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  1. 7 Journal of Theoretical and Applied Mechanics
  2. 4 Inżynieria i Budownictwo
  3. 3 Engineering Transactions
  4. 3 Vibrations in Physical Systems
  5. 2 Archives of Civil Engineering
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  1. 7 Ataman M.
  2. 5 Szcześniak W.
  3. 2 Bajer C.
  4. 2 Bernyś K.
  5. 2 Machelski C.
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  1. 2 2023
  2. 1 2022
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  5. 3 2019
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1
Content available Dynamic analysis of a steel-concrete railway bridges of Langer type under the influence of a moving load
Szaniec Waldemar, Radoń Urszula, Bekő Adrián
Structure and Environment
|
2023
|
Vol. 15, no. 3
147--158
EN
The studying the dynamic response of steel-concrete railway bridges of Langer type is huge importance of ensuring the safety of such structures under high-speed train loads. Numerical simulations at the design stage require knowledge of the modal characteristics: natural frequencies, shapes and damping. In addition, in the dynamics of railway bridges subjected to high-speed trains, it is important to check the impact of dynamic effects on the ultimate and serviceability limit states. As part of the investigations displacements and accelerations of selected measurement points arising from driving the test rolling stock are analyzed. In the first stage, calculations of the eigenvalues and the corresponding eigenvectors were carried out in the Robot program for two variants of mass description (distributed and discrete). In the second stage, dynamic train passages for various vehicle speeds were examined in terms of displacements and accelerations of measurement points by using the authors’ program MES3D.
PL
Badanie odpowiedzi dynamicznej stalowo-betonowych mostów kolejowych typu Langera ma ogromne znaczenie dla zapewnienia bezpieczeństwa takich obiektów pod obciążeniem pociągów dużych prędkości. Symulacje numeryczne na etapie projektowania wymagają znajomości charakterystyk modalnych: częstotliwości drgań własnych, form i tłumienia. Dodatkowo w dynamice mostów kolejowych poddanych działaniu pociągów szybkobieżnych istotne jest sprawdzenie wpływu efektów dynamicznych na stany graniczne nośności i użytkowalności. W ramach badań analizowano przemieszczenia i przyspieszenia wybranych punktów pomiarowych powstałych od jazdy taborem próbnym. W pierwszym etapie przeprowadzono obliczenia wartości własnych i odpowiadających im wektorów własnych w programie Robot dla dwóch wariantów opisu masy (rozłożonej i dyskretnej). W drugim etapie zbadano przebiegi dynamiczne dla różnych prędkości pociągów pod kątem przemieszczeń i przyspieszeń punktów pomiarowych za pomocą autorskiego programu MES3D.
2
Content available Vibrations of an orthotropic plate with point supports subjected to a moving force
Zakęś Filip
Engineering Transactions
|
2023
|
Vol. 71, iss. 3
307--328
EN
We investigate the dynamic behavior of a rectangular orthotropic plate loaded with the concentrated force moving with constant speed along the structure. In this work, we consider two types of plates in terms of boundary conditions. In the first case, we assume that the plate is simply supported on all of its edges with a number of point supports arbitrarily located in its area, and in the second one, we look at a two-span bridge plate with arbitrarily oriented intermediate linear support. Solutions for both cases are obtained by replacing the original structure with a single-span plate subjected to a given moving load and redundant forces situated in positions of removed intermediate supports. Redundant forces are obtained by the application of Volterra integral equations for the simply supported plate, and finite difference discretization and the Newmark method for the bridge plate. Two numerical examples are given to prove the effectiveness of the presented approach.
