Search
Search results for: STRESS ANALYSIS
-
Local buckling of compressed flange of cold-formed channel members made of aluminum alloy
PublicationThe paper deals with local buckling of a compressed single flange of thin-walled channel cold- formed columns and beams made of aluminum alloy. Material is described by means of the Ramberg-Osgood constitutive equation. Axial compression of the columns and beams undergoing bending is taken into consid- eration. A simple model of the member flange in the form a long beam elastically connected to the web is used to find the critical...
-
A Diagnostic Method Based on Deflection Analysis for Monitoring Post-elastic Response of Beams
PublicationA non-destructive diagnostic method based on deflection analysis for monitoring the post-elastic response of beams was developed, and a diagnostic indicator was proposed. The indicator was defined as the second moment of the normalised curvature function about the mid-span, where the curvature was computed from the normalised deflection function. Elastic reference values of the indicator were computed for simply supported beams...
-
Application of Barkhausen effect in the impact assessment of welding to internal stress distribution in steel
PublicationThe paper presents identification method of internal stresses in plane steel elements in the chase of deliverance and welding assembly. The assessment was made by means of a non-destructive experimental method based on measurements incorporating local external magnetic field and the measurement of induced voltage, including Barkhausen noise. This method allows a degradation assessment due to internal and external actions, causing...
-
Application of Barkhausen effect in the impact assessment of welding to internal stress distribution in steel
PublicationThe paper presents identification method of internal stresses in plane steel elements in the chase of deliverance and welding assembly. The assessment was made by means of a non-destructive experimental method based on measurements incorporating local external magnetic field and the measurement of induced voltage, including Barkhausen noise. This method allows a degradation assessment due to internal and external actions, causing...
-
Free Vibration of Flexomagnetic Nanostructured Tubes Based on Stress-driven Nonlocal Elasticity
PublicationA framework for the flexomagneticity influence is here considered extending the studies about this aspect on the small scale actuators. The developed model accommodates and composes linear Lagrangian strains, Euler-Bernoulli beam approach as well as an extended case of Hamilton’s principle. The nanostructured tube should subsume and incorporate size effect; however, for the sake of avoiding the staggering costs of experiments,...
-
Estimation of Stresses in a Dry Sand Layer Tested on Shaking Table
PublicationTheoretical analysis of shaking table experiments, simulating earthquake response of a dry sand layer, is presented. The aim of such experiments is to study seismic-induced compaction of soil and resulting settlements. In order to determine the soil compaction, the cyclic stresses and strains should be calculated first. These stresses are caused by the cyclic horizontal acceleration at the base of soil layer, so it is important...
-
Stress anisotropy characterisation with the help of Barkhausen effect detector with adjustable magnetic field direction
PublicationIn the paper we describe a novel apparatus for the measurement of the Barkhausen noise (BN) angular dependence, which in turn may be indicative of the stress induced anisotropy of magnetic properties. Such dependence can be further used for the stress distribution evaluation. The change of magnetization direction in the material is obtained by varying the magnetic flux density in two perpendicular yokes of the apparatus. We present...
-
Optimal reshaping and stress controlling of double-layer spherical structures under vertical loadings
PublicationOptimal reshaping and stress controlling of double-layer spherical structures under vertical loadings
-
STRENGTH of MATERIALS TOWARDS APPLICATIONS (2024)
e-Learning CoursesThe SMTA DATE Course consists of the following problems to be discussed during the lectures: - Introduction to strength of materials towards applications - Fundamentals of modelling in strength of materials towards applications - Materials and basic structures - Fundamentals of modelling in strength of materials towards applications - Definition of environment and loads - General, energy-based and advanced methods for analysis...
-
Process zone in the Single Cantilever Beam under transverse loading. - Part II: Experimental
PublicationThis paper describes an experimental arrangement to evaluate stress/strain fields in the process zone of asymmetric adhesively bonded joints. A transparent polycarbonate flexible beam was bonded to an aluminium alloy rigid block with an epoxy adhesive in a Single Cantilever Beam (SCB) configuration. The flexible adherend was loaded in the direction parallel to the initial crack front at constant rate. To monitor strains induced...
-
A shear stress micromodel of urinary tract infection by the Escherichia coli producing Dr adhesin
PublicationIn this study, we established a dynamic micromodel of urinary tract infection to analyze the impact of UT-segment-specific urinary outflow on the persistence of E. coli colonization. We found that the adherence of Dr+ E. coli to bladder T24 transitional cells and type IV collagen is maximal at lowest shear stress and is reduced by any increase in flow velocity. The analyzed adherence was effective in the whole spectrum of physiological...
