and illegal action systems are not separated by clear social boundaries, they are connected by what has come to be called “interfaces”: actors moving between a legal and an illegal world, and grey zones of actions that are neither clearly legal or illegal, nor clearly legitimate or illegitimate. Interfaces facilitate interaction between legal and illegal action systems, but they are also sources of tension and can lead to institutional change.

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Haines, Daniel. Rivers Divided. Oxford University Press, 2017. http://dx.doi.org/10.1093/acprof:oso/9780190648664.001.0001.

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The Indus Waters Treaty is considered a key example of India–Pakistan cooperation, but less has been said about its critical influence on state-making in both countries. This book reveals the importance of the Indus Basin river system, and thus control over it, for Indian and Pakistani claims to sovereignty after South Asia’s Partition in 1947. Securing water flows was a key aim for both governments. In 1960 the Indus Waters Treaty ostensibly settled the dispute, but in fact failed to address critical sources of tension. Examples include the role of water in the Kashmir conflict and the riverine geography of Punjab’s militarized border zone. Despite the recent resurgence of disputes over water-sharing in South Asia, the historical causes and consequences of the region’s flagship natural resources treaty remain little understood. Based on new research in South Asia, the United States and United Kingdom, this book places the Indus dispute, for the first time, in the context of decolonization and Cold War-era development politics. Using perspectives from environmental history, political geography, and international relations, it examines the discord over riparian rights at local, national and international levels, arguing that we can only explain its importance and longevity in light of India and Pakistan’s state-building initiatives after independence. In the process, it puts forward a new reading of territoriality in South Asia.

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Clarkson, Carrol. ‘Wisselbare Woorde’. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198805281.003.0012.

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Carrol Clarkson’s chapter wrestles with the contentious question of Coetzee’s relation to the Black Consciousness Movement in South Africa of the 1970s and early 1980s, which took its philosophical bearings from Frantz Fanon and found expression in the writings of Steve Biko. Clarkson focuses on the ways in which Coetzee departed from the ideas about writing and resistance that were circulating in his contemporary South Africa, particularly as articulated by novelist Nadine Gordimer. Clarkson discusses two related literary-critical problems: an ethics and politics of representation, and an ethics and politics of address, showing how Coetzee explores a tension between freedom of expression and responsibility to the other. In the slippage from saying to addressing we are led to further thought about modes and sites of consciousness—and hence accountabilities—in the interlocutory contact zones of the post-colony. The chapter invites a sharper appreciation of what a postcolonial philosophy might be.

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Renic, Neil C. Asymmetric Killing. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780198851462.001.0001.

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This book offers an engaging and historically informed account of the moral challenge of radically asymmetric violence—warfare conducted by one party in the near-complete absence of physical risk, across the full scope of a conflict zone. What role does physical risk and material threat play in the justifications for killing in war? And crucially, is there a point at which battlefield violence becomes so one-directional as to undermine the moral basis for its use? In order to answers these questions, Asymmetric Killing delves into the morally contested terrain of the warrior ethos and Just War Tradition, locating the historical and contemporary role of reciprocal risk within both. This book also engages two historical episodes of battlefield asymmetry, military sniping and manned aerial bombing. Both modes of violence generated an imbalance of risk between opponents so profound as to call into question their permissibility. These now-resolved controversies will then be contrasted with the UAV-exclusive violence of the United States, robotic killing conducted in the absence of a significant military ground presence in conflict theatres such as Pakistan, Yemen, and Somalia. As will be revealed, the radical asymmetry of this latter case is distinct, undermining reciprocal risk at the structural level of war. Beyond its more resolvable tension with the warrior ethos, UAV-exclusive violence represents a fundamental challenge to the very coherence of the moral justifications for killing in war.

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Capitoli di libri sul tema "Tensile zone"

Tse, A., E. Shin, A. Hiltner e E. Baer. "The Damage Zone in Some Ductile Polymers under a Triaxial Tensile Stress State". In Advances in Chemistry, 143–60. Washington, DC: American Chemical Society, 1993. http://dx.doi.org/10.1021/ba-1993-0233.ch006.

