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1

Fatigue damage development in 10CrMo9-10 steel for power plant pipes in as-received state and after 280,000 h of exploitation

Kopec Mateusz, Brodecki Adam, Kowalewski Zbigniew L.

Archives of Civil and Mechanical Engineering

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2023

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Vol. 23, no. 2

art. no. e98, 2023

EN

This paper discusses an effect of 280,000 h of exploitation under internal pressure of 2.9 MPa and high temperature of 540 °C on the mechanical properties of 10CrMo9-10 (10H2M) power engineering steel. The mechanical response of the specimens obtained from two pipes: a new in the as-received state and exploited for a long period was assessed through the uniaxial tensile tests and subsequent fatigue tests. The long-term, high-temperature exposure of 10H2M steel resulted in the deterioration of its mechanical properties and was quantitatively described as a function of the fatigue damage measure, φ, and the fatigue damage parameter D. Finally, the proposed methodology of power exponent approximation with both damage sensitive parameters (φ, D) enabled for successful determination of the 10H2M steel fatigue life.

2

Ultrasonic detection of transversal cracks in rail heads – theoretical approach

Katz Tomasz, Mackiewicz Sławomir, Ranachowski Zbigniew, Kowalewski Zbigniew L., Anatolik Łukasz

Engineering Transactions

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2021

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Vol. 69, iss. 4

437--456

EN

In the paper the calculation of ultrasonic field generated by the transmitting transducer and the pulse-echo amplitude received after beam reflection at the defect in tested material is presented. The focus of the authors is directed on the specific transducer – defect configurations where the common methods of determination of ultrasonic beam trajectory fails. The developed analytical model is based on well-established principles of elastodynamic theory and forms the basis for computer program for simulation of ultrasonic examination of railway rails.

3

Method of reconstructing dynamic load characteristics for durability test Indexed by: of heavy semitrailer under different road conditions

Czarnuch Arkadiusz, Stembalski Marek, Szydłowski Tomasz, Batory Damian

Eksploatacja i Niezawodność

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2021

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Vol. 23, no. 3

548--558

EN

The aim of the article is to present and validate a methodology for collecting road load data on a vehicle, driving on roads and analysis of a drive data signal under the wheel in the time domain, using FRF (Frequency Response Function) and the MTS 320 eight-poster inertia reacted road simulator. The elaborated drive data, was used to control the actuators forcing the movements of the wheels and the coupling part of the semi-trailer during durability tests. The road tests were carried out by registering physical variables in the time domain, by a set of sensors mounted on a vehicle. The data was collected from roads categorized as motorways, national and local roads. Differences between the variability of the parameters, collected on the roads and the variability of the drive data under the wheel, were determined for the particular types of roads, for loaded and unloaded vehicle. The obtained accuracy of reconstruction of the road load data conditions was as high as 97%. Therefore, the proposed method is suitable for reliable durability tests with use of the road simulator.

4

The strength problems in the operation of drum hoist cages

Wolny Stanisław, Matachowski Filip, Drzewosz Agata

New Trends in Production Engineering

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2019

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Vol. 2, Iss. 1

441--449

EN

From information obtained from periodic surveys of cages used in the shaft of one of the Polish mines, it appears that the majority of registered damages of their supporting elements are fatigue cracks. These cracks are formed and develop mainly in main nodes or welds in the areas of their connection with the construction of the cage. In order to eliminate the causes of these damages and to increase the durability of cages, it will probably be necessary to reconstruct those fragments of the cages in which they occur. In order to determine loadings of load-bearing elements and the state of stress that arises in them during the operation of the device, a numerical model of the cage was developed. The results of the calculations made as well as their analysis form the basis for the assessment of the strength and durability of the load-bearing elements of the discussed cage. The key problem determining the durability of the structure – as shown by the analyzes carried out – is the method of constructing the connection of the strings with the appropriate elements of the cage. Changing this state requires significant structural changes of these nodes, which the authors of this study pointed out.

