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Search results for: POUNDING, TIMBER FRAME BUILDINGS, EARTHQUAKES, SEISMIC, FEM, NUMERCIAL MODELING, GROUND MOTIONS
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Review of historical buildings' foundations
PublicationThe paper presents in brief the history of foundation engineering with a particular regard to its development, applied techniques and materials. Different types of old foundations in relation to various soil conditions are considered. Basic methods of preservation of old foundations, with special emphasis given to their faults and advantages are discussed. Finally, some problems of the reuse of pre-existing foundations are raised....
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Polyurethane/ground tire rubber composite foams based on polyglycerol: processing, mechanical and thermal properties
PublicationDuring the synthesis of rigid polyurethane foams, petrochemical polyol was substituted with polyglycerol, the product of thermo-catalytic polycondensation of waste glycerol, resulting from biodiesel production. Two types of ground tire rubbers, untreated and thermo-mechanically reclaimed, were used to obtain ‘‘green’’ polyurethane-polyglycerol composite foams. Samples were prepared by a single-step method for the ratio of NCO/OH...
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Sparse autoregressive modeling
PublicationIn the paper the comparison of the popular pitch determination (PD) algorithms for thepurpose of elimination of clicks from archive audio signals using sparse autoregressive (SAR)modeling is presented. The SAR signal representation has been widely used in code-excitedlinear prediction (CELP) systems. The appropriate construction of the SAR model is requiredto guarantee model stability. For this reason the signal representation...
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Non-Destructive Testing of the Longest Span Soil-Steel Bridge in Europe—Field Measurements and FEM Calculations
PublicationThe article describes interdisciplinary and comprehensive non-destructive diagnostic tests of final bridge inspection and acceptance proposed for a soil-steel bridge made of corrugated sheets, being the European span length record holder (25.74 m). As an effect of an original concept a detailed and precise information about the structure short-term response was collected. Periodic diagnostics of bridge deformations was done one...
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A Mesh Deformation Technique Based on Solid Mechanics for Parametric Analysis of High-Frequency Devices With 3-D FEM
PublicationIn this paper, a versatile technique for mesh defor- mation is discussed, targeted at the electromagnetic (EM) field simulation of high-frequency devices using the 3-D finite element method (FEM). The approach proposed applies a linear elasticity model to compute the displacements of the internal mesh nodes in 3-D when the structure geometry is changed. The technique is compared with an alternative approach...
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Reliability Modeling for SPMD and DAC Applications in MERPSYS
PublicationIn this chapter we shall see a method for modeling of reliability of application execution in the MERPSYS system, and the results of reliability simulation of the same SPMD and DAC application which we have previously presented in this book. Unlike energy usage modeling and modeling of execution efficiency we could not compare the reliability model and simulation results to real experiment just because the experiment would last too...
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Behaviour of asymmetric structures with base isolation made of Polymeric Bearings
PublicationEarthquake-induced ground motions are the most severe and unpredictable threats to the structures all around the world. Seismic excitations cause a lot of damage in a wide variety of ways, leaving thousands of casualties in their wake. During the last few years alone, the world has witnessed many major earthquakes, five of which have caused far-reaching consequences of a national scale for Haiti (January 2010), Chile (February...
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Configuration of the reference stations as the element of national reference frame reliability
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Behaviour of Asymmetric Structure with Base Isolation Made of Polymeric Bearings
PublicationEarthquake-induced ground motions are the most severe and unpredictable threats to the structures all around the world. Seismic excitations cause a lot of damage in a wide variety of ways, leaving thousands of casualties in their wake. Due to randomness of earthquake occurrence, lack of visible causes and their power of destructiveness, structural engineers need to develop new technical solutions and protection systems against...
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Study of displacements of a bridge abutment using FEM
PublicationSteel sheet piles are often used to support excavations for bridge foundations. When they are left in place in the permanent works, they have the potential to increase foundation bearing capacity and reduce displacements; but their presence is not usually taken into account in foundation design. In this article, the results of finite element analysis of a typical abutment foundation, with and without cover of sheet piles, are presented...