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Adlakha, I., K. N. Solanki e M. A. Tschopp. "Influence of Grain Boundary Structure on Interfacial Fracture Under Tensile Loading: Cohesive Zone Model Informed by Atomistic Simulations". In TMS2013 Supplemental Proceedings, 753–58. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2013. http://dx.doi.org/10.1002/9781118663547.ch93.

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Sano, Tomoko, Jian Yu, Richard Chen e Chian-Fong Yen. "The Effect of the Variation of Microstructure in the Friction Stir Welded Zone on the Strain and Tensile Properties of Al2139". In ICAA13: 13th International Conference on Aluminum Alloys, 653–58. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2012. http://dx.doi.org/10.1002/9781118495292.ch95.

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Sano, Tomoko, Jian Yu, Richard Chen e Chian-Fong Yen. "The Effect of the Variation of Microstructure in the Friction Stir Welded Zone on the Strain and Tensile Properties of Al2139". In ICAA13 Pittsburgh, 653–58. Cham: Springer International Publishing, 2012. http://dx.doi.org/10.1007/978-3-319-48761-8_95.

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Wang, Chi-Yuen, e Michael Manga. "Groundwater Level". In Lecture Notes in Earth System Sciences, 155–200. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-64308-9_6.

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AbstractGroundwater level has long been known to respond to earthquakes; several types of response have been documented. Advances in the last decade were made largely through the studies of water-level response to Earth tides and barometric pressure. These studies have demonstrated that the hydraulic properties of groundwater systems are dynamic and change with time in response to disturbances such as earthquakes. This approach has been applied to estimate the permeability of several drilled active fault zones, to identify leakage from deep aquifers used for the storage of hazardous wastewater, and to reveal the potential importance of soil water and capillary tension in the unsaturated zone. Enhanced permeability is the most cited mechanism for the sustained changes of groundwater level in the intermediate and far fields, while undrained consolidation remains the most cited mechanism for the step-like coseismic changes in the near field. A new mechanism has emerged that suggests that coseismic release of pore water from unsaturated soils may also cause step-like increases of water level. Laboratory experiments show that both the undrained consolidation and the release of water from unsaturated zone may occur to explain the step-like water-level changes in the near field.

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Huang, Ming Li, Tao Xu, Fei Wang e Wan Cheng Zhu. "Numerical Simulation of Fracture Process Zone in Concrete Tension Specimen". In Key Engineering Materials, 1045–48. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-456-1.1045.

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Paul, Sharad P. "Anatomical Considerations During Cutaneous Surgery on the Face: Skin Biodynamics, Neurovascular Zones and BEST Lines". In Biodynamic Excisional Skin Tension Lines for Cutaneous Surgery, 155–72. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-71495-0_11.

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Sharonova, Svetlana A., Natalia S. Erokhova, María Angélica Oliva e Márcia Lopes Reis. "System of Interaction Between Global Education and the National System of Education: A Social Tension Zone". In Intercultural Studies in Higher Education, 55–78. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-15758-6_3.

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Borysiuk, Oleksandr, e Yuriy Ziatiuk. "Experimental Research Results of the Bearing Capacity of the Reinforced Concrete Beams Strengthened in the Compressed and Tensile Zones". In Lecture Notes in Civil Engineering, 63–70. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-57340-9_8.

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Carpinteri, Alberto, e Marco Paggi. "Modelling Strain Localization by Cohesive (Overlapping) Zones in Tension (Compression): Brittleness Size Effects and Scaling in Material Properties". In Mechanics Down Under, 15–33. Dordrecht: Springer Netherlands, 2013. http://dx.doi.org/10.1007/978-94-007-5968-8_2.

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Atti di convegni sul tema "Tensile zone"

Bardelcik, Alexander, Ryan George e Michael J. Worswick. "Transition Zone Tensile Properties within a Tailored Hot Stamping". In SAE 2012 World Congress & Exhibition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2012. http://dx.doi.org/10.4271/2012-01-0531.

