Contact mechanical characteristics of Nb3Sn strands under transverse electromagnetic loads in the CICC cross-section

Harmonic gear reducer is widely used in industrial robots, aerospace, optics, and other high-end fields. The failure of harmonic gear reducer is mainly caused by the damage of flexible bearing and flexspline of thin-walled vulnerable components. To study the contact mechanical characteristics of flexible components such as flexible bearing and flexspline in harmonic gear reducer, the contact mechanical model of flexible bearing, vibration differential equation of flexspline, and finite element model of each component in harmonic gear reducer were established. Based on the established model of harmonic gear reducer, the influence of the length of flexspline cylinder and the thickness of cylinder bottom on the stress of flexspline is discussed, respectively, and the motion characteristics of flexible bearing are studied. At the same time, the spatial distribution of the displacement of the flexspline and the axial vibration response of the flexspline are studied. The correctness of the model established in this paper is verified by experiments. The results show that the increase of cylinder length can improve the stress of flexspline in harmonic gear reducer; the wall thickness of cylinder bottom mainly affects the stress at the bottom of flexspline but has little effect on the stress of gear ring and smooth cylinder. Along the axis direction of the flexspline, the radial displacement, circumferential displacement, and angular displacement increase linearly with the increase of the axial distance between the cylinder and the bottom. When the excitation frequency is high, the vibration mode of flexspline shell is mainly axial vibration. The research results will provide a theoretical reference for the optimal design of harmonic gear reducer and improving the service life of flexible parts.

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Analysis for bearing performance and construction mechanical behavior of supporting structure for the large cross-section tunnel by half bench CD method

PLoS ONE ◽

10.1371/journal.pone.0255511 ◽

2021 ◽

Vol 16 (8) ◽

pp. e0255511

Author(s):

Rui Zhao

Keyword(s):

Cross Section ◽

Mechanical Characteristics ◽

Internal Force ◽

Calculation Model ◽

Large Cross Section ◽

Support Structure ◽

Supporting Structure ◽

Bending Strain ◽

Excavation Process ◽

Deformation Distribution

Based on the engineering practice of large cross-section highway tunnel, this paper reveals the space-time coordinated evolution law of the construction mechanical characteristics and deformation distribution of the support structure in the construction by half bench CD method through field test. At the same time, the mechanical response calculation model of the supporting structure in the partial excavation is constructed, and the mechanical characteristics of the support structure in the partial excavation process are analyzed by above mechanical calculation model. Then, the mechanical and deformation distribution of the feet-reinforcement bolt in the steel frame—foot-reinforcement bolt combined support system is analyzed under different levels of surrounding rock load and different structural parameters of the feet-reinforcement bolt. The research results show that: (1) The internal force of the supporting structure changes most obviously during the excavation of Part Ⅰ, Part Ⅱ and Part Ⅲ, and the internal force of the support structure gradually tends to be stable after a slight increase in the excavation of Part Ⅳ and Part Ⅴ; (2) The horizontal deformation and vertical deformation of the support structure mainly occur in the excavation process of Part Ⅰ, Part Ⅱ and Part Ⅲ, and the excavation of Part Ⅳ and Ⅴ has little effect on the deformation response of the structure. The vertical displacement of the supporting structure is larger than the horizontal displacement, and the dynamic response of the temporary diaphragm structure during tunnel excavation is shrinkage-expansion-shrinkage-expansion; (3) The bending strain of each measuring point decreases with the increase of the distance from the loading point, and the bending strain of section 1 and section 2 is much larger than that of the other three sections; (4) With the increase of the angle, the section position with strain close to 0 gradually moves to the deeper position of the bolt, and the axial strain of each section on the bolt gradually changes from positive strain to negative strain.

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Nonlinear Finite Element Analysis on Frame Joints of Steel Truss SRC Beam

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.243-249.229 ◽

2011 ◽

Vol 243-249 ◽

pp. 229-234 ◽

Cited By ~ 1

Author(s):

Guang Xian Tang ◽

Zhi Chao Jia ◽

Zhi Heng Deng ◽

He Yong Lu

Keyword(s):

Cross Section ◽

Mechanical Characteristics ◽

Joint Damage ◽

Shear Capacity ◽

Nonlinear Finite Element ◽

Axial Loads ◽

Element Analysis ◽

Steel Truss ◽

Concrete Damage ◽

Test Result

To understand mechanical characteristics of frame joints of steel truss SRC beam, the accuracy of the proposed method is proved by the comparison between FEA result and test result, considering different steel ratios, cross flank rods and axial loads as well as plastic model of concrete damage. The result indicates that cross section and steel can delay joint damage and improve the bearing capacity, and that axial load can improve joints shear capacity to some extent but joints ductility is decreased, and that constraint of steel to concrete improves brittleness character caused by bad ductility of concrete.