3
Content available Displacements of shell in soil-steel bridge subjected to moving load: determination using strain gauge measurements and numerical simulation
Machelski Czesław, Sobótka Maciej, Grosel Szczepan
Studia Geotechnica et Mechanica
|
2022
|
Vol. 44, nr 1
26--37
EN
This paper analyses displacements of a shell in a soil-steel bridge subjected to quasi-static moving loads. The considerations relate to a large span structure located in Ostróda, Poland. In particular, shell displacements during a loading cycle consisting of consecutive passages of a pair of trucks over the bridge are investigated. The results of a full-scale test, that is, the readings from a system of strain gauges arranged along the shell circumferential section, are the basis for determination of shell displacements. The proposed algorithm makes it possible to calculate any component of the displacement using just a simple model of the shell in the form of a linear elastic curvilinear beam. The approach uses real measurements, and thus, it yields results of displacements reflecting the actual mechanical behaviour of the entire composite structure including not only the shell, but also the backfill, the pavement, etc. The calculated state of displacement sets the basis for calibration of the numerical model. Finite element (FE) analyses include staged construction, that is, backfilling the shell by placing successive soil layers, as well as the loading test with the vehicles moving over the bridge. It is demonstrated that the ballasting of the shell during backfilling contributes to the improvement of the simulated behaviour of the object at the stage of operation, that is, when subjected to moving truck load. Thus, the calibration of the FE model is successfully carried out using the results of strain gauge measurements.
4
Content available Near-resonant regimes of a moving load on a pre-stressed incompressible elastic half-space
Kudaibergenov Askar, Kudaibergenov Askat, Prikazchikov Danila
Acta Mechanica et Automatica
|
2021
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Vol. 15, no. 1
30--36
EN
The article is concerned with the analysis of the problem for a concentrated line load moving at a constant speed along the surface of a pre-stressed, incompressible, isotropic elastic half-space, within the framework of the plane-strain assumption. The focus is on the near-critical regimes, when the speed of the load is close to that of the surface wave. Both steady-state and transient regimes are considered. Implementation of the hyperbolic–elliptic asymptotic formulation for the surface wave field allows explicit approximate solution for displacement components expressed in terms of the elementary functions, highlighting the resonant nature of the surface wave. Numerical illustrations of the solutions are presented for several material models.
5
Content available remote Nonlinear coupled moving-load excited dynamics of beam-mass structures
Ghayesh M. H., Farokhi H., Zhang Y., Gholipour A.
Archives of Civil and Mechanical Engineering
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2020
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Vol. 20, no. 2
207--217
EN
Investigated in this paper is the first on the moving-load-caused nonlinear coupled dynamics of beam-mass systems. A constant value load excites the beam-mass system where its position on the beam-mass system changes periodically. The energy contribution of the moving load is included via a virtual work formulation. The kinetic energy of the mass together with the beam as well as energy stored in the beam after deflection is formulated. Hamilton’s principle gives nonlinear equations of the beam-mass system under a moving load in a coupled transverse/longitudinal form. A weighted-residual-based discretisation gives a 20 degree of freedom which is numerically integrated via continuation/time integration along with Floquet theory techniques. The resonance dynamics in time, frequency, and spatial domains is investigated. As we shall see, torus bifurcations are present for some beam-mass structure parameters as well as travelling waves. A finite element analysis is performed for a simpler linear version of the problem for to-some-extend verifications.
6
Content available Forced vibrations of a thermoelastic double porous microbeam subjected to a moving load
Kumar Rajneesh, Vohra Richa
Journal of Theoretical and Applied Mechanics
|
2019
|
Vol. 57 nr 1
155--166
EN
The present paper deals with forced vibrations of a homogeneous, isotropic thermoelastic double porous microbeam subjected to moving load, in context of Lord-Shulman theory of thermoelasticity with one relaxation time. The Laplace transform has been applied to obtain expressions for the axial displacement, lateral deflection, volume fraction field and temperature distribution. A numerical inversion technique has been used to recover the resulting quantities in the physical domain. Effects of velocity and time parameters are shown graphically by plotting axial displacement, lateral deflection, volume fraction field and temperature distribution against distance. Some particular cases are also deduced.
7
Content available remote Vibrations of a double-beam system with intermediate elastic restraints due to a moving force
Zakęś Filip, Śniady Paweł
Engineering Transactions
|
2019
|
Vol. 67, iss. 2
243--252
EN
In this paper, we investigate the problem of the dynamic behaviour of a double-beam system with intermediate elastic restraints subjected to a moving point force. Problem is solved by replacing this type of structure with two single-span beams loaded with a given moving force and redundant forces representing reactions in the intermediate restraints. Redundant forces are obtained by solving Volterra integral equations of the second order which are compatibility equations corresponding to each redundant. Solutions for the arbitrarily supported singlespan beam loaded with a moving point force and concentrated time-varying force are given. Difficulties in analytically solving Volterra integral equations are bypassed by applying a simple numerical procedure. Finally, a numerical example of a double-beam system with two elastic restraints is presented in order to show the effectiveness of the presented method.