5

Improving the Accuracy of Fatigue Damage Calculations for Archived Data

Leski Andrzej

Fatigue of Aircraft Structures

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2019

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Iss. 11

113--120

EN

Historical operational usage data give a ground for fatigue damage estimation. Quality of sensors and recorders two or more decades ago were lower then modern one. Lack of resolution in nz-level measurement and recording leads to some errors in fatigue damage calculations. In this paper author propose a method to improve the accuracy of fatigue damage calculations for archived data. The method takes advantage of typical distribution of accumulated cycles for aircrafts. Small correction in representative nz value taken in calculations can reduce the error in fatigue damage assessment.

6

Application of X-ray tomography to assess fatigue structural changes in asphalt mixtures

Mackiewicz Piotr, Szydło A.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2019

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Vol. 67, nr 2

307--315

EN

The article presents an analysis of the change in air voids in asphalt mixtures subjected to fatigue tests at three temperatures of 0°C, 10°C and 25°C. The X-ray computerized tomography imaging method, XCT, was used to identify the air voids in the samples. The research allowed to determine changes in the content of air voids in subsequent fatigue cycles in the sample area. The relationship between air voids volume and the stiffness modulus value was also determined during fatigue for three temperatures. The largest changes were found in samples with notches at 0°C. The analysis of the change in the content of air voids showed that the micro-cracking nucleation processes develop with the number of fatigue cycles. Using the numerical model finite element method we determined the distribution and change in fatigue damage in the extreme areas of the sample during various stages of fatigue. We found clear relationship between the damage and the increased content of air voids.

7

Simplified estimate of fatigue damage based on dynamic analysis

Dekys V., Kriska P, Lietava L., Kopas P., Stalmach O.

Zeszyty Naukowe. Transport / Politechnika Śląska

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2018

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z. 99

15--23

EN

The article presents a procedure for vibration analysis of the device based on measured data in simulated operating modes. Subsequently, the criterion of fatigue damage is formulated because this mechanism can be induced or accelerated by recognized operating deflection shapes. The criterion is used to select an optimal set of control device parameter values, which control each device’s operating modes and transitions between these modes and affect the excitation of the frame vibration due to possible shocks in the system. The criterion is formulated based on the vibration displacement processing from these dynamic measurements, the modified Goodman and Palmgren-Miner rules, and the results of static computational analyse. This criterion compares the effect of damage to the modes that control these sets of parameters, while the selection of the optimal control set is performed. At the end of the article, the limitations resulting from the simplifications used are described. The application of this procedure is also useful, for example, when further data are obtained by subsequent experimental stress-strain analysis methods and when we want to reduce the number of possible operating modes by which we carry out subsequent measurements among the most damaging modes.

8

Effective algorithm for structural optimization subjected to fatigue damage and random excitation

Sága M., Vaško M., Ságová Z., Handrik M.

Zeszyty Naukowe. Transport / Politechnika Śląska

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2018

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z. 99

149--161

EN

The aim of the paper is to present the computationally timeconsuming task of simulating the process of randomly oscillating thin-shell structures to realize an optimal design with limitations in terms of fatigue damage. The most important aim here is to design an effective optimization algorithm and choose an appropriate approach for the evaluation of multiaxial fatigue damage in the context of the random and non-proportional character of stress in the structure when considering the standard finite element model. The authors propose their own optimization algorithm, which is described in the present study and, on the basis of tests, has proven to be suitable for the aforementioned technical problems. The proposition of algorithms for calculating the accumulation of fatigue damage in non-proportional and multiaxial stresses (especially in terms of the application of rainflow analysis by decomposition of the equivalent stress, as determined by the appropriate “fatigue” criterion) is very important in such computational processes. The entire computational process was implemented in MATLAB with the “Discret_Opt_Fat” main control program. The article presents the theoretical basis for the presented complex problem solution, its algorithmization and the technical application.