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Kang, Seung-Kyun, Young-Cheon Kim, Chan-Pyoung Park e Dongil Kwon. "Evaluation of Tensile Properties Profile of Weld Zone Using Instrumented Indentation". In ASME 2010 Pressure Vessels and Piping Division/K-PVP Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/pvp2010-25848.

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Understanding the property distribution in the weld zone is very important for structural safety, since deformation and fracture begin at the weakest point. However, conventional tensile tests can measure only average material properties because they require large specimens. Small-scale tests are being extensively researched to remove this limitation, among such tests, instrumented indentation test (IIT) are of great interest because of their simple procedures. Here we describe the evaluation of tensile properties using IIT and a representative stress-strain approach. The representative stressstrain method, introduced in 2008 in ISO/TR29381, directly correlates the stress and strain under the indenter to the true stress and strain of tensile testing by defining representative functions. Using this technique, we successfully estimate the yield strength and tensile strength of structural metallic materials and also obtain profiles of the weld-zone tensile properties.

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Fukuda, Yuka, Osamu Saito, Satoru Aoike e Fuminori Iwamatsu. "Development of Stress Reduction Method in the Pipe Welded Zone". In ASME 2009 Pressure Vessels and Piping Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/pvp2009-77901.

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Stress Corrosion Cracking (SCC) failures have occurred in the vicinity of austenitic stainless steel pipe welds used in boiling water reactors, since the late 70s. One of the initial countermeasures against SCC has been to use low-carbon stainless steel. However, in older plants, SCC failures in low-carbon stainless steel pipe were still observed in recent years. It is well understood that residual tensile stress due to welding largely affects occurrence and growth of SCC in low-carbon stainless steel. Because of this, it is important to reduce the residual tensile stress in the welded zone in addition to utilizing less susceptible material. However, a countermeasure to reduce residual tensile stress in small-bore pipe has not been established. In this study, a new stress reduction method is developed in order to reduce residual tensile stress in the welded zone, even for small-bore pipe. This method is applied to the butt-welded zone while the pipe is filled with water. First, the pipe is frozen at two points centering around the welded zone by cooling the outer surface of the pipe to transform the water to plugs of ice. The volume inside the pipe between the ice plugs becomes watertight and pressurized by the expansion of the plugs up-on freezing. The pipe expands near the zone of the weld groove, because the wall thickness of the butt-welded zone is thinner locally because of the weld counter bore. In this process, tensile strain occurs near the welded zone due to the pipe expansion beyond its plastic range, and then hoop tensile plastic strain of inner surface is larger than that of outer surface. Once the pressure load is removed, the difference in these tensile strains induces the hoop residual tensile stress on the inner surface to reverse to a compressive stress. On the other hand, the local bending deformation that occurs in the welded zone results in an axial residual compressive stress on inner surface. Both experimental studies and finite element analysis confirmed that the hoop and axial residual tensile stress at the inner surface of the welded zone are reversed to compressive stress by the pipe expansion.

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Khatib, Jamal, Ali Jahami e Ossama Baalbaki. "Flexural characteristics of reinforced concrete beams containing lightweight aggregate in the tensile zone". In Fifth International Conference on Sustainable Construction Materials and Technologies. Coventry University and The University of Wisconsin Milwaukee Centre for By-products Utilization, 2019. http://dx.doi.org/10.18552/2019/idscmt5170.

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Rekik, W., O. Ancelet e C. Gardin. "Identification of the Gradient of Mechanical Properties in Electron Beam Welded Joints of Thick Al6061-T6 Plate". In ASME 2016 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/pvp2016-63451.

