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1

Wielokryterialna ocena wybranych rozwiązań elewacji wentylowanych

Leśniak Agnieszka, Górka Monika

Materiały Budowlane

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2022

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nr 10

21--23

PL

Elewacje wentylowane stanowią alternatywę dla standardowych tynków elewacyjnych. Wykonuje się je z wykorzystaniem różnych płyt okładzinowych i konstrukcji rusztu. W artykule podjęto próbę wskazania najkorzystniejszego rozwiązania elewacji wentylowanej na podstawie przyjętych kryteriów oceny. Poddano analizie trzy warianty elewacji: z płyt aluminiowych przykręcanych do podkonstrukcji aluminiowej wkrętami samowiercącymi; z płyt kompozytowych zawieszanych na podkonstrukcji aluminiowej oraz z płyt włókno-cementowych nitowanych do podkonstrukcji. Do analizy wielokryterialnej wykorzystano metodę PROMETHEE II.

EN

Ventilated facades are an alternative to standard facade panels. It is made with the use of various materials for cladding panels and substructures. In the paper, the authors tried to determine the most advantageous solution for the execution of the ventilated facade on the basis of the 7 recognized evaluation criteria. Three variants of the facade were analysed: aluminium panels screwed to the aluminium substructure with self-drilling screws; composite panels suspended from the aluminium substructure; fibre-cement panels riveted for substructures for the multi-criteria analysis, the PROMETHEE II method was used.

2

Experimental study on demountable steel ultra‑high performance concrete composite slabs under hogging moment

Guo Jun‑Yuan, Wang Jun‑Yan, Wang Yan-Bo, Gao Xiao‑Long, Bian Chen

Archives of Civil and Mechanical Engineering

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2022

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Vol. 22, no. 3

art. no. e137

EN

Demountable steel-concrete composite structures have attracted much attention from researchers because of its fast construction, demountability and environmental friendliness. Using ultra-high performance concrete (UHPC) in the hogging moment regions of demountable steel-concrete composite structures might improve their crack resistance and flexural performance. In this study, the cracking behavior, failure mode, stiffness, ultimate strength and relative slip of demountable steel-UHPC composite slabs with different stud spacings and longitudinal reinforcement ratios under hogging moment were experimentally investigated. A welded steel-UHPC composite slab was also tested to compare its behavior with the demountable slabs. The test results show the demountable steel-UHPC composite slabs have excellent crack control ability under hogging moment due to the slip of threaded headed stud and the strain hardening behavior of UHPC; the relative slip is directly associated with the stud spacing and controlled by the friction and shear force of threaded headed studs. As compared to the welded composite slab, the demountable composite slab can be easily separated after loading, the flexural capacity is slightly smaller, while the crack control ability is better and the ductility is higher. A constitutive model considering the reduction of tensile strength of UHPC after reinforcement was adoptedl the design formulas were developed to predict the elastic limit and the ultimate moment, and the bending stiffness of the demountable composite slabs under hogging moment. The test results verify the applicability of the proposed constitutive model of UHPC and design formulas.

3

Experimental investigation of chopped steel wool fiber at various ratio reinforced cementitious composite panels

Rmdan Amer Akrm A., Al Bakri Abdullah Mohd Mustafa, Ming Liew Yun, Aziz Ikmal Hakem A., Mohd Tahir Muhammad Faheem, Abd Rahim Shayfull Zamree, Amer Hetham A. R.

Archives of Civil Engineering

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2021

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Vol. 67, nr 3

661--671

EN

The flexural toughness of chopped steel wool fiber reinforced cementitious composite panels was investigated. Reinforced cementitious composite panels were produced by mixing of chopped steel wool fiber with a ratio range between 0.5% to 6.0% and 0.5% as a step increment of the total mixture weight, where the cement to sand ratio was 1:1.5 with water to cement ratio of 0.45. The generated reinforced cementitious panels were tested at 28 days in terms of load-carrying capacity, deflection capacities, post-yielding effects, and flexural toughness. The inclusion of chopped steel wool fiber until 4.5% resulted in gradually increasing load-carrying capacity and deflection capacities while, provides various ductility, which would simultaneously the varying of deflection capability in the post-yielding stage. Meanwhile, additional fiber beyond 4.5% resulted in decreased maximum load-carrying capacity and increase stiffness at the expense of ductility. Lastly, the inclusion of curves gradually.

4

Nonlinear hygrothermal effects on the vibrations of a magnetostrictive viscoelastic laminated sandwich plate resting on an elastic medium

Zenkour Ashraf M., El-Shahrany Hela D.