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A two-scale (FEM-DEM) approach for concrete
PublicationArtykuł omawia dwu-skalowe podejście do betonu przy wykorzystaniu modelu Mes i DEM. Metodę elementów skończonych zastosowano na poziomie makro. Na poziomie mikro zastosowano metodę elementów dyskretnych. Macierz sztywności wyznaczono na podstawie tensora naprężeń wyznaczonego w skali mikro. Wyniki numeryczne dwusalowe porównano z wynikami dyskretnymi dla całego obszaru.
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THE CREATIVE AND SYMBOLIC FUNCTIONS OF DAYLIGHT IN THE ART MUSEUM BUILDINGS OF THE 21st CENTURY
PublicationThe paper presents the results of the study on the current extent of daylight use in contemporary buildings of art museums, focusing especially on the possibilities of aesthetic function. A case study and critical analysis were used as the research method. Selected, representative examples of museums of the 21st century are discussed with regard to the creative and functional use of daylight and the application of advanced technology....
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Modeling BIM Objects From Point Clouds. Examples
PublicationThe article presents several ways to obtain BIM (Building Information Modeling) models from point clouds using standard commands in Revit 2018. In Revit geometric forms are possible to obtain in project, family or conceptual environments. Efficient modeling requires knowledge of methods of creating families and components in these environments and ways to combine them. Modeling methods with system and loadable families are presented,...
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Modification of Ground Tire Rubber—Promising Approach for Development of Green Composites
PublicationGround tire rubber (GTR) was mechano-chemically modified using a road bitumen 100/150 and two types of organic peroxides: di-(2-tert-butyl-peroxyisopropyl)-benzene (BIB) and dicumyl peroxide (DCP). The impact of used additives on reactive sintering efficiency and physico-mechanical properties of modified GTR was investigated using oscillating disc rheometer measurements, followed by tensile tests and swelling behavior studies....
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Application of Support Vector Machine for Determination of Impact of Traffic-Induced Vibrations on Buildings
PublicationThe aim of the article is to present an algorithm of Support Vector Machine created to forecast the impact of traffic-induced vibrations on residential buildings. The method is designed to classify the object into one of two classes. The classification into the first class means that there is no impact of vibrations on the building, while classification to the second class indicates the possible influence and suggests the execution...
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Crack Detection in Metallic Surfaces Based on Dumbbell-Shaped Defected Ground Structures in Microstrip Technology
PublicationIn this paper, a novel crack detection sensor using a microstrip loaded with a Dumbbell-Shaped Defected Ground Structure (DS-DGS) is proposed. The sensing element is etched in the ground plane of a microstrip line and it is easy to fabricate. The electromagnetic (EM) field of the microstrip couples to the DS-DGS, thus demonstrating a bandstop behavior. It is shown that in the presence of a crack in a metallic surface underneath the...
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Efficiency of thermomechanical reclaiming of ground tire rubber conducted in counter-rotating and co-rotating twin screw extruder
PublicationIn this article the results of research on a continuous thermomechanical reclaiming process of ground tire rubber (GTR) conducted in a twin screw extruder are presented. The effects of the rotation direction (co-rotating/counter-rotating), design of co-rotating plasticizing units and the rotational speed of the screws on the extruder working parameters, sol fraction and the degree of reclaiming in the obtained products were described....
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Various cases of preservation and adaptive reuse Heritage Buildings in the Port of Gdynia
PublicationThe port of Gdynia contains a diverse range of heritage assets, starting with its spatial layout which is an urban concept designed in the first half of the 1920s. It is important to point out, this historically-shaped harbor space is preserved in its general idea and still functioning in port activities. Another significant element is the structural, technological solution which was the basis for constructing the entire port area...
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An MOR Algorithm Based on the Immittance Zero and Pole Eigenvectors for Fast FEM Simulations of Two-Port Microwave Structures
PublicationThe aim of this article is to present a novel model-order reduction (MOR) algorithm for fast finite-element frequency-domain simulations of microwave two-port structures. The projection basis used to construct the reduced-order model (ROM) comprises two sets: singular vectors and regular vectors. The first set is composed of the eigenvectors associated with the poles of the finite-element method (FEM) state-space system, while...