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In this paper, the mechanical behavior of the different metallurgical zones of the Electron Beam welded joint of thick Aluminum alloy 6061-T6 plates was identified by means of a single tensile test on round specimen oriented transversely to the fusion line. Commonly, the analysis of tensile tests allows a global characterization of the weld joint behavior. However, in this work, specific post processing of results was developed in order to determine in addition to standard findings, the local behavior on each position of the weld joint. The identified behavior laws are then simplified using the Hollomon analytical model. Hence, an evolution of the Hollomon parameters (n, K) along the weld joint is proposed. To validate the experimental methodology and the analytical approach, the experimental tensile test on crossed tensile specimen was numerically modeled. Experimental results and numerical simulations were in a good agreement which denotes of the reliability of the identified gradient model. In a second step, for more accurate characterization of the electron beam welded joint, an optimized geometry of tensile specimen was numerically dimensioned and tested. From these analyses, a relatively large heat affected zone with significant gradients of mechanical properties was highlighted. The fusion zone was qualified as the softest metallurgical zone but with a high strain hardening effect in contrary with the heat affected zone where the fracture occurs.

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Mohamed Rafi, Afrith Noor, Mystica Augustine Michael Duke e Senthil Kumar Velukkudi Santhanam. "Microstructural Analysis and Tensile Property Studies on Spray Cooled Friction Stir Welded Aluminium Alloy 2014". In ASME 2021 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/imece2021-68012.

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Abstract Conventional Friction Stir Welding has increased heat generation which results in improper dissolution of precipitates in Heat Affected Zone (HAZ) which develop the weakest section of the weld. In order to dissipate the heat beyond Thermo-Mechanical Affected Zone (TMAZ), spray nozzle with water and compressed air is used in this study. Friction Stir Welding assisted with cooling has been shown to improve the microstructure properties of the weld than normal friction stir welding process (FSW). This is because the grain structures in the nugget zone become finer when water is used as a cooling medium to dissipate the excess heat. Refined grain structure is known to improve the tensile strength and ductile properties of the weld. The welding was carried out using the spray setup at 1000 rpm and 44 mm/min. The flow rate of the nozzle setup was set to 72 ml/min. The tensile behavior of the welded specimen was then tested. The ultimate tensile strength of water cooled was obtained and compared with air cooled weld. Fracture analysis was performed using Scanning Electron Microscope (SEM) and the results are then compared. Microhardness values of various zones were then measured and compared. It was found that the weld obtained with water cooled friction stir welding possesses balanced hardness and tensile properties suitable for real life applications.

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Bartan, Busra, Bülent Acar e Altan Kayran. "Three-Dimensional Delamination Analysis in Composite Open Hole Tensile Specimens with Cohesive Zone Method". In 57th AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference. Reston, Virginia: American Institute of Aeronautics and Astronautics, 2016. http://dx.doi.org/10.2514/6.2016-0980.

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Dinovitzer, A., D. Begg, M. Quintana e R. Lazor. "Heat Affected Zone Softening Susceptibility Test". In 2020 13th International Pipeline Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/ipc2020-9710.

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Abstract There have been a number of unexpected girth weld failures in pipelines, both in-service and during pre-service hydrostatic testing. Investigation of these incidents indicated that the line pipe met industry standard requirements, such as API 5L and the welding procedures had been qualified to API 1104 and construction welding/inspection had been completed according to industry standards. The investigation of these failures indicated that they were not related to hydrogen cracking or misalignment, however, line pipe chemical composition and tensile properties were identified as having contributed to these failures. Low carbon and low carbon equivalent (CE) higher strength line pipe materials produced with thermo-mechanical controlled processing (TMCP) practice is believed to have contributed to the failures. Higher heat input welding in these lean chemistry steels can result in heat affected zone (HAZ) softening that produces a lower strength zone adjacent to the girth weld, making it susceptible to tensile failure from axial loading. In the presence of thermal or geohazard loading, these softened or lower strength HAZ’s become a concern where there has been pipe settlement or in strain-based assessment. To understand the factors that influence the susceptibility to HAZ softening and identify those materials that can be considered at risk, a material testing procedure has been developed. This new testing procedure is a weld bead-in-plate test that was designed to maximize the potential for HAZ softening in an effort to identify those line pipe materials that may be susceptible to HAZ softening in construction or during in-service welding. This paper presents the results of experimental trials comparing the susceptibility of leaner chemistry materials to HAZ softening. The testing procedure is described along with opportunities to enhance the procedure to develop a standardized test for HAZ softening assessment. This test has the potential to be used to identify materials at risk to HAZ softening and may also be used to qualify line pipe to demonstrate its resistance to HAZ softening.

