scholarly journals Mathematical model for determining the limit load capacity of an energy-intensive profile of class 4

2018 ◽  
Vol 19 (9) ◽  
pp. 133-136
Author(s):  
Dominik Gałdyński
Keyword(s):  
Mathematical Model ◽  
Cross Section ◽  
Load Capacity ◽  
Limit Load ◽  
Stress And Strain ◽  
Mathematical Apparatus ◽  
Load Bearing Capacity ◽  
Automotive Body ◽  
The Impact

The article discusses the process of stress and strain changes for an energy-intensive profile with a square cross-section as a result of axial compression, expressed using a mathematical apparatus that allows determination of the load-bearing capacity of such a profile, the use of which in the form of stringers is found in modern automotive body constructions . Elements, such as the so-called a zone of controlled crumpling, taking over part of the impact energy, at the same time being responsible for the progressive nature of the deformation of this area.

scholarly journals The influence of the torsional restraint of crane column brackets on their critical load capacity

2019 ◽  
Vol 262 ◽  
pp. 09009 ◽  
Author(s):  
Michał Redecki ◽  
Bronisław Gosowski
Keyword(s):  
Critical Load ◽  
Cross Section ◽  
Load Distribution ◽  
Load Capacity ◽  
Lower Segment ◽  
Load Bearing Capacity ◽  
Contour Maps ◽  
Axis Of Rotation ◽  
Parametric Studies ◽  
The Impact

The paper presents the results of numerical parametric studies conducted on laterally restrained steel I-columns with a single stepped asymmetric change in their cross-section. Such elements are used as a part of the outermost columns in the transversal system of steel halls with cranes. The columns are usually braced along their length with wall girts, which in a properly structured hall system have a significant effect on the columns’ load bearing capacity and determine their axis of rotation. The main aim of the presented studies is to determine the impact of parameters, such as longitudinal load distribution on the upper and lower segment of the column, the number of pointed lateral bracings and their distance to a column's external flange, and also the application of torsional restraint on the critical load capacity. Results are presented as surfaces or contour maps, in which the ordinates represent the critical loads with regards to the analysed parameters. The paper ends with practical conclusions.

scholarly journals A Control Based Mathematical Model for the Evaluation of Intervention Lines in COVID-19 Epidemic Spread: The Italian Case Study

Symmetry ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 890
Author(s):  
Paolo Di Giamberardino ◽  
Rita Caldarella ◽  
Daniela Iacoviello
Keyword(s):  
Mathematical Model ◽  
Equilibrium Points ◽  
Italian Case ◽  
Control Actions ◽  
Containment Measures ◽  
Asymptomatic Subjects ◽  
The Impact

This paper addresses the problem of describing the spread of COVID-19 by a mathematical model introducing all the possible control actions as prevention (informative campaign, use of masks, social distancing, vaccination) and medication. The model adopted is similar to SEIQR, with the infected patients split into groups of asymptomatic subjects and isolated ones. This distinction is particularly important in the current pandemic, due to the fundamental the role of asymptomatic subjects in the virus diffusion. The influence of the control actions is considered in analysing the model, from the calculus of the equilibrium points to the determination of the reproduction number. This choice is motivated by the fact that the available organised data have been collected since from the end of February 2020, and almost simultaneously containment measures, increasing in typology and effectiveness, have been applied. The characteristics of COVID-19, not fully understood yet, suggest an asymmetric diffusion among countries and among categories of subjects. Referring to the Italian situation, the containment measures, as applied by the population, have been identified, showing their relation with the government's decisions; this allows the study of possible scenarios, comparing the impact of different possible choices.

Theoretic-Strength Concept of a Model Describing the Destruction of the Corner Part of a Slab-Column Structure

2015 ◽  
Vol 240 ◽  
pp. 225-231 ◽  
Author(s):  
Mirosław Wieczorek
Keyword(s):  
Reinforced Concrete ◽  
Cross Section ◽  
Laboratory Tests ◽  
Concrete Slab ◽  
Load Capacity ◽  
Limit Load ◽  
Traditional Theory ◽  
Load Step ◽  
Reinforced Concrete Slab ◽  
Column Structure

The paper presents a proposed theoretical-strength destruction model of the corner of a slab-column structure at 1:2 scale. The theoretical destruction model was developed on the basis of laboratory tests of a reinforced concrete slab with the dimensions 4000×4000×100 mm. The assumptions of the proposed theoretical model were based on a traditional theory of behaviour of reinforced concrete constructions. The method for calculating the strength of reinforced concrete sections is based on interaction graphs of the load capacity NRd, MRd,x and MRd,y. The calculation method takes into account the influence of changes in the shape of the cross-section of the analysed element on its limit load capacity in every load step.