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Museum of the Second World War in Gdansk as an Example of Contemporary Design Trends in Museum Buildings
PublicationAt a time when history gives us one of the last opportunities to confront our knowledge of World War II, with the knowledge of people living in those days, there are buildings created with strong transmission not only architectural, but also of a great emotional load. At the same time, when the political system does not forbid to speak openly about the past period, and the technology allows you to create structures, about which...
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DYNAMIC ANALYSIS OF THE IMPACT OF VIBRATION ON HISTORICAL BUILDINGS - AN OWN PROJECT OF EXTERNAL STAIRCASE
PublicationThis article presents numerical simulations that concern modeling of interaction of the external staircase’s construction with the observation deck on historic water tower located at Gdansk University of Technology. The interaction occurring according to various methods of the staircase's construction support on the wall of the historic tower was compared. The external staircase that allows for entering onto the monument was subjected...
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Software Modeling from the Perspective of Intuitive Information Processing
PublicationThere is psychological evidence that humans process information not only consciously but also intuitively. Intuitive information processing is present also during the activities related to software modeling. The goal of this paper is to analyze software modeling from the perspective of theories which describe intuitive (nonconscious, implicit) information processing. The paper includes presentation of relevant psychological theories,...
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Induction machine behavioral modeling for prediction of EMI propagation.
PublicationThis paper presents the results of wideband behavioral modeling of an induction machine (IM). The proposed solution enables modeling the IM differential- and common-mode impedance for a frequency range from 1 kHz to 10 MHz. Methods of parameter extraction are derived from the measured IM impedances. The developed models of 1.5 kW and 7.5 kW induction machines are designed using the Saber Sketch scheme editor and simulated in the...
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Ground tire rubber functionalization as a promising approach for the production of sustainable adsorbents of environmental pollutants
PublicationWaste tires management and further utilization are currently one of the biggest concerns regarding the environment and human health protection. At present, shredding, grinding, or pulverization of waste tires are the most popular options for industrial recycling. Although many solutions for ground tire rubber (GTR) applications were checked and verified so far, their further implementation at an industrial scale is still very limited....
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Empirical Relationship Describing Total Convective and Radiative Heat Loss in Buildings
PublicationOn the basis of theoretical considerations of convective-radiative heat transfer, a relationship was developed enabling the total convective and radiative heat flux QC+R emitted from any object at tw and its surroundings at t∞ to be calculated from known values of the surface temperature of such an object, i.e., the known temperature difference Δt=tw - t∞ and average air temperature Tav. This relationship is applied to thermal...
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Issues relating to the efficient Application of passive solar protection in multi-family residential buildings
PublicationThe following article is intended to discuss the issues concerning the introduction of passive measures aimed at improving solar protection in multi-family buildings. A system of classifying these methods into two groups of solutions (architectural and material-building) was applied. The first group includes issues concerning facade design, the spatial features of which (such as loggias, balconies and other overhangs) can be treated...
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Triangulation-based Constrained Surrogate Modeling of Antennas
PublicationDesign of contemporary antenna structures is heavily based on full-wave electromagnetic (EM) simulation tools. They provide accuracy but are CPU-intensive. Reduction of EM-driven design procedure cost can be achieved by using fast replacement models (surrogates). Unfortunately, standard modeling techniques are unable to ensure sufficient predictive power for real-world antenna structures (multiple parameters, wide parameter ranges,...
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THE CONCEPT OF MODELING OF SNOW IMPACT ON THE STRUCTURE OF THE SUSPENDED TAURON ARENA ROOF IN CRACOW
PublicationThe article presents studies and numerical simulations on modeling snow influence on TAURON ARENA suspended roof structure in Cracow. The scope of work includes experimental tests, functions solutions taking into account various cases of snow impact according to PN and EC, as well as numerical simulations for the sport and entertainment arena in the Czyzyny district. The FEM roof structure model developed in the SOFISITK software...
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Investigation of volatile low molecular weight compounds formed during continuous reclaiming of ground tire rubber
PublicationGround tire rubber was thermo-mechanically reclaimed at different temperature conditions (80, 120, 160 °C) using a co-rotating twin screw extruder. The progress of ground tire rubber reclaiming was evaluated with specific mechanical energy, sol fraction and thermogravimetric analysis. Volatile organic compounds (VOCs) including volatile sulfur compounds (VCSs) released from ground tire rubber and ground tire rubber after reclaiming...