Archives of Civil and Mechanical Engineering

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2021

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Vol. 21, no. 2

692--706

EN

In engineering applications, composite structures supported by elastic foundations are being vastly utilized in various operating environmental conditions. The nonlinear hygrothermal effect on vibration analysis of a magnetostrictive viscoelastic laminated composite sandwich plate rested on two-parameter Pasternak’s foundations is studied in the present article. The material properties of the viscoelastic plate’s layers are considered based on the Kelvin–Voigt model. The governing equation system is derived according to Hamilton’s principle. The analytical solution is obtained to study influences of the hygrothermal change, half wave number, magnitude of the feedback control gain, aspect ratios, thickness ratio, and structural viscoelastic damping coefficients on vibration damping characteristics of the plate including the frequencies, the damping rate, and the deflection. The obtained results indicate that the natural frequency and deflection reduce with increasing the structural viscoelastic damping value. The plate takes a long time for suppressing its vibration due to increasing the hygrothermal factor.

5

Dynamic damage analysis of a ten-layer circular composite plate subjected to low-velocity impact

Raissi Hamed

Archives of Civil and Mechanical Engineering

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2021

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Vol. 21, no. 3

158--199

EN

A new theoretical solution is presented to determine the stress distribution in a ten-layer simply-supported circular composite plate subjected to the low-velocity impact. The aim of the current study is the investigation of the dynamic analysis of the composite plate when a cylindrical impactor hits the top layer of the plate with an initial velocity of 1 m/s. The plate is made of two adhesive layers adhere two aluminum layers to a six-layer carbon-epoxy laminated plate. The classical non-adhesive elastic contact theory and Hunter's relationship are used to simulate the contact behavior in terms of time and contact radius. By using Hamilton's principle and Layerwise theory, thirty-two equations of motion are derived. Moreover, Johnson–Cook’s criteria, the plastic simulation model, the normal stress–strain failure criterion theory were used for failure analysis of the aluminum, adhesive, and carbon-epoxy layers, respectively. The numerical method was used to solve the thirty-two differential equations of motion based on the finite difference method. Moreover, the relationship between stress and strain is re-written in the numerical code so that the failure criterion theories are satisfied. Moreover, according to the defined failure criterion for each layer, the damage is checked at the end of every time step. In addition, the damping behavior of the composite plate after applying the contact pressure caused by the impact was also investigated. The results showed that the impact resulted in residual stress in the plate.

6

Analytical solution of the electro-mechanical flexural coupling between piezoelectric actuators and flexible-spring boundary structure in smart composite plates

Gohari Soheil, Mozafari F., Moslemi N., Mouloodi Saeed, Sharifi S., Rahmanpanah Hadi, Burvill Colin

Archives of Civil and Mechanical Engineering

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2021

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Vol. 21, no. 1

546--570

EN

An analytical solution has been developed developed in this research for electro-mechanical flexural response of smart laminated piezoelectric composite rectangular plates encompassing flexible-spring boundary conditions at two opposite edges. Flexible-spring boundary structure is introduced to the system by inclusion of rotational springs of adjustable stiffness which can vary depending on changes in the rotational fixity factor of the springs. To add to the case study complexity, the two other edges are kept free. Three advantages of employing the proposed analytical method include: (1) the electro-mechanical flexural coupling between the piezoelectric actuators and the plate’s rotational springs of adjustable stiffness is addressed; (2) there is no need for trial deformation and characteristic function—therefore, it has higher accuracy than conventional semi-inverse methods; (3) there is no restriction imposed to the position, type, and number of applied loads. The Linear Theory of Piezoelectricity and Classical Plate Theory are adopted to derive the exact elasticity equation. The higher-order Fourier integral and higher-order unit step function differential equations are combined to derive the analytical equations. The analytical results are validated against those obtained from Abaqus Finite Element (FE) package. The results comparison showed good agreement. The proposed smart plates can potentially be applied to real-life structural systems such as smart floors and bridges and the proposed analytical solution can be used to analyze the flexural deformation response.

7

Experimental study on fatigue failure evolution in composite plate monitored by wave propagation method

Stawiarski Adam, Barski Marek, Muc Aleksander

Vibrations in Physical Systems

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2020

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Vol. 31, nr 2

art. no. 2020227

EN

In this study, the elastic wave propagation method is used to observe the initiation and evolution of the fatigue failure form in the multilayered composite plate with an elliptical hole. The experimental tests with the use of active, pitch-catch elastic wave measurement techniques are used during the fatigue test of the composite specimens. The fatigue tests were preceded by the numerical, finite element analysis of the elastic wave propagation phenomenon in a composite plate with an elliptical hole. The sequential measurement related to the number of cycles during the fatigue tests was assumed. The time of flight (ToF) and amplitude change was monitored by piezoelectric sensors localized in the area of predictable failure form evolution. The analysis of the dynamic response of the structure under fatigue loading conditions by a relatively small number of piezoelectric transduces allows us to build cost-effective Structural Health Monitoring (SHM) system for damage detection and monitoring of the failure form evolution.