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Park, Seonghun, Ramaswamy Krishnan, Steven B. Nicoll e Gerard A. Ateshian. "Cartilage Interstitial Fluid Load Support in Unconfined Compression". In ASME 2002 International Mechanical Engineering Congress and Exposition. ASMEDC, 2002. http://dx.doi.org/10.1115/imece2002-32620.

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Under physiological conditions of loading, articular cartilage is subjected to both compressive strains, normal to the articular surface, and tensile strains, tangential to the articular surface. Previous studies have shown that articular cartilage exhibits a much higher modulus in tension than compression. Theoretical analyses have suggested that this tension-compression nonlinearity enhances the magnitude of interstitial fluid pressurization during loading in unconfined compression, above a theoretical threshold of 33% of the average applied stress. The first hypothesis of this experimental study is that the peak fluid load support in unconfined compression is significantly greater than the 33% theoretical limit predicted for porous permeable tissues modeled with equal moduli in tension and compression [1]. The second hypothesis is that the peak fluid load support is higher at the articular surface side of the tissue samples than near the deep zone, because the disparity between the tensile and compressive moduli is greater at the surface zone.

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Djebali, S., S. Larbi e A. Bilek. "Study of the plastic zone around the ligament of thin sheet D.E.N.T specimen subjected to tensile". In 4TH INTERNATIONAL CONGRESS IN ADVANCES IN APPLIED PHYSICS AND MATERIALS SCIENCE (APMAS 2014). AIP Publishing LLC, 2015. http://dx.doi.org/10.1063/1.4914223.

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Rapporti di organizzazioni sul tema "Tensile zone"

Carlson, John. Nuclear verification in a Middle East WMD-Free Zone: Lessons from Past Verification Cases and Other Precedents. The United Nations Institute for Disarmament Research, gennaio 2021. http://dx.doi.org/10.37559/wmdfz/21/nv/01.

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Verification will be of critical importance to achieving and maintaining a Middle East zone free of weapons of mass destruction (ME WMD). Effective verification arrangements would serve a vital national security objective for each state in the region by reducing tensions, removing the motivation to proliferate, and mitigating the risk of a virtual nuclear arms race (or war). In view of the high levels of tension and mistrust within the zone, ensuring effective verification will be especially demanding. The paper examines specific elements of the future nuclear verification of the zone, including: Which states should be included? What prohibitions and obligations should apply in the zone and how would they be verified? How could elimination of nuclear weapons in the zone be achieved? On what basis would the zone treaty enter into force? The paper also examines a number of existing treaties and arrangements as well as the lessons learned from past verification cases which regional states can draw on in developing verification for a Middle East nuclear-weapon-free zone.

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Shmulevich, Itzhak, Shrini Upadhyaya, Dror Rubinstein, Zvika Asaf e Jeffrey P. Mitchell. Developing Simulation Tool for the Prediction of Cohesive Behavior Agricultural Materials Using Discrete Element Modeling. United States Department of Agriculture, ottobre 2011. http://dx.doi.org/10.32747/2011.7697108.bard.