9

Kumulacja uszkodzeń zmęczeniowych stopu aluminium 6082-T6 w warunkach blokowego skręcania

Böhm E., Kurek M., Łagoda T.

Transport Przemysłowy i Maszyny Robocze

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2017

|

Nr 4

58--61

PL

Pęknięcia zmęczeniowe elementów maszyn i urządzeń pod wpływem obciążeń eksploatacyjnych zachodzą najczęściej w warunkach losowych lub zmienno amplitudowych obciążeń. W literaturze występuje bardzo duża liczba opracowanych modeli hipotez zmęczeniowych, zarówno w ujęciu naprężeniowym, odkształceniowym, jak i energetycznym. Najszersze zastosowanie oraz zakres weryfikacji mają hipotezy liniowe o stosunkowo prostym zapisie, pozwalającym na ich pewne modyfikacje.

EN

The paper presents results of experimental research of aluminum alloy 6082-T6 (PA4) under block-type loads. Fatigue testing was performed on the MZGS-100 stand under blocks torsion. The main aim of this paper is present and compare damage accumulation calculations using the hypothesis Palmgrena-Minera and authors model. A new model is based on material memory.

10

Evaluation of fatigue life calculation algorithm of the multiaxial stress-based concept applied to S355 steel under bending and torsion

Macek W., Mucha N.

Mechanics and Mechanical Engineering

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2017

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Vol. 21, nr 4

935--951

EN

This paper presents the results of a study into the stress-based fatigue life calculation algorithm applied to cyclic and random multiaxial proportional and non-proportional loading. This method for high-cycle fatigue, covers both infinite and finite life region, and is based on a critical plane approach combined with rain flow cycle counting and linear damage accumulation. Algorithm based on the method for equivalent scaling of the normal stress in material planes in dependence on the stress state, proposed by Gaier and Danbauer. For analysis the calculated fatigue lives are compared to the experimental results for steel S355 under proportional and non-proportional bending with torsion.

11

Derived equations for damage accumulation in geared wheels based on modified laws of crack propagation

Drewniak J., Rysiński J.

Zeszyty Naukowe. Transport / Politechnika Śląska

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2016

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z. 91

19--31

EN

Versatile hypotheses of fatigue damage accumulation are utilized in order to determine the fatigue life of particular mechanical elements. Such an approach to an analysis of fatigue processes is recognized as being phenomenological. In the present paper, modifications to the Paris and Foreman laws of fracture mechanics have been proposed. The goal of these modifications is an explicit formulation of crack propagation velocity as a function of crack length. Additionally, the process of crack growth was simulated according to the Palmgren-Miner and Pugno-Ciavarella-Cornetti-Carpinteri fatigue hypotheses. The results of simulation were verified based upon test stand experiments.

12

Kumulacja uszkodzeń zmęczeniowych stopu aluminium 6082-T6 w warunkach blokowego zginania

Böhm E., Mytnik M., Kurek M., Łagoda T.

Transport Przemysłowy i Maszyny Robocze

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2016

|

Nr 3

97--100

PL

Wiele elementów konstrukcji, części maszyn poddanych jest obciążeniom o różnych wartościach oraz różnym czasie ich działania. Za zjawisko zmęczenia elementów konstrukcyjnych odpowiedzialne są: rodzaj obciążenia oraz czas jego trwania. Niestety czasami nie można (jednoznacznie odzwierciedlić przebiegu obciążenia elementu podczas próby oszacowania trwałości eksploatacyjnej. Dlatego w czasie badań eksperymentalnych sprowadza się złożony stan obciążenia do bardziej prostego wymiaru, który można odtworzyć w warunkach laboratoryjnych. Najpowszechniej przeprowadza się badania o charakterze okresowo sinusoidalnie zmiennym przebiegu dla rozciągania – ściskania skręcania. Do dziś jednak wielu naukowców próbuje jednoznacznie poznać i określić zjawisko zmęczenia materiałów konstrukcyjnych. Koniunktura dzisiejszego rozwijającego się świata wymusza na konstruktorach, aby już podczas projektowania oszacowali trwałość zmęczeniową elementów.