8

Dynamic stability of mechanically and thermally loaded three-layered annular plate with viscoelastic core

Pawlus Dorota

Vibrations in Physical Systems

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2020

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Vol. 31, nr 2

art. no. 2020223

EN

The problem of dynamic stability of composite three-layered annular plate with viscoelastic core is the subject of the consideration. Plate composed of thin outer layers and soft core is loaded quickly in time with forces compressing facings and with temperature gradient in radial direction. Two kinds of plate support system are analysed: plate slideably clamped in thermo-mechanical problem and plate clamped on both edges in thermal analysis. The analytical and numerical solution, which is based on the orthogonalization and finite difference methods includes axisymmetric and asymmetric forms of buckling and rheological properties of plate core.

9

The influence of Helmholtz and Golay coil homogenity on rectangular plate bending

Kędzia Piotr, Kosma Zbigniew

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2020

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Vol. 24, No 1

5--16

EN

The subject of the paper is a rectangular plate. The structure of the plate issymmetrical. The plate is made of a cellular structure of a core and two external faces. There isferrofluid in each cell of the porous core. The core is made of polyethylene foam and two facesare polyurethane sheets. It is assumed that cells in the core are regular and dense and the facesare thin, therefore, a plate filled in with ferrofluid can be treated as homogeneous. The plateis placed in the magnetic field. The magnetic field is generated by two systems of coils – theHelmholtz coil (HC ) and the Golay coil (GC). The former generates an almost fixed magneticfield in the considered volume (where the plate is placed), and the latter generates a gradientmagnetic field. The changing size of each subsystem of magnetic field coils, the distribution andstrength of the magnetic field change as well. The magnetic field induces loads in the plate,both perpendicular and in plane. The plate bending function is approximated by the bicubicspline function presented by normalized B-spline functions. The influence of changes in thehomogeneity volume and the magnetic field strength (by changing the coil size) on the platebending is analyzed in the paper. The results of the analysis are presented in tables and figures.

10

A comparative analysis of artificial intelligence-based methods for fault diagnosis of mechanical systems

Moghaddam Reihaneh Kardehi, Yazdan Navid Moshtaghi

Mechanics and Mechanical Engineering

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2019

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Vol. 23, nr 1

113--124

EN

The present research studied fault diagnosis of composite sheets using vibration signal processing and artificial intelligence (AI)-based methods. To this end, vibration signals were collected from sound and faulty composite plates. Using different time-frequency signal analysis and processing methods, a number of features were extracted from these signals and the most effective features containing further information on these composite plateswere provided as input to different classification systems. The output of these classification systems reveals the faults in composite plates. The different types of classification systems used in this research were the support vector machine (SVM), adaptive neuro-fuzzy inference system (ANFIS), k-nearest neighbor (k-NN), artificial neural networks (ANNs), Extended Classifier System (XCS) algorithm, and the proposed improved XCS algorithm. The research results were reflective of the superiority of ANFIS in terms of precision,while this method had the highest process duration with an equal number of iterations. The precision of the proposed improved XCS methodwas lower than that of ANFIS, but the duration of the processwas shorter than the ANFIS method with an equal number of iterations.

11

Sensitivity of composite structure with directional properties of annular three-layered plate mechanically and thermally loaded

Pawlus D.

Mechanics and Mechanical Engineering

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2018

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Vol. 22, nr 3

691--702

EN

Paper presents the sensitivity of the three-layered plate structure on the acting of mechanical and thermal loads. The cases of the annular plates, whose individual layers: facings and core have homogeneous building and/or heterogeneous one expressed by the variable material properties in radial direction have been examined. Numerical investigations have been carried out modelling the select examples of plate structure with the use of the finite element method. Plate is loaded in the plane of facings or is subjected to the flat temperature field. The evaluation of the structure sensitivity has been carried out analysing the values of critical loads or critical temperatures and corresponding with them buckling modes. Numerous results presented in diagrams create the image of plate behaviours, show responses of plate structure and indicate on the means of structure designs, which can fulfil the expected conditions of plate work.