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The underlying similarity between soils, grains, fertilizers, concentrated animal feed, pellets, and mixtures is that they are all granular materials used in agriculture. Modeling such materials is a complex process due to the spatial variability of such media, the origin of the material (natural or biological), the nonlinearity of these materials, the contact phenomenon and flow that occur at the interface zone and between these granular materials, as well as the dynamic effect of the interaction process. The lack of a tool for studying such materials has limited the understanding of the phenomena relevant to them, which in turn has led to energy loss and poor quality products. The objective of this study was to develop a reliable prediction simulation tool for cohesive agricultural particle materials using Discrete Element Modeling (DEM). The specific objectives of this study were (1) to develop and verify a 3D cohesionless agricultural soil-tillage tool interaction model that enables the prediction of displacement and flow in the soil media, as well as forces acting on various tillage tools, using the discrete element method; (2) to develop a micro model for the DEM formulation by creating a cohesive contact model based on liquid bridge forces for various agriculture materials; (3) to extend the model to include both plastic and cohesive behavior of various materials, such as grain and soil structures (e.g., compaction level), textures (e.g., clay, loam, several grains), and moisture contents; (4) to develop a method to obtain the parameters for the cohesion contact model to represent specific materials. A DEM model was developed that can represent both plastic and cohesive behavior of soil. Soil cohesive behavior was achieved by considering tensile force between elements. The developed DEM model well represented the effect of wedge shape on soil behavior and reaction force. Laboratory test results showed that wedge penetration resistance in highly compacted soil was two times greater than that in low compacted soil, whereas DEM simulation with parameters obtained from the test of low compacted soil could not simply be extended to that of high compacted soil. The modified model took into account soil failure strength that could be changed with soil compaction. A three dimensional representation composed of normal displacement, shear failure strength and tensile failure strength was proposed to design mechanical properties between elements. The model based on the liquid bridge theory. An inter particle tension force measurement tool was developed and calibrated A comprehensive study of the parameters of the contact model for the DEM taking into account the cohesive/water-bridge was performed on various agricultural grains using this measurement tool. The modified DEM model was compared and validated against the test results. With the newly developed model and procedure for determination of DEM parameters, we could reproduce the high compacted soil behavior and reaction forces both qualitatively and quantitatively for the soil conditions and wedge shapes used in this study. Moreover, the effect of wedge shape on soil behavior and reaction force was well represented with the same parameters. During the research we made use of the commercial PFC3D to analyze soil tillage implements. An investigation was made of three different head drillers. A comparison of three commonly used soil tillage systems was completed, such as moldboard plow, disc plow and chisel plow. It can be concluded that the soil condition after plowing by the specific implement can be predicted by the DEM model. The chisel plow is the most economic tool for increasing soil porosity. The moldboard is the best tool for soil manipulation. It can be concluded that the discrete element simulation can be used as a reliable engineering tool for soil-implement interaction quantitatively and qualitatively.

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Thompson, M. L., R. L. Scharf e C. Shang. Zero-tension lysimeters: An improved design to monitor colloid-facilitated contaminant transport in the vadose zone. Office of Scientific and Technical Information (OSTI), aprile 1995. http://dx.doi.org/10.2172/108103.

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Warrick, Arthur, Uri Shani, Dani Or e Muluneh Yitayew. In situ Evaluation of Unsaturated Hydraulic Properties Using Subsurface Points. United States Department of Agriculture, ottobre 1999. http://dx.doi.org/10.32747/1999.7570566.bard.