EN

The paper presents results of experimental research of aluminum alloy 6082-T6 (PA4) under block-type loads. Fatigue testing was performed on the MZGS-100 stand under blocks bending. The main aim of this paper is present and compare damage accumulation calculations using the hypothesis Palmgrena-Minera and authors model. A new model is based on material memory.

13

Fatigue damage of V-lock chain ring under random load

Zhang Q., Wang H., Guo T.

Polish Maritime Research

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2016

|

S 1

4--9

EN

To study the influence of the random load on the V-lock chain ring for mining, the numerical simulation technology is used. The dynamic tension is obtained by using the dynamic model of the plough. The life and damage nephograms are obtained by using ANSYS Workbench. The analysis results show that the short fatigue life region of the V-lock chain ring for mining is mainly concentrated on the transition region between the medial straight edge and arc, and the fatigue damage of the link chain on the side of the motion direction of the plow head is larger than that on the other side. This link chain has strong anti-fatigue performance.

14

Autonomous online system for evaluating steel structure durability

Mantič M., Kuľka J., Faltinová E., Kopas M.

Diagnostyka

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2016

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Vol. 17, No. 3

15--20

EN

The article deals with the design of equipment and its application possibilities for on-line monitoring of operational stress traverse mechanisms. By processing of load spectra it is possible to predict the remaining life in the selected areas of the construction.

15

Fatigue damage detection in composite plate with a circular hole by elastic wave propagation method

Stawiarski A., Miarka S., Barski M., Romanowicz P.

Composites Theory and Practice

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2016

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R. 16, nr 1

20--24

EN

In this study, the elastic wave propagation phenomenon was used to detect the initiation of fatigue damage in a composite plate with a circular hole. The Structural Health Monitoring (SHM) system based on the active pitch-catch measurement technique was proposed. Two configurations of measuring points location were taken into account. The signals from the intact structure were compared with the dynamic response from a structure having a relatively small, interlaminar defect. The influence of the measuring points (actuators and sensors) location on the effectiveness of the damage detection method was performed to obtain an efficient system which can detect the initiation of fatigue damage in a composite plate with a circular hole.

PL

W pracy wykorzystano metodę propagacji fal sprężystych do wykrywania inicjacji uszkodzeń zmęczeniowych w kompozytowej płycie z otworem. Zaproponowano system SHM (Structural Health Monitoring) oparty na aktywnej, transmisyjno-odbiorczej technice pomiarowej. Uwzględniono dwie konfiguracje rozmieszczenia punktów pomiarowych. Sygnały pochodzące ze struktury wzorcowej porównano z dynamiczną odpowiedzią płyty zawierającej stosunkowo niewielki, międzywarstwowy defekt. Określono wpływ lokalizacji punktów pomiarowych (aktywatorów i sensorów) na skuteczność metody detekcji w celu uzyskania efektywnego systemu umożliwiającego wykrycie inicjacji uszkodzenia zmęczeniowego w kompozytowej płycie z otworem.

16

Kumulacja uszkodzeń zmęczeniowych dla obciążeń blokowych z wykorzystaniem pamięci materiału

Böhm E.

Zeszyty Naukowe. Mechanika / Politechnika Opolska

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2015

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z. 105

21-22

EN

The paper presents a new model to calculate the degree of fatigue damage. It is based on the memory of the material. The model is verified on the basis of the block loads (High-Low, Low-High).

17

Modelowanie wpływu niesymetrycznych dwu-blokowych obciążeń na kumulację uszkodzeń zmęczeniowych w stali EN295

Gołoś K., Gołoś A.