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Research Progress on Steel-Concrete Composite Bridge Towers

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.250-253.2392 ◽

2011 ◽

Vol 250-253 ◽

pp. 2392-2395

Author(s):

Qian Wang ◽

Chun Sheng Wang ◽

Xin Xin Wang

Keyword(s):

Cross Section ◽

Composite Structure ◽

Mechanical Characteristics ◽

Research Progress ◽

Relevant Research ◽

Application Form ◽

Composite Bridge ◽

Steel Panels ◽

Bridge Tower ◽

Core Concrete

With the development of the steel-concrete composite structure, it has been found the new application form: steel-concrete composite bridge tower. Compared with the traditional concrete filled steel tubular column, composite bridge tower has connectors between steel panels and core concrete. Therefore, the mechanical characteristics of the composite tower are somewhat different with that of the composite column with no connectors. Some researches have been done on the composite tower and relevant research progress is introduced in this paper, which including the researches on composite bridge towers with different cross section types and with different connector types between steel panels and concrete.

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Improvement of the Mechanical Properties of Formed Steel Cross Section Profile for Timber Upgrading

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.498.139 ◽

2012 ◽

Vol 498 ◽

pp. 139-144

Author(s):

C. González-Bravo ◽

J. Claver ◽

R. Álvarez ◽

Rosario Domingo

Keyword(s):

Mechanical Properties ◽

Finite Element Method ◽

Finite Element ◽

Cross Section ◽

Manufacturing Process ◽

Mechanical Characteristics ◽

Section Profile ◽

Cold Formed Steel ◽

Deform 2D ◽

Cross Section Profile

The main objective of this paper is to analyze the behaviour of cold formed steel cross section respect to mechanical characteristics, such as deflection, mainly. A cold formed steel profile with thickness of 1 mm regards is studied to determine its viability as reinforcement of timber upgrading. Thus, temperatures, stresses and strains have been analysed during the manufacturing process of these profiles, and also, the deflection supported, comparing between unreinforced and reinforce pieces. The analysis has been carried out by means of Finite Element Method, using DEFORM 2D software, during the simulation of manufacturing process and COPRA software during the final static computations. Results provide information about the integrity and good behavior of these profiles for timber upgrading.

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Управление физико-механическими характеристиками бетона за счет варьирования высоты и шага технологических выступов хомутов виброцентрифугирующих устройств

ВЕСТНИК ИНЖЕНЕРНОЙ ШКОЛЫ ДВФУ ◽

10.24866/2227-6858/2021-1-12 ◽

2021 ◽

Vol 46 (1) ◽

Author(s):

Keyword(s):

Tensile Strength ◽

Compressive Strength ◽

Cross Section ◽

Mechanical Characteristics ◽

Experimental Studies ◽

Strength Analysis ◽

Technological Parameters ◽

Axial Tensile ◽

Concrete Mix ◽

Physical And Mechanical Characteristics

Для регулирования вариатропной структуры центрифугированных изделий авторы данной статьи совместили процесс центрифугирования с вибрированием. Во время эксперимента вибрации формы обеспечивались за счет надетых на валы установки хомутов. Представлена авторская экспериментальная установка для создания виброцентрифугированных образцов кольцевого сечения с вариатропной структурой, а также способ их изготовления. Выделены технологические параметры вибрирования, которые оказывали наиболее значимое влияние на характеристики виброцентрифугированного бетона, конструкций и изделий из него. В опытах варьировались высота технологических выступов хомутов и шаг между ними. Исследовалось влияние этих факторов на физико-механические характеристики бетона: плотность; кубиковая прочность на сжатие; призменная прочность на сжатие; прочность на растяжение при изгибе; прочность на осевое растяжение. Приведен анализ результатов экспериментальных исследований и получены следующие физико-механические характеристики виброцентрифугированных бетонов, изготовленных с использованием хомутов: лучшие – с высотой технологических выступов 5 мм и шагом между ними 30 мм, самый низкий показатель – соответственно 2,5 мм при любом шаге. Ключевые слова: виброцентрифугированный бетон, физико-механические характеристики, прочность при сжатии, плотность, бетонная смесь, центрифугирование, прочность при изгибе To regulate the variatropic structure of centrifuged products, the authors of this article combined the process of centrifugation with vibration. During the experiment, vibrations of the mold were provided with clamps set on the shafts of the installation. The author's experimental setup for creating vibrocentrifuged samples of annular cross-section with a variatropic structure, as well as a method for their manufacture is presented. The technological parameters of vibration, which had the most significant effect on the characteristics of vibrocentrifuged concrete, structures and products made of it, were identified. In the experiments, the height of the technological protrusions of the clamps and the pitch between them were varied. The influence of these factors on the physical and mechanical characteristics of concrete was investigated: density; cube compressive strength; prismatic compressive strength; bending tensile strength; axial tensile strength. Analysis of the results of experimental studies is given and the following physical and mechanical characteristics of vibrocentrifuged concretes made using clamps have been obtained: the best ones with a height of technological protrusions of 5 mm and a step between them of 30 mm, the lowest indicator is, respectively, 2.5 mm at any step. Keywords: vibrocentrifuged concrete, physical and mechanical characteristics, compressive strength, density, concrete mix, centrifugation, flexural strength