8
Content available Amplification factors in the case of beam under moving force – theoretical analysis
Ataman M.
Archives of Civil Engineering
|
2019
|
Vol. 65, nr 1
83--96
EN
The impact of a moving load speed on the dynamic overload of beams, assuming that the track of the load has no unevenness, is examined. First the problem of a visco-elastic beam on a Winkler foundation subjected to a force moving at a constant speed will be solved. Using the Bubnov-Galerkin method, the deflections of the beam, and then the bending moments and shear forces will be determined. The solution of the problem will be obtained both for the case of a forced vibration and the case of a free vibration after the moving force has left the beam. Using these solutions, dynamic amplification factors will be determined for the deflections, bending moments, and shear forces, which are different for the two cases. The magnitude of the amplification factors increases and decreases alternately as a function of the speed. In the case of a single force on a beam, the dynamic overloads are limited, and do not exceed 60%. There is no resonance phenomenon in the beam subjected to the single moving force. The dynamic amplification factors determined in this way can be used as correction coefficients when designing engineering structures subjected to moving loads by static methods.
PL
W niniejszej pracy przeanalizowany został wpływ prędkości pojazdów na wielkość współczynników dynamicznych, określonych wzorami (1.3), przy założeniu, że nawierzchnia jest bez nierówności. Wpływ ruchomego obciążenia na drgania nawierzchni drogowej i kolejowej oraz mostów drogowych i kolejowych przedstawiono rozwiązując zadanie belki swobodnie podpartej spoczywającej na podłożu odkształcalnym, obciążonej siłą poruszającą się ze stałą prędkością. Wyznaczono współczynniki dynamiczne, które są różne w przypadku ugięć, momentów zginających i sił poprzecznych (wzory (3.1) – (3.3)). W analizie uwzględniono zarówno drgania wymuszone jak również drgania swobodne, kiedy obciążenie jest już poza belką. Położenie siły opisane jest bezwymiarową współrzędną η=vt/l. Zatem przy η≤1 ruchoma siła znajduje się na przęśle (drgania wymuszone), zaś przy η>1 siła jest już poza belką (drgania swobodne). Przytoczono z monografii [6] wzory uogólniające, określające górne granice współczynników dynamicznych, uzyskane na podstawie obliczeń przeprowadzonych przy różnych wartościach parametru opisującego położenie ruchomej siły vt/l. W przypadku współczynnika dynamicznego maksymalnego ugięcia i momentu zginającego środka pojedynczego przęsła są to odpowiednio wzory (3.4) i (3.5). Z kolei współczynnik dynamiczny siły poprzecznej tuż przy podporze dany jest wzorem (3.6).
9
Content available Przegląd publikacji polskich autorów z zakresu obciążeń ruchomych na konstrukcjach inżynierskich
Szcześniak W., Ataman M.
Autobusy : technika, eksploatacja, systemy transportowe
|
2018
|
R. 19, nr 12
667--674
PL
W artykule omówiono prace dotyczące tematyki obciążeń ruchomych na belkach płytach i powłokach w polskiej literaturze. Omówiono większość opracowań, w których Autorzy analizowali ruchome obciążenia inercyjne oraz bezinercyjne. Przedstawiono prace zawierające rozwiązania analityczne jak również prace, w których do rozwiązania zadania wykorzystano metody komputerowe. Załączony wykaz publikacji z literatury przedmiotu zawiera 202 pozycje.
EN
In the paper survey of Polish literature concerning moving loads is presented. In most of these studies the authors analysed moving inertial loads and moving massless loads. Works presenting analytical solutions as well as works in which computer methods were used to solve the problem were presented. An extensive list of publications on the related literature, attached to the paper contains 202 items.