-
Historical carpentry corner log joints—Numerical analysis within stochastic framework
PublicationThe paper presents the results of numerical analysis performed on historical, traditional carpentry corner logjoints of two basic topologies: the short-corner dovetail connection and the saddle notch connection. These types of carpentry joints are commonly used in currently preserved objects of wooden architecture. All connections have been modelled in pinewood, which has been defined in the Finite Element software MSC.Marc/Mentat...
-
Stress corossion cracking susceptibility of dissimilar stainless steels welded joints
PublicationW artykule przedstawiono wyniki badań odporności na naprężeniowe pękanie korozyjne złączy różnoimiennych stali odpornych na korozję; austenitycznej 316L oraz typu duplex 2205. Badania próbek przeprowadzono techniką odkształcania z małą prędkością w agresywnym środowisku roztworu chlorku magnezowego. Wyniki badań korozyjnych uzupełniono analizą metalograficzną z obszarów przełomów.
-
Investigations into tendency to stress corrosion of joints welded in austenitic and duplex steels
PublicationPrzedstawiono wyniki badań spawanych złączy różnoimiennych wykonanych ze stali austenitycznej oraz typu duplex 2205. Badania podatności do korozji naprężeniowej złączy wykonano metodą odkształcania z małą prędkością. Próby przeprowadzono w środowisku obojętnym oraz agresywnym (MgCl2).
-
Separation of the effects of notch and macro residual stress on the MFL signal characteristics
PublicationMagnetic flux leakage (MFL) distribution for three configurations of samples has been investigated in order to study the influence of notch and plastic deformation separately as well as together. Samples have been made of S355 steel. The MFL signal measurements were carried out along the longest dimension of the sample over a length of 120 mm. Two components of magnetic field were measured: 1) tangential to the main axis and 2)...
-
FT-Raman spectroscopy as a tool in evaluation the response of plants to drought stress
Publication -
Air Pollution, Oxidative Stress, and the Risk of Development of Type 1 Diabetes
Publication -
Ultrastructural and antioxidative changes in lupine embryo axes in response to salt stress
Publication -
Lupine embryo axes under salinity stress. I. Ultrastructural response
Publication -
Effect of chronic mild stress and imipramine on the proteome of the rat dentate gyrus
Publication -
The Influence of Winter Swimming on Oxidative Stress Indicators in the Blood of Healthy Males
Publication -
Optimal Shape Refurbishment of Distorted Dome Structure with Safeguarding of Member Stress
Publication -
Oxidative Stress Level in the Testes of Mice and Rats during Nickel Intoxication
Publication -
Detection of stress corrosion cracking dynamics by dynamic electrochemical impedance spectroscopy
Publication -
Sweet grass protection against oxidative stress formation in the rat brain
Publication -
Assessment of Life Quality, Stress and Physical Activity Among Patients with Psoriasis
Publication -
Environmental stress cracking in e-glass and aramid/glass epoxy composites
PublicationKompozyty epoksydowe wzmocnione włóknami szklanymi są dość odporne na wpływy środowiskowe w stanie nieobciążonym, jednak po przyłożeniu obciążeń łatwo pękają w środowisku wody i rozcieńczonych kwasów. Charakterystyki propagacji pęknięć środowiskowych w laminatach szklano/epoksydowych były przedmiotem szeregu prac, jednak brak jest danych na temat zachowania laminatów o wzmocnieniu hybrydowym aramidowo-szklanym stosowanych w budowie...
-
Protective effect of desloratadine against oxidative stress in human erythrocytes in vitro
Publication -
Hydroxyproline-Rich Glycoproteins as Markers of Temperature Stress in the Leaves of Brachypodium distachyon
Publication -
The severity of work-related stress and an assessment of the areas of worklife in the service sector
Publication -
Assessment of worklife areas and stress intensity among Border Guard officers
Publication -
Evolution of post welded residual stress due multilayer circumferentialweld of tube.
PublicationOpisano sposób wykorzystania polowego efektu Barkhausena do pomiaru rozkładu naprężeń w spawanych rurach. Przedstawiono procedurę kalibracji oraz wyniki pomiaru naprężeń uzyskanych po stopniowym spawaniu rury.