scholarly journals Impact of the cross section library on 93mNb activity in VVER-1000 reactor dosimetry

2020 ◽  
Vol 225 ◽  
pp. 03009
Author(s):  
P. Haroková ◽  
M. Lovecký
Keyword(s):  
Cross Section ◽  
Neutron Transport ◽  
Nuclear Data ◽  
Nuclear Data Library ◽  
The Cross ◽  
Materials Used ◽  
The Impact ◽  
Data Library ◽  
Reactor Dosimetry

One of the objectives of reactor dosimetry is determination of activity of irradiated dosimeters, which are placed on reactor pressure vessel surface, and calculation of neutron flux in their position. The uncertainty of calculation depends mainly on the choice of nuclear data library, especially cross section used for neutron transport and cross section used as the response function for neutron activation. Nowadays, number of libraries already exists and can be still used in some applications. In addition, new nuclear data library was recently released. In this paper, we have investigated the impact of the cross section libraries on activity of niobium, one of the popular materials used as neutron fluence monitor. For this purpose, a MCNP6 model of VVER-1000 was made and we have compared the results between 14 commonly used cross section libraries. A possibility of using IRDFF library in activation calculations was also considered. The results show good agreement between the new libraries, with the exception of the most recent ENDF/B-VIII.0, which should be further validated.

Evaluation of the limit load capacity of a body with crack and determination of the temperature of brittle?Ductile transition in metals

1987 ◽  
Vol 19 (12) ◽  
pp. 1603-1609
Author(s):  
A. Ya. Krasovskii ◽  
V. N. Krasiko ◽  
V. M. Torop ◽  
I. V. Orynyak
Keyword(s):  
Load Capacity ◽  
Limit Load ◽  
Brittle Ductile Transition

Calculation of the blank twist angle at processing with planetary turning

2016 ◽  
Vol 230 (18) ◽  
pp. 3298-3303 ◽  
Author(s):  
Mikhail S Razumov ◽  
Aleksandr N Grechukhin ◽  
Alexey O Gladyshkin
Keyword(s):  
Mathematical Model ◽  
Cross Section ◽  
Cutting Forces ◽  
Twist Angle ◽  
Mathematical Expression ◽  
Research Problem ◽  
Calculation Scheme ◽  
Technological System ◽  
Test Calculation

The work deals with consideration of the technology of forming many-sided outer surfaces with the variable profile of planetary turning. The peculiarities of this technology were detected and the actuality of the research problem was specified. The essence of study lies in the determination of the cutting force’s effect on the blank rigidity. The calculation scheme and mathematical model, which allow studying the cutting forces effect on the rigidity of technological system during processing, were stated. The dependence of blank rigidity on the form of cross section processing with multiple-blade instrument with planetary movement was determined. The mathematical expression of the allowable twist angle under effect of cutting forces on the blank was offered. This study can be applied as the test calculation at projecting of technological rigging and setting modes of cutting at forming of many-sided outer surfaces with variable profile of planetary turning.

The Research on Damage and Failture Mechanism of Drivepipe under Seismic Load

2011 ◽  
Vol 374-377 ◽  
pp. 2096-2099
Author(s):  
Xiang Cao Zhi ◽  
Jia Zhu Xue ◽  
Xiu Li Cao
Keyword(s):  
Mathematical Model ◽  
Mechanical Model ◽  
Strain Analysis ◽  
Seismic Load ◽  
Stress And Strain ◽  
Mechanical Method ◽  
Mechanism Research ◽  
Geological Factors ◽  
Stress Damage ◽  
The Impact

Geological factors and engineering factors is a major factor to damage, the drivepipe deformation under pressure seismic load which used to establish mathematical model of the mechanical model can calculated the stress and strain analysis of the casing. The drivepipe damage to this article on the mechanism research on the mechanical model of drivepipe analysis under Seismic load, based on the drivepipe through the focus on the impact and stress damage to the mechanical method of drivepipe deformation studies, and the models of a drivepipe failure mechanism of the mechanical and mathematical are established, which will scientifically, accurately predict the damaged drivepipe.