10
Content available Dynamic response of ladder track rested on stochastic foundation under oscillating moving load
Mohammadzadeh S., Mehrali M.
Journal of Theoretical and Applied Mechanics
|
2017
|
Vol. 55 nr 1
281--291
EN
The ladder track is a new type of an elastically supported vibration-reduction track system that has been applied to several urban railways. This paper is devoted to the investigation of dynamic behavior of a ladder track under an oscillating moving load. The track is represented by an infinite Timoshenko beam supported by a random elastic foundation. In this regard, equations of motion for the ladder track are developed in a moving frame of reference. In continuation, by employing perturbation theory and contour integration, the response of the ladder track is obtained analytically and its results are verified using the stochastic finite element method. Finally, using the verified model, a series of sensitivity analyses are accomplished on effecting parameters including velocity and load frequency.
11
Content available Zastosowanie metody różnic skończonych w dynamice cienkich płyt mostowych poddanych działaniu obciążeń ruchomych
Zakęś F.
Czasopismo Inżynierii Lądowej, Środowiska i Architektury / Journal of Civil Engineering, Environment and Architecture
|
2017
|
z. 64, nr 2/I
7--16
PL
Praca przedstawia rozwiązanie zagadnienia drgań nietłumionych cienkiej prostokątnej płyty mostowej poddanej działaniu obciążenia nieinercyjnego poruszającego się ze stałą prędkością. Zastosowane zostały znane procedury numeryczne Metody Różnic Skończonych, mające na celu dyskretyzację przestrzenną obszaru płyty, a także algorytmy metody Newmarka przy dyskretyzacji czasu przejazdu obciążenia przez płytę. Podano formuły pozwalające zbudować i rozwiązać macierzowe równanie ruchu w tym budowę wektorów obciążeń dla przypadku ruchomej siły skupionej oraz ruchomego obciążenia rozłożonego. Praca uzupełniona jest przykładem numerycznym płyty mostowej podpartej 4 słupami obciążonej dwoma rodzajami obciążenia ruchomego.
EN
This paper presents solution of problem of undamped vibrations of thin rectangular bridge plate subjected to a non-inertial load moving with constant velocity. In order to spatial discretization of the plate numerical procedures have been applied as well as formulas of Newmark method applied to discretize time of the load movement. Formulas required to build and solve matrix equation of motion have been given as well as formulas for load vectors corresponding with two cases of moving load namely the case of moving constant force and the case of moving distributed load. A numerical example of a bridge plate with 4 point supports subjected to 2 types of moving load has been presented in order to show the efficiency of the method.
12
Content available remote Bilevel limit analysis of self-hardening rod systemsunder moving load
Alawdin P., Urbańska K.
Computer Assisted Methods in Engineering and Science
|
2017
|
Vol. 24, no. 4
225--238
EN
This paper considers results of an analysis of self-hardening systems (SHS), i.e. load-carrying systemswith improved strength and rigidity. The indicated structural features can be only found if geometricalnonlinearity is taken into consideration. Material deforming diagrams can be non-monotonic and non-smooth, and constraints can be unilateral, with gaps. Furthermore, optimisation of a mathematical modelof a rod structure as a discrete mechanical system withstanding dead (constant) and/or moving loadsis proposed. This model is formulated using bilevel mathematical programming. The limit parametersof standard loads and actions are found in the low-level optimisation. An extreme energy principle isproposed to obtain the limit parameters of these actions. Onthe upper level, the parameters of movingload are maximized. A positive influence of equilibrium or quasi-equilibrium constant load with the possiblepreloading of SHS is shown. A set of criteria for the stability of plastic yielding of structures, including non-smooth and non-convex problems of optimisation is given. The paper presents an exemplary application of the proposed method which takes into account the self-hardening effect.
13
Content available Use of the finite element method in predicting vibrations of sandwich beams and plates resting on deformable foundations subjected to moving loads
Zbiciak A., Ataman M., Szcześniak W.