-
Assessment of fatigue damage of organic coatings subjected to cyclic mechanical stress
PublicationTechnika szumu elektrochemicznego od ponad 20 lat stanowi przedmiot intensywnych badań mających na celu jej praktyczne zastosowanie w monitorowaniu korozji. U podstaw omawianej metody leży odpowiednia analiza rejestrowanych symultanicznie przebiegów prądowych i potencjałowych. W zależności od użytej techniki obróbki danych uzyskane mogą być informacje dotyczące ilościowych (szybkość) i jakościowych (rodzaj zaatakowania) cech procesu...
-
Detection of stress corrosion cracking dynamics by dynamic electrochemical impedance spectroscopy.
PublicationKlasyczne badania korozji naprężeniowej nie dają precyzyjnych informacji o dynamice takiego procesu korozyjnego. Nowa technika dynamicznej elektrochemicznej spektroskopii impedanyjnej, która została opracowana w Katedrze Elektrochemii, Korozji i Inżynierii Materiałowej stwarza takie możliwości. Fakt ten związany z zastosowaną metodologią analizy umożliwiającą selektywną analizą czasowo-częstotliwościową danych pomiarowych.Praca...
-
Direct shear stress vs strain relation for fiber reinforced composites
PublicationThe majority of fiber reinforced composites exhibit strong non-linear behavior in in-plane shear state. The effect is attributed to the micro-cracks appearing in the matrix and can be modeled on the micro and macro level. In this work the author proposes constitutive laws describing the non-linear in-plane shear response, which can be alternative for the relations commonly considered in the literature. The proposed equations are...
-
Hydrogen-enhanced stress corrosion cracking in low alloy steels in seawater
PublicationBadano podatność stali niskostopowych w wodzie morskiej w warunkach polaryzacji katodowej. Stwierdzono spadek czasu do zniszczenia, energii zniszczenia i przewężenia ze wzrostem potencjału katodowego. Wykazano znaczącą korelację między stopniem degradacji wodorowej a stężeniem wodoru dyfuzyjnego.
-
The application of dynamic electrochemical impedance spectroscopy for stress corrosion cracking studies
PublicationElektrochemiczna Spektroskopia Impedancyjna (ESI) od wielu lat stanowi jedno z najważniejszych narzędzi wykorzystywanych do badania różnych procesów elektrochemicznych. Możliwość przeprowadzania badań w łącznej dziedzinie czasowo-częstotliwościowej ułatwia analizę pomiarów impedancyjnych w czasie. ESI pozwala również na analizę mechanizmu procesów elektrochemicznych w dziedzinie czasu z uwzględnieniem bardzo szybkich zjawisk, takich...
-
Analysis of EN 1993-1-6 guidelines about determining amplitudes of equivalent imperfections of steel cylindrical shells subjected to uniform external pressure
PublicationCivil engineering structures should be designed with reference to relevant standards. One of them is a Eurocode 3 standard EN 1993-1-6:2007: Design of steel structures Part 1-6: Strength and Stability of Shell Structures. According to this standard, the value of buckling load can be determined using different approaches: classical hand calculations (stress design) and geometrical and material non-linear analysis of an imperfect...
-
Discussion of Derivability of Local Residual Stress Level from Magnetic Stray Field Measurement
PublicationThe NDT procedure dubbed ‘metal magnetic memory’ method and the related ISO 24497 standard has found wide industrial acceptance in some countries, mainly in Russia and China. The method has been claimed by some researchers (Roskosz and Bieniek in NDT&E Int 45:55–62, 2012; Wilson et al. in Sens Actuators A 135:381–387, 2007) as having potential for quantitative determination of local residual stress state in engineering structures,...
-
The correlation of fractal dimension to fracture surface slope for fatigue crack initiation analysis under bending-torsion loading in high-strength steels
PublicationIn this study, the fractal dimension of fatigue fracture surfaces is investigated in order to find an alternative failure loading indicator. Some of many metrological factors are generalized by reducing the fracture surface structure to one factor and develop an entire fracture surface procedure by analyzing the impact of surface slope and calculation resolution. Three notched geometries are studied under cyclic bending-torsion:...