TTS Technika Transportu Szynowego

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2015

|

R. 22, nr 12

568--571, CD

PL

W artykule przedstawiono wyniki badań doświadczalnych kumulacji uszkodzeń zmęczeniowych przy cyklicznych dwu-blokowych sekwencjach obciążenia dla cykli symetrycznych i z dodatnim odkształceniem średnim cyklu dla stali En 295. Do analizy danych doświadczalnych oprócz liniowej hipotezy Palmgrena-Minera została wykorzystana również hipoteza Gołosia-Ellyina. Porównanie wyników doświadczalnych i analitycznych wykazało dość dobrą zgodność.

EN

The results of experimental studies of fatigue damage accumulation at the cyclic two-block sequence loading for steel En295 have been presented Studies have shown load sequence effect on fatigue damage accumulation process for the test steel. In the descending load values in a block (H-L) summed linearly measure of accumulation was in the range of 0, 65 to 0.94. If the reverse order of blocks (L-H) linearly summed measure of the accumulation ranged from 1.02 to 1.25. Positive mean strain generally decreases the fatigue life. For the analysis of experimental data in addition to the linear hypothesis Palmgren-Miner has been used a hypothesis put forward by Golos and Ellyin. Predictions based on the analyzed hypothesis for the analyzed test load sequence for symmetrical and with mean strain cycles for steel specimen En295 compared with the data obtained showed good agreement.

18

Effects of various factors on the viv-induced fatigue damage in the cable of submerged floating tunnel

Luo G., Chen J., Zhou X.

Polish Maritime Research

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2015

|

nr 4

76--83

EN

According to the modal superposition method, the vortex vibration procedure of submerged floating tunnel cable was compiled using Matlab, based on the calculated results, the fatigue damage was predicted. The effects of various factors, such as cable density, cable length, and pretension and velocity distribution on vortex induced fatigue damage in the cable were studied. The results show that velocity distribution has more effect on the cable fatigue damage than cable length, cable density and pretension. Secondly, cable length has also relatively effect on the cable damage fatigue, cable density and pretension has limited in a certain range.

19

Obliczanie trwałości zmęczeniowej elementów maszyn na przykładzie wałka obciążonego zginaniem ze skręcaniem

Niesłony A., Owsiński R.

Zeszyty Naukowe. Mechanika / Politechnika Opolska

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2014

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z. 103

141--142

EN

This paper presents an algorithm determining the fatigue life based on a sample of geometry similar to a wheel spindle in a ground vehicles. The calculation has been used MATLAB and FEMAP software. In addition, developed a script that exports the required data from the FEMAP for calculations carried out in MATLAB. Simulation results obtained are consistent with the experimental data.

PL

W niniejszym artykule została zaprezentowana i wykorzystana uproszczona procedura do symulacyjnego wyznaczania trwałości zmęczeniowej próbki z karbem obciążonej kombinacją zginania ze skręcaniem. Uzyskane wartości wieloosiowej analizy zmęczeniowej są zbieżne z danymi eksperymentalnymi. Analizy tego typu mogą być wykorzystane w procesie konstruowania elementów maszyn przed wykonaniem prototypu i testami zmęczeniowymi.

20

Kumulacja uszkodzeń zmęczeniowych z wykorzystaniem pamięci materiału

Böhm E., Kurek M., Junak G., Cieśla M., Łagoda T.

Zeszyty Naukowe. Mechanika / Politechnika Opolska

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2014

|

z. 103

37--38

EN

The paper proposes a new model of fatigue damage accumulation based on the memory of the material and developed on the basis of memorizing of the meaningless material. The comparison of damage accumulation between the classical and proposed model for steel P91 and P92 are in favor of the authors model.

PL

W pracy zaproponowano nowy model kumulacji uszkodzeń zmęczeniowych oparty na pamięci opracowany na podstawie zapamiętywania materiału bezsensownego [1]. Kumulacja uszkodzeń zmęczeniowych (D) oparta jest na wykorzystaniu historii czasowej przebiegu i kumulacji uszkodzeń zmęczeniowych z wykorzystaniem współczynnika zależnego od pamięci materiału.