12

Prefabrykaty ścienne z kompozytów styrobetonowych – od idei do prototypu

Wesołowska M., Mrozik Ł., Gajewski J., Grzybowska A., Piekarski P., Szczepaniak P., Janicki J.

Materiały Budowlane

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2018

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nr 12

32--33

13

Analytical and experimental investigation on the free vibration of a floating composite sandwich plate having viscoelastic core

Rezvani S. S., Kiasat M. S.

Archives of Civil and Mechanical Engineering

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2018

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Vol. 18, no. 4

1241--1258

EN

This paper focuses on the free vibration analytical solution of a composite sandwich plate consisting of woven carbon laminated faces and a viscoelastic foam core. In addition to the dry condition, a case of floating on bounded water is considered for the sandwich plate not only in analytical work but also in verification experiments. The equations of motion for the first-order shear-deformation plate in contact with the fluid are derived by using Hamilton's principle, and analytically solved using Navier's procedure. Bounded water boundary conditions and velocity potential function are used to describe the fluid motion. The viscoelastic properties of a marine PVC foam core are extracted from dynamic mechanical analysis. Frequency response function (FRF) method is applied in modal testing for measuring the natural frequencies of the dry and wet sandwich plates. Experimental results demonstrate the validity of the analytical results. The effects of the foam core behavior, core thickness, plate dimension ratio, and the fluid density on the natural frequencies are examined and discussed. The decrease of the fundamental mode natural frequency with the presence of the viscoelastic foam core is more prominent for the dry sandwich plate with respect to the wet one already damped by water.

14

Współczesne metalowe elewacje perforowane

Żwirek P.

Przegląd Budowlany

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2017

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R. 88, nr 3

34--41

PL

Stosowanie elewacji perforowanych umożliwia uzyskanie elewacji nadających bryle budynku indywidualny charakter. Spośród dużej liczby dostępnych na rynku wyrobów budowlanych materiałów elewacyjnych największe możliwości w zakresie formowania kształtu pojedynczego elementu okładzinowego, stopnia skomplikowania wzoru perforacji i jej intensywności zapewniają okładziny metalowe. Znajomość właściwości materiałów oraz technologii produkcji elementów perforowanych jest kluczowa dla uzyskania estetycznych i poprawnych technicznie, a jednocześnie akceptowalnych ze względu na koszty produkcji rozwiązań. W pracy omówiono wybrane zagadnienia związane z projektowaniem i wykonaniem metalowych elewacji perforowanych.

EN

Use of perforated elevations makes it possible to obtain elevations which provide the body of a building with an individual character. Out of a great number of elevation materials available on the construction market, the greatest possibilities in the scope of forming the shape of a single facing element, degree of complexity of the perforation pattern and its intensity, are provided by metal facings. Knowledge of properties of materials as well as of production technologies of perforated elements plays a key role in obtaining aesthetic and technically correct solutions, which at the same time are acceptable in terms of production costs. The paper discusses selected issues connected with designing and creation of perforated metal elevations.

15

Metalowe przegrody i obudowy ścian oraz dachów. Cz.3 Wyroby z metali nieżelaznych

Kowalski D.

Builder

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2017

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R.21, nr 8

80--83

PL

Metale kolorowe, nieoparte w swej budowie chemicznej na pierwiastku żelaza, jakimi są aluminium, cynk oraz miedź, stanowią dobrą, choć zdecydowanie droższą, alternatywę materiałową powszechnie stosowaną w pracach zarówno okładzinowych, jak i konstrukcyjnych wielu współczesnych budynków. Materiały te cenione są za ich odmienne właściwości w stosunku do wyrobów stalowych, w tym odporność na korozję, wygląd, charakter, jaki nadają obiektom. Inny aspekt to warunki ich stosowania, które wymagają czasami odmiennych metod obchodzenia się z wyrobami powstałymi z tych materiałów. W artykule opisano wybrane aspekty stosowania najpopularniejszych metali nieżelaznych w lekkich obudowach ścian i dachów.

16

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

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2017

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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.

17

Tolerance modeling of dynamic behavior of thin plates with dense system of ribs in two directions

Michalak B., Rabenda M.

Archives of Civil and Mechanical Engineering

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2017

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Vol. 17, no. 2

222--230

EN

The subject of this paper are thin composite rectangular plate. The plates are made of two families of ribs and homogeneous material of a matrix. The main feature of the considered plates is, that a distance between the ribs is comparable to the thickness of the plate. The widths of the ribs can vary slowly in the midplane of the plate. This allows you to get a desirable frequency of natural vibrations of the plate. The formulation of averaged model equations is based on the tolerance averaging approach (Wozniak et al. 2008, 2010). The general results of the contribution are illustrated using the analysis of natural vibrations of the plates under consideration. It will be carried out validation of the obtained mathematical model by comparison of results from obtained model equations with results from finite elements method (Abaqus program).