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The primary information for accurately predicting water and solute movement and their impact on water quality is the characterization of soil hydraulic properties. This project was designed to develop methods for rapid and reliable estimates of unsaturated hydraulic properties of the soil. Particularly, in situ methodology is put forth, based on subsurface point sources. Devices were designed to allow introduction of water in subsurface settings at constant negative heads. The ability to operate at a negative head allows a direct method of finding unsaturated soil properties and a mechanism for eliminating extremely rapid preferential flow from the slow matrix flow. The project included field, laboratory and modeling components. By coupling the measurements and the modeling together, a wider range of designs can be examined, while at the same time realistic performance is assured. The developed methodology greatly expands the possibilities for evaluating hydraulic properties in place, especially for measurements in undisturbed soil within plant rooting zones. The objectives of the project were (i) To develop methods for obtaining rapid and reliable estimates of unsaturated hydraulic properties in situ, based on water distribution from subsurface point sources. These can be operated with a constant flow or at a constant head; (ii) To develop methods for distinguishing between matrix and preferential flow using cavities/permeameters under tension; (iii) To evaluate auxiliary measurements such as soil water content or tensions near the operating cavities to improve reliability of results; and (iv: To develop numerical and analytical models for obtaining soil hydraulic properties based on measurements from buried-cavity sources and the auxiliary measurements. The project began in July 1995 and was terminated in November 1998. All of the objectives were pursued. Three new subsurface point sources were designed and tested and two old types were also used. Two of the three new designs used a nylon cloth membrane (30 mm) arranged in a cylindrical geometry and operating at a negative water pressure (tension). A separate bladder arrangement allowed inflation under a positive pressure to maintain contact between the membrane and the soil cavity. The third new design used porous stainless steel (0.5 and 5 mm) arranged in six segments, each with its own water inlet, assembled to form a cylindrical supply surface when inflated in a borehole. The "old" types included an "off-the-shelf" porous cup as well as measurements from a subsurface drip emitter in a small subsurface cavity. Reasonable measurements were made with all systems. Sustained use of the cloth membrane devices were difficult because of leaks and plugging problems. All of the devices require careful consideration to assure contact with the soil system. Steady flow was established which simplified the analysis (except for the drip emitter which used a transient analysis).

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Martosudarmo, S. Y., A. M. Johnson e R. W. Fleming. Ground fracturing at the southern end of Summit Ridge caused by October 17, 1989 Loma Prieta, California, earthquake sequence (maps of Summit Ridge Shear Zones, en echelon tension cracks, complex and compound fractures, and small faults that formed coactively with the earthquake sequence). Office of Scientific and Technical Information (OSTI), dicembre 1997. http://dx.doi.org/10.2172/677053.

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NUMERICAL SIMULATION AND RESEARCH ON WELDING RESIDUAL STRESS OF BOX - TYPE STEEL STRUCTURE. The Hong Kong Institute of Steel Construction, agosto 2022. http://dx.doi.org/10.18057/icass2020.p.324.

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The welding residual stress of the box-plate steel structure is studied in this paper. Q235B steel and Q345B steel are generally used in box plate assembly steel structures, so this paper focuses on the welding residual stress of these two sheets of steel. The welding of Q235B and Q345B steel plates was simulated by ABAQUS associated DFLUX heat source subroutine. The welding residual stress of the steel plates is tested by the ultrasonic testing method. The results show that the yield strength of steel has a significant effect on the welding residual stress. The longitudinal residual stress in the heataffected zone of the weld is mainly strength stress, while the transverse residual stress in the whole welding part is both tensile stress and compressive stress. The results of the steel plate residual stress test are in good agreement with the simulation results, which verifies the reliability of ABAQUS simulated steel plate welding.

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Comparison of mechanical behavior between longitudinal lap-welded joints and transverse fillet welded joints of high strength steel. The Hong Kong Institute of Steel Construction, agosto 2022. http://dx.doi.org/10.18057/icass2020.p.302.

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Mechanical behavior of twenty-eight longitudinal lap-welded joints made of high strength steels (HSS) under tension load was investigated by experimental study. Weaknesses due to traditional deformation measurements for fillet welded joints can be perfectly solved by digital image correlation techniques (DIC). The effect of parameters (e.g. weld size, weld length and mismatch ratio) on mechanical properties (e.g. ultimate strength, failure modes, weld ductility and fracture angle) of longitudinal fillet welds and transverse fillet welds, which was introduced in detail in previous work by the authors, were compared. Generally, because of the difference on the combination of shear force and tension force, the fracture angle of longitudinal welded specimens (around 50) were much more divergent from transverse welded specimens (around 20) even though both of them failed at welded zone (welded zone only refers to weld metal in this paper), resulting that the mean strength of longitudinal welded specimens were only 0.58 time of transverse welded specimens. Conversely, the mean deformation capacity of longitudinal welded specimens was almost 4.0 times of transverse welded specimens. Moreover, it was confirmed that the predicted loads of EC3 and AISC Specification were close and slightly conservative for all specimens.

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