scholarly journals IMPLICATIONS OF AN R-SCAN FOR CHARM PHYSICS

2014 ◽  
Vol 35 ◽  
pp. 1460386
Author(s):  
JOHANN H. KÜHN
Keyword(s):  
Cross Section ◽  
Quark Mass ◽  
Charm Physics ◽  
Threshold Region ◽  
High Luminosity ◽  
Electron Positron Annihilation ◽  
Electron Positron ◽  
The Impact ◽  
The Continuum

The impact of improved measurements of the cross section for electron-positron annihilation into hadrons in the charm threshold region is discussed. Two aspects are studied in detail: i.) A significant reduction of the experimental error of the electronic width of the narrow resonances J/ψ and ψ′ and of the continuum cross section from the open charm threshold up to 4.6 GeV will lead to a correspondingly improved determination of the charmed quark mass; ii) A high luminosity measurement with 24 pb-1 at three points and with a spacing of 2 MeV around [Formula: see text] may allow to observe the direct, resonant production of χc1.

scholarly journals Load capacity of the board grillage with two stringers under ice loading

2021 ◽  
pp. 15-21
Author(s):  
А.И. Притыкин
Keyword(s):  
Load Capacity ◽  
Limit Load ◽  
Analytical Relation ◽  
Complex Character ◽  
Ice Load ◽  
Rectangular Area ◽  
Fixed Area ◽  
Numerical Coefficient ◽  
Analytical Relations

Снизить повреждаемость бортовых перекрытий при ледовых нагрузках можно за счет совершенствования расчетных зависимостей по оценке их несущей способности. Далеко не всегда такие зависимости, приводимые в справочных изданиях, дают верные рекомендации из-за не вполне ясного характера распределения нагрузок в сложных статически неопределимых системах. В справочнике по СМК приводится расчетная зависимость, позволяющая определить несущую способность регулярного перекрытия с двумя стрингерами при действиии локально распределенной нагрузки в пределах прямоугольника. Цель данной работы заключалась в оценке несущей способности реального бортового перекрытия ледокола типа Wind с помощью МКЭ при параметрах ледовой нагрузки, определяемой рекомендациями Морского Регистра РФ, и последующем сравнении полученных результатов с расчетами по теоретической зависимости, приведенной в справочнике. Полученные данные показали, что зависимость в справочнике для оценки несущей способности перекрытия дает удовлетворительно согласующиеся с МКЭ результаты после соответствующего уменьшения числового коэффициента в ней. При анализе несущей способности перекрытия варьировались шпация, толщина обшивки, высота стенок стрингеров и площадь приложения нагрузки. Установлено, что текучесть наблюдается в опорных сечениях шпангоутов и посредине их пролета, а из-за большой ширины присоединенного пояска обшивка у контура перекрытия практически никогда не течет. Полученные МКЭ результаты показали наличие обратно пропорциональной зависимости между предельной нагрузкой и шпацией при фиксированной площади нагружения. Отмечено, что увеличение толщины обшивки несущественно влияет на величину предельной нагрузки при остальных неизменных параметрах перекрытия. Выполненные расчеты позволяют кроме предельной нагрузки оценить также и величины прогибов при упругопластическом деформировании перекрытий, которые затруднительно подсчитать аналитически. To low damage of the board grillages under ice loading is possible by improving analytical relations on estimation of their load capacity. Not always such relations, bringing in manuals, give true recommendations because of complex character of the loads distribution in static indeterminate systems. Im manual on ship structural mechanics is giving analytical relation for determination of load capacity of regular grillage with two stringers under action of localy distributed load in rectangular area. Purpose of this study is to estimate load capacity of real board grillage of icebreaker of type Wind with help of FEM under parameters of ice load recommended in Maritime Register of RF, and following comparison of obtained results with calculation on analytical relation, given in manual. Obtained results show that relation in manual for estimation of load capacity of grillage give satisfactory results corresponding to FEM only after corresponding reducing of numerical coefficient in it. Under analysis of load capacity of grillage, it was changing frame space, thickness of plating, depth of stringers and area of application of load. It was estimated that most loaded zones of frames are their sections near supports and in the mid-span. Because of big width of associated plate the plating near contour of grillage is never yielding practically. Results obtained by FEM show existence of inversely proportional relation between the limit load and space framing under fixed area of loading. It was noticed that increasing of the plating thickness influent not essentially on value of the limit load under all other parameters of grillage unchangeable. Performed calculations allow to estimate limit load and value of deflections under elasto-plastic deformation of grillage, which is difficult to calculate analytically,

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