Archives of Civil Engineering
|
2017
|
Vol. 63, nr 4
51--69
EN
This paper presents the capabilities of ABAQUS finite-element program [1] in modelling sandwich beams and plates resting on deformable foundations. Specific systems of sandwich beams and plates separated by an elastic core layer were subjected to the action of point and distributed moving loads. A few theoretical examples are provided to present different techniques of modelling the foundations and the moving loads. The effects of the boundary conditions and of the foundation parameters on the deflections of the analysed structures are also presented.
PL
Ograniczeniem zastosowania metod analitycznych do rozwiązania zagadnień dynamicznych belek i płyt pod obciążeniami ruchomymi są przede wszystkim trudności w spełnieniu warunków brzegowych w belkach i płytach. Z tego też powodu w większości przypadków stosuje się metody przybliżone typu MES, MECZ, MEB, DQM oraz metodę różnic skończonych, w których łatwo jest zamodelować dowolne warunki brzegowe. Metody te pozwalają również na uwzględnienie różnorodności materiałów i elementów konstrukcyjnych. W niniejszej pracy przedstawiono możliwości wykorzystania programu metody elementów skończonych (MES) ABAQUS [1] do modelowania belek i płyt warstwowych spoczywających na odkształcalnych podłożach. Układy takie poddano działaniu ruchomych obciążeń, zarówno skupionych jak i rozłożonych. W kilku przykładach pokazano różne techniki modelowania podłoża i ruchomego obciążenia.
14
O wpływach obciążeń ruchomych na przepusty ze stalowych blach falistych
Bęben D.
Inżynieria i Budownictwo
|
2016
|
R. 72, nr 11
590--594
PL
Przedstawiono analizę wpływu obciążenia ruchomego (drogowego i kolejowego) na przepusty z blach falistych. Określono doświadczalnie wpływ obciążenia eksploatacyjnego (drogowego i kolejowego) na tego rodzaju przepusty. Ustalono także współczynniki dynamiczne i zweryfikowano założenie dotyczące nieuwzględniania wpływów dynamicznych na przepusty, w których naziom przekracza 1,0 m.
EN
The paper presents an analysis of the impact of moving load (road and railway) on the corrugated steel plate culverts. The impact of the service loads (road and railway) for this type of culverts has been determined experimentally. It was also established the dynamic amplification factors and the assumption regarding not taking account the dynamic influences on culverts where the soil cover exceeds 1.0 m has been verified.
15
Content available remote Vibrations of point-supported rectangular thin plate subjected to a moving force
Zakęś F.
Engineering Transactions
|
2016
|
Vol. 64, iss. 4
409--415
EN
In this paper, the dynamic behaviour of a rectangular thin plate simply supported on all edges and point supported within its region is investigated. The problem is solved by replacing this type of structure with a simply supported plate subjected to a given moving load and redundant forces situated in positions of intermediate point supports. Redundant forces are obtained by solving Volterra integral equations of the first order, which are compatibility equations corresponding to each redundant. Solutions for a simply supported plate loaded with a moving point force and concentrated time-varying force are given. Difficulties of solving Volterra integral equations analytically are bypassed by applying a simple numerical procedure. Finally, a numerical example of a plate with two point supports is presented in order to show the effectiveness of the presented method.
16
Content available Nonlinear dynamic analysis of a rectangular plate subjected to accelerated/decelerated moving load
Mamandi A., Mohsenzadeh R., Kargarnovin M. H.
Journal of Theoretical and Applied Mechanics
|
2015
|
Vol. 53 nr 1
151--166
EN
In this paper, nonlinear dynamical behavior of a rectangular plate traveled by a moving mass as well as an equivalent concentrated force with non-constant velocity is studied. The nonlinear governing coupled partial differential equations (PDEs) of motion are derived by energy method using Hamilton’s principle based on the large deflection theory in conjuncture with the von-Karman strain-displacement relations. Then Galerkin’s method is used to transform the equations of motion into a set of three coupled nonlinear ordinary differential equations (ODEs) which then is solved in a semi-analytical way to get the dynamical response of the plate. Also, by using the Finite Element Method (FEM) with ANSYS software, the obtained results in nonlinear form are verified by FEM results. Then, a parametric study is conducted by changing the size of moving mass/force and the velocity of the traveling mass/force with a constant acceleration/deceleration, and the outcome nonlinear results are compared to the results from linear solution.