18

Trwałość elewacyjnych płyt kompozytowych z okładzinami z blachy aluminiowej

Wójtowicz M.

Przegląd Budowlany

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2016

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R. 87, nr 5

54--56

PL

Elewacyjne wyroby z aluminium znajdują powszechne zastosowanie w budownictwie, szczególnie do wykonywania okładzin wentylowanych. Jako wykończenie dużych powierzchni stosuje się odpowiednio wyprofilowane płyty kompozytowe, których zewnętrzne warstwy stanowią zabezpieczone blachy aluminiowe. Do oceny trwałości porównano płyty kompozytowe z blachami ze stali ocynkowanej i powlekanej metodą „coil coating”.

EN

Facade aluminum products are widely used in construction, especially for making ventilated claddings. Composite panels appropriately contoured are used as a finishing of large surfaces. The outer layers on these panels are the protected aluminum sheets. For the purpose of evaluation of the durability, two kinds of composite panels: with the sheets of galvanized steel and coated using the „coil coating” methods, were compared.

19

Effects of elastically restrained edges on FG sandwich annular plates by using a novel solution procedure based on layerwise formulation

Alipour M. M.

Archives of Civil and Mechanical Engineering

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2016

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Vol. 16, no. 4

678--694

EN

In practical applications, sandwich plates are often connected to other members, supported by damaged clamped/simply supported boundary conditions or supported by elastic restraints. Therefore, the mentioned structures may not always be simulated by the classical boundary conditions, i.e., ideal simply supported, clamped and free edges. Also, these structures may be subjected to various loads. In this study, for the first time, a novel economical analytical solution procedure is presented for axisymmetric static analysis of sandwich annular plates, by using the layerwise and 3D elasticity theories. Based on the proposed approach, functionally graded sandwich annular plates with various elastically restrained edges under arbitrary distributed loads may be analyzed and all of the displacements and stresses components may be exactly achieved. Also, imposed loads at the boundaries may be evaluated. Transverse shear and normal stresses boundary conditions on the top and bottom of the sandwich plate and the interlaminar continuity conditions of the in-plane displacement, transverse shear and normal stresses are exactly satisfied. Accuracy and efficiency of the presented solution procedure are demonstrated by comparing the obtained results for sandwich plates with the classical edge conditions as some special cases of the elastic supports with results of the three-dimensional theory of elasticity.

20

Innowacyjna technologia wytwarzania płyt wielowarstwowych stosowanych w mobilnych systemach transportu specjalistycznego

Lodwik D., Malesa W., Wiktorski Z.

Logistyka

|

2015

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nr 4

4499--4508, CD2

PL

W pracy przedstawiono technologię wytwarzania wielowarstwowych, wielkogabarytowych płyt kompozytowy kształtowanych metodą prasowania próżniowego. Wskazano zalety i możliwości zastosowania płyt kompozytowych, jako nowoczesnego materiału do budowy systemów transportu specjalnego przeznaczenia zastępującego tradycyjne zabudowy stalowe i aluminiowe. Przedstawiono przykłady rozwiązań konstrukcyjnych mobilnych systemów transportu specjalistycznego. W budowie ścian, dachów, podłóg, drzwi użyto płyt kompozytowych o szczególnych wymaganiach wytrzymałościowych, estetycznych i higienicznych. Dzięki zastosowaniu lekkich i wytrzymałych płyt kompozytowych i zastosowanej technologii ich łączenia uzyskano wytrzymałe na skrajne warunki atmosferyczne, sztywne, lekkie i funkcjonalne pozbawione wszelkich mostków termicznych, o bardzo dobrych parametrach izolacyjnych mobilne systemy kontenerowe.

EN

At work shows the manufacturing technology of multi-layered, large size composite plate, shape with vacuum pressing method. Indicated advantages and opportunities to use of composite panels as modern material to build special transport systems to replace traditional steel and aluminum buildings. Shows examples of design solutions to mobile systems of specialist transport. In the constructions of walls, roofs, floors and doors used composite plate with special endurance esthetic and hygienic requirements. Thanks to the use of light and durable composite plate and technology to combine them to gained resistant to bad weather conditions, rigid, light and functional devoid of any thermal bridge with very good insulation parameters of mobile container systems.