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FINITE GROUND CPW-FED UWB ANTENNA OVER THE METALLIC CYLINDRICAL SURFACES
PublicationThe investigation of finite ground coplanar fed ultra-wideband (UWB) antenna and the influence of its curvature and the proximity of circular metallic screen on the reflection coefficients and radiation characteristics is presented. The antenna is composed of two circular coplanar strips which enclose slot aperture of similar shape and is designed on a thin and flexible substrate which allows its bending. The antenna configuration...
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Ground-based radiolocation system - AEGIR
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Ground improvement with in situ Soil Mixing
PublicationOmówiono metodę wzmacniania słabego gruntu za pomocą technologii wgłębnego mieszania na sucho i mokro. W metodzie mokrej stosuje się składniki wiążące (głownie cementy) wymieszane z wodą, podawane w formie zaczynu. W metodzie suchej materiały wiążące podawane są w postaci sproszkowanej z udziałem sprężonego powietrza. Przedstawiono główne obszary zastosowania w geotechnice oraz podano przykłady kilku realizacji.
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The method of detection of electromagnetic fields in ground
PublicationW prezentowanej metodzie, detekcja pola polega na pomiarach i analizie zmian rozkładu potencjału. Różnice potencjałów są mierzone jako napięcie pomiędzy elektrodami umieszczonymi w różnych pozycjach na powierzchni ziemi. Analiza tych napięć przy pomocy krótkoczasowej transformaty Fouriera STFT umożliwia wyznaczenie zmian spektralnej gęstości mocy sygnału w funkcji czasu. Ten rodzaj łącznej analizy czasowo-częstotliwościowej daje...
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In search of a common ground for the space sciences
PublicationThe paper discusses the relations between various aspects of human activities performed in space, taking into consideration the past, present and future contexts. Interdisciplinarity and integrity of technological issues combined with legal and management issues were emphasized. Consequently, it was recognized that it is necessary to build a network of universities, research-and-development companies and engineering companies....
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Ionosphere variability II: Advances in theory and modeling
PublicationThis paper aims to provide an overview on recent advances in ionospheric modeling capabilities, with the emphasis in the efforts relevant to electron density variability. The discussion spans a wide range of model formulations (e.g., from purely empirical to physics-based ones and data-driven approaches) seeking for advances or gaps with regard to present challenges. This discussion is further supported by consideration of the...
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Stability and initial post-buckling behaviour of frame system with vertical bracings
PublicationStalowe hale są budowane jako układ ram płaskich połączonych stężeniami dachowymi i stężeniami pionowymi w postaci krzyżujących się prętów. W pracy przedstawiono analizę stateczności i zachowania pokrytycznego takiego układu poddanego działaniu obciążeń pionowych. Korzystając z warunków stacjonarności całkowitej energii potencjalnej wykazano, że punkt bifurkacji utraty stateczności jest niesymetryczny i niestateczny. Oznacza to,...
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Elastic wave propagation in frame structure in the context of structural health monitoring
PublicationPraca dotyczy propagacji fal sprężystych r konstrukcji ramowej w ośrodku typu belka Timoszenki. Do obliczeń numerycznych wykorzystano wielowęzłowe spektralne elementy skończone klasy C0. Omówiono algorytm całkowania po czasie i sformułowano wnioski dotyczące liczby węzłów na długość fali.
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Relationship between saw blade teeth wear and kinematics of frame sawingmachines
PublicationPrzedstawiono rezultaty badań zużycia ostrzy pił trakowych i wpływ kinematyki pilarki ramowej na rozkład zużycia poszczególnych ostrzy pił.
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Visual Dimensions of Modeling Languages in Interdisciplinary Perspective
PublicationUżyteczność języków modelowania wizualnego zależy od notacji. Notacja może być postrzegana jako zestaw wizualnych komponentów, które w określony sposób oddziałują na ludzkie oko i ludzki mózg. Referat przedstawia analizę interdyscyplinarną wykonaną w celu lepszego zrozumienia wizualnych wymiarów języków modelowania. Wizualne wymiary pochodzą z teorii opisujących percepcję wzrokową, wizualizację danych oraz reprezentacje poznawcze....