-
Impact of Brake Wear Particles on Eukaryotic Cell Viability and Associated Oxidative Stress Responses
PublicationIn this study, the cytotoxic effects of brake wear particles (≥250 nm ceramic/ceramic wear particles (CCWPs) and ≤100 nm ceramic/steel wear particles (CSWPs)) and 100 nm iron (III) oxide ultrafine particles (IOUFPs) on human lung carcinoma (A549) and Chinese hamster ovary (CHO) cells were investigated. Cell viability was determined using the MTT and Calcein AM methods. Oxidative stress was assessed by measuring reactive oxygen...
-
Detection of Lexical Stress Errors in Non-Native (L2) English with Data Augmentation and Attention
PublicationThis paper describes two novel complementary techniques that improve the detection of lexical stress errors in non-native (L2) English speech: attention-based feature extraction and data augmentation based on Neural Text-To-Speech (TTS). In a classical approach, audio features are usually extracted from fixed regions of speech such as the syllable nucleus. We propose an attention-based deep learning model that automatically de...
-
Reliability estimation of underground horizontal fuel tank limit states
PublicationFuel tanks are designed with regard to standard loads and operating conditions. The investigations of the paper show the impact of such factors as tank corrosion and other means on the variation of stress fields and deformation of the underground horizontal tank shell. The introduction of probabilistic methods allows for structural reliability assessment. While the computational time of the entire tank FEM model is high, the preliminary...
-
Thermo-resonance analysis of an excited graphene sheet using a new approach
PublicationForced vibration of graphene nanoplate based on a refined plate theory in conjunction with higher-order nonlocal strain gradient theory in the thermal environment has been investigated. Regarding the higher-order nonlocal strain gradient theory, both stress nonlocality and size-dependent effects are taken into account, so the equilibrium equations which are governing on the graphene sheet have been formulated by the theory....
-
Stability analysis of nanobeams in hygrothermal environment based on a nonlocal strain gradient Timoshenko beam model under nonlinear thermal field
PublicationThis article is dedicated to analyzing the buckling behavior of nanobeam subjected to hygrothermal environments based on the principle of the Timoshenko beam theory. The hygroscopic environment has been considered as a linear stress field model, while the thermal environment is assumed to be a nonlinear stress field based on the Murnaghan model. The size-dependent effect of the nanobeam is captured by the nonlocal strain gradient...
-
NON-LINEAR MASTIC CHARACTERISTICS BASED ON THE MODIFIED MSCR (MULTIPLE STRESS CREEP RECOVERY) TEST
PublicationMastic containing asphalt in its composition is an example of a viscoelastic material. It is an effective binder in asphalt. It consists of a filler (<0.063 mm) and asphalt mixed in the right proportions. Just like in asphalt, its response depends on the temperature level, the load and stress time. Changing the stress stiffness of the mastic affects the non-linear course of the stress-strain relationship. Modelling of the non-linear...
-
Galerkin formulations of isogeometric shell analysis: Alleviating locking with Greville quadratures and higher-order elements
PublicationWe propose new quadrature schemes that asymptotically require only four in-plane points for Reissner–Mindlin shell elements and nine in-plane points for Kirchhoff–Love shell elements in B-spline and NURBS-based isogeometric shell analysis, independent of the polynomial degree p of the elements. The quadrature points are Greville abscissae associated with pth-order B-spline basis functions whose continuities depend on the specific...
-
Robust four-node elements based on Hu–Washizu principle for nonlinear analysis of Cosserat shells
PublicationMixed 4-node shell elements with the drilling rotation and Cosserat-type strain measures based onthe three-field Hu–Washizu principle are proposed. In the formulation, apart from displacement and rotationfields, both strain and stress resultant fields are treated as independent. The elements are derived in the frame-work of a general nonlinear 6-parameter shell theory dedicated to the analysis of multifold irregular shells.The...
-
Determinants of Business Growth Aspirations among Polish Students: An Empirical Analysis
PublicationThis paper aims to discuss the concept of growth aspirations and growth intentions, as well as to identify factors that influence growth aspirations expressed by students with regard to their future businesses. On the basis of a literature review potential determinants of growth aspirations have been identified and tested empirically using data obtained from 223 students from the Pomeranian region in Poland. The authors...
-
Stress–strain model of lower corroded steel plates of normal strength for fitness-for-purpose analyses
PublicationThis study investigates the mechanical properties of specimens made of normal strength steel subjected to lower marine immersed corrosion degradation levels (below 25 %). The specimens were corroded in laboratory conditions, and only natural factors were controlled to raise the corrosion rate (reaching the level of 1 mm/year). Three different thicknesses of plates made of normal strength of shipbuilding steel are investigated (between...