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MECHANICAL CHARACTERISTICS OF THE MATERIAL OF ADDITIVE STRUCTURES WITH DIFFERENT METHODS FOR DETERMINING THE CROSS-SECTION AREA OF SPECIMENS

Stroitelʹnaâ mehanika i konstrukcii ◽

10.36622/vstu.2021.30.3.006 ◽

2021 ◽

pp. 74-89

Author(s):

А. Ю. Перелыгина ◽

Т. Я. Дружинина ◽

С. А. Антипин ◽

Ю. А. Бобылева

Keyword(s):

3D Printing ◽

Cross Section ◽

Mechanical Characteristics ◽

Sectional Area ◽

Cross Sectional ◽

Cross Section Area ◽

Section Area ◽

Material Homogeneity ◽

Printing Parameters ◽

Central Tension

В статье рассматривается вопрос определения механических характеристик материала аддитивных структур с учетом таких параметров печати, как процент заполнения и направление нитей печати. В исследованиях использовались три типоразмера стандартизированных образцов на центральное растяжение, изготовленных с применением технологии 3D-печати. В ходе экспериментов было установлено, что при определении механических характеристик материала необходимо отходить от гипотезы однородности и сплошности материала, принятой в сопротивлении материалов. Для определения значений механических характеристик у образцов разных типоразмеров была предложена методика по расчету реальной площади поперечного сечения исследуемой структуры. В статье приведены диаграммы растяжения и рассчитанные по ним механические характеристики материала аддитивных структур, а также рассмотрен вопрос влияния отношения площади структуры к площади ограждения на механические характеристики материала. The article discusses the issue of determining the mechanical characteristics of the material of additive structures, taking into account such printing parameters as the percentage of filling and the direction of the printing filaments. The studies used three sizes of standardized specimens for central tension, made using 3D printing technology. During the experiments, it was found that when determining the mechanical characteristics of a material, it is necessary to deviate from the hypothesis of material homogeneity and continuity, adopted in the strength of materials. To determine the values of mechanical characteristics for samples of different sizes, a technique was proposed for calculating the real cross-sectional area of the structure under study. The article presents tensile diagrams and the mechanical characteristics of the material of additive structures calculated from them, as well as the issue of the influence of the ratio of the structure area to the perimeter area on the mechanical characteristics of the material.

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Lessons for New Classes of Inorganic/Organic Composites from the Spicules and Skeleton of the Sea Sponge Euplectella aspergillum

MRS Proceedings ◽

10.1557/proc-844-y4.2 ◽

2004 ◽

Vol 844 ◽

Cited By ~ 3

Author(s):

G. Mayer ◽

R. Trejo ◽

E. Lara-Curzio ◽

M. Rodriguez ◽

K. Tran ◽

...

Keyword(s):

Mechanical Properties ◽

Thin Layer ◽

Cross Section ◽

Mechanical Characteristics ◽

Concentric Ring ◽

Hydrated Silica ◽

Testing Method ◽

Natural Composites ◽

Sponge Spicules

ABSTRACTStudies have been carried out on the structures and mechanical characteristics of an unusual family of sea sponges under the classification of Hexactinellida, genus Euplectella. The sponge spicules have been of interest to materials scientists because of their potentially important optical, coupled with mechanical, properties. The structures of the class Hexactinellida are characterized by a concentric ring appearance in the cross-section, which is a composite of hydrated silica, coupled with silicatein as a thin layer at the ring interfaces. The mechanical behavior and the toughness of the spicules have been examined with the aid of a special fiber testing method, coupled with scanning electrom microscopy (SEM) observations. It appears that there may be common mechanisms underlying toughness in rigid natural composites with high ratios of mineral/organic phase. In addition, novel pressurization tests of a portion of the sponge skeleton have provided information about the resilience of the skeleton, which resembles a selfsupporting glass winding of a cylindrical composite structure.

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