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Comprehensive analysis of low-temperature methods for reclaiming of ground tire rubber
PublicationManagement of waste tires has become an important topic for decades. The lack of an effective method to manage the materials as mentioned above leads to illegal landfills. This problematic waste can be divided into two main categories depending on the physical condition of the waste: (i) partially used tires; (ii) end-of-life tires. While the first group can be reused or retreaded, the second group requires special measures to...
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Pounding force response spectrum under earthquake excitation
PublicationW artykule przedstawiono możliwość wykorzystania spektrum siły zderzenia jako zaproponowanego przez autora narzędzia pomocnego przy projektowaniu budynków narażonych na zderzenia podczas trzęsień ziemi. Przedstawione wykresy spektrów pokazały, iż właściwy dobór parametrów budowli, takich jak szerokość przerwy pomiędzy budynkami, okres drgań własnych konstrukcji, liczba tłumienia, masa, współczynnik ciągliwości, czy też przesunięcie...
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Structural pounding models with Hertz spring and nonlinear damper
PublicationW artykule przedstawiono porównanie możliwości wykorzystania dwóch modeli zderzeń: nieliniowego modelu lepkosprężystego i modelu Hertz'a z dodatkowym tłumieniem. Efektywność każdego z modeli zbadano porównując wyniki analiz numerycznych z wynikami badań eksperymentalnych. Wyniki pracy pokazują, iż zastosowanie nieliniowego modelu lepkosprężystego prowadzi do mniejszych błędów w przebiegach czasowych siły zderzenia oraz do mniejszych...
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Wear of Farm Buildings in Selected Farms
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Soil mechanics and old buildings foundations
PublicationPraca dotyczy sposobów fundamentowania obiektów zabytkowych. Przeanalizowano historyczny rozwój sposobów posadowienia poczynając od starożytności, poprzez średniowiecze aż do czasów nowożytnych. Omówiono charakterystyczne dla kolejnych okresów historycznych rodzaje fundamentów. Przedstawiono przykłady dobrego i złego fundamentowania.
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Mechanical response of buried High-Density Polyethylene pipelines under normal fault motions
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Simulation of Life Raft Motions on Irregular Wave - An Analysis of Situations Leading to Raft Capsizing
PublicationSuccessful rescue action at sea is based on a. o. a correct choice of rescue means and their reliability. Operational characteristics of life-saving appliances determine their performance in a given water area. Therefore they affect duration time of rescue action and decide this way on survival time of shipwrecked persons. This paper presents impact of characteristics of circular inflatable life rafts on their dynamics in a...
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Vertical motions damping model test of a lifeboat lowered onto a flat sea surface
PublicationThe article presents the experiment’s results of the lifeboat model lowered with an initial speed and then released to fall onto a flat water surface. The purpose of the research is to determine the trajectory of the vertical boat motion and describe it with a mathematical model. This is closely related to determining the damping factor since the vertical motion is damped and the lifeboat gets balanced and stops moving after some...
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ENTERPRISE ACTIVITIES MODELING BY BPMN NOTATION
PublicationDepending on the process behavior, available know-how and organizational goals, different techniques and tools can be used for business process modeling. We concentrate on e-commerce, and try to find the best marketing strategy for the sales process improvement. In the paper we present the multilayer approach to define enterprise scenarios. This allows us to collect the suitable knowledge necessary for enterprise analysis and improvement....
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Young’s modulus distribution in the FEM models of bone tissue
PublicationThis paper presents how differences of Young’s modulus in adjacent finite elements typical for organic materials such as bone tissue, influence stress calculating. Emphasizing high computational cost of variable Young’s modulus in parts of the model, where the number of finite elements has been raised, the authors wants to prove that new model of finite element which has variable Young’s modulus in its volume needs to be created....
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Numerical modeling and experimental validation of full-scale segment to support design of novel GFRP footbridge
PublicationThe paper contains analysis of full-scaled three meters long segment of a novel composite footbridge. Both numerical modeling and experimental validation were performed. Analyzed object is a shell type sandwich channel-like structure made of composite sandwich with GFRP laminates as a skin and PET foam as a core. Several static load schemes were performed including vertical and horizontal forces. In FEM analysis multilayered laminate...