17
Zastępcze obciążenie ruchome mostów kolejowych
Machelski C.
Inżynieria i Budownictwo
|
2015
|
R. 71, nr 9
492--495
PL
Zaproponowano metodykę porównywania obciążeń ruchomych z wykorzystaniem obciążenia zastępczego w postaci siły równomiernie rozłożonej na długości belki jako równoważnego (ekwiwalentnego) do skutków wywoływanych przez złożone układy sił. Takie ujęcie obciążenia zastępczego umożliwia bezpośrednie porównywanieze sobą skuteczności wybranych schematów obciążeń normowych, projektowych, wzorcowych i eksploatacyjnych stosowanych w mostach. Wykorzystywany algorytm pozwala również na obliczanie mnożników obciążenia stosowanych do kwalifikacji obciążeń mostów kolejowych według normy PN-EN 15528.
EN
The methodology implementing movable loads can be useful for the assessment of structural behaviour of shell in soil-steel structures. It enables to determine the number of effective vehicle axle loads acting on the shell. The paper proposes the structural stiffness determined on the basis of shell deflection measured during load testing as the basis for assessing the quality of construction works. The examples prove that this method can be better for the evaluation than the index defined in standards as the span/deflection ratio used in the case of beam bridges.
18
Analiza możliwości wystąpienia rezonansu częstotliwościowego liny nośnej kolei dwulinowej wywołanego obciążeniem ruchomym
Knawa-Hawryszków M.
Inżynieria i Budownictwo
|
2015
|
R. 71, nr 10
560--563
PL
Przeanalizowano wpływ parametrów ruchu potoku pojazdów pasażerskich, stanowiącego obciążenie użytkowe kolei dwulinowej, w aspekcie możliwości wystąpienia zjawiska rezonansu częstotliwościowego liny nośnej, które może mieć istotny wpływ na komfort jazdy, jak też możliwe efekty zmęczeniowe w linie. Analizę numeryczną przeprowadzono w zakresie liniowym, z wykorzystaniem opracowanego ciągłego modelu obliczeniowego.
EN
In this paper an influence of motion parameters of passenger carriers, which constitute an in-service load of bi-cable ropeway system, has been investigated in aspect of possible frequency resonance effect in the track rope. That may be significant taking into account ride comfort of passengers and possible rope fatigue. Numerical analysis has been performed for linear problem, using elaborated continuous calculation model.
19
Content available Topology optimization for elastic base under rectangular plate subjected to moving load
Jilavyan S. H., Khurshudyan A. Zh.
Archives of Control Sciences
|
2015
|
Vol. 25, no. 3
289--305
EN
Distribution optimization of elastic material under elastic isotropic rectangular thin plate subjected to concentrated moving load is investigated in the present paper. The aim of optimization is to damp its vibrations in finite (fixed) time. Accepting Kirchhoff hypothesis with respect to the plate and Winkler hypothesis with respect to the base, the mathematical model of the problem is constructed as two–dimensional bilinear equation, i.e. linear in state and control function. The maximal quantity of the base material is taken as optimality criterion to be minimized. The Fourier distributional transform and the Bubnov–Galerkin procedures are used to reduce the problem to integral equality type constraints. The explicit solution in terms of two–dimensional Heaviside‘s function is obtained, describing piecewise–continuous distribution of the material. The determination of the switching points is reduced to a problem of nonlinear programming. Data from numerical analysis are presented.
20
Content available remote Dynamic responses of a gantry crane system due to a moving body considered as moving oscillator
Zrnić N. D., Gašić V. M., Bošnjak S. M.
Archives of Civil and Mechanical Engineering
|
2015
|
Vol. 15, no. 1
243--250
EN
This paper discusses a combined finite element and analytical method for obtaining transverse and longitudinal vibrations of a gantry crane system subjected to an elastically suspended moving body. The two-dimensional inertial effects of the moving body are included in derivation of differential equation of motion for the system. Factors as speed, acceleration and suspension characteristics of a moving body are studied, including the influence of structural damping. The obtained results validate the presented approach and can be used in the design process of gantry cranes.
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