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Open access

Piotr Lacki, Przemysław Kasza and Anna Derlatka

Abstract

The aim of the work was to perform numerical analysis of a steel-concrete composite floor located in a LIPSK type building. A numerical model of the analytically designed floor was performed. The floor was in a six-storey, retail and service building. The thickness of a prefabricated slab was 100 mm. The two-row, crisscrossed reinforcement of the slab was made from φ16 mm rods with a spacing of 150 x 200 mm. The span of the beams made of steel IPE 160 profiles was 6.00 m and they were spaced every 1.20 m. The steelconcrete composite was obtained using 80×16 Nelson fasteners. The numerical analysis was carried out using the ADINA System based on the Finite Element Method. The stresses and strains in the steel and concrete elements, the distribution of the forces in the reinforcement bars and cracking in concrete were evaluated. The FEM model was made from 3D-solid finite elements (IPE profile and concrete slab) and truss elements (reinforcement bars). The adopted steel material model takes into consideration the plastic state, while the adopted concrete material model takes into account material cracks.

Open access

Marinela Inţă, Achim Muntean and Cristian Petrianu

Abstract

The paper intends to implement the use of theoretical models and computer aided simulation based on FEM for improving the teaching of cutting metals theory for the students of Machine Manufacturing Technologies and Machine Tools. The advantage of simulation, especially animated is to transpose the normal classroom into a virtual model where the skills can be evaluated under similar realistic conditions. It helps the students to be able to face the complexity of the real complex processes inside the production environment. A review of the most important models in cutting processes shows that the majority of the researches in this field tend to replace the traditional methods of calculating the cutting data parameters based on mathematical models with new complex models. The paper tries to relieve the importance of using the FEM models and simulation software for a better understanding of the process and also for providing more accurate and more detailed information. In the case studied in this paper a series of experimental models were performed for a validation of the theoretical models created by comparing the results. The advantages of using 2D and 3D animated models in the teaching and training process are also mentioned in the paper.

Open access

S. Sobieszczyk, W. Wojnicz and B. Nowak

FEM Approach to Estimate the Behaviour of Biocomposite Metal-Surface Coating Systems

A three dimensional (3D) model of biocomposite metal-surface coating system, which is influenced by known external forces, is proposed. This model consists of the metallic substrate (Ti6A14V) and the hydroxyapatite (HA) coating. Using FEM (finite element method), strain-stress maps of model were generated for investigating relations between the extreme stress of HA coating and the magnitude of external force and the thickness of the coating. The analysis of numerical simulations results confirms that the system with the greatest coating thickness (i.e. 10-3 m) has the least extreme stress in this surface coating.

Open access

Andrzej Kurek, Adam Niesłony and Marta Kurek

Abstract

The paper contains a numerical analysis of interface zone steel-titanium bimetal obtained by explosive cladding method. Due to the waviness of the zone, and various properties of the constituent material of the materials type contain structural notch. Therefore it is important inter alia in terms of presentation of the results of fatigue are the maximum stresses that occur just in the area of the zone. In the paper the stress concentration factor and the proposed method of modelling the joint zone of a sinusoidal profile, characterized by the same coefficient of stress concentration at the actual profile.

Open access

Ondřej Bílek, Imrich Lukovics, David Sámek and Jana Knedlová

Abstract

Residual stresses lower the utility value of plastic parts. Determination of the induced stresses can help deal with them. Measurements are time-consuming and expensive. A new approach to measuring residual stresses, such as indentation measurement, can lead to the simple determination of residual stresses. The paper shows the relationship between the condition of injection moulding, the subsequent residual stress, and hardness through thickness. The computer model displays the field and magnitude of residual stress in the samples. The model results are then compared to measured parameters after indentation and the magnitude of residual stress determined by the standard hole drilling method.

Open access

Milan Sokol, Petra Velísková, Ľuboš Rehák and Martin Žabka

Abstract

The aim of the work is oriented towards the simulation or modeling of the lumbar and thoracic human spine as a load-bearing 3D system in a computer program (ANSYS). The human spine model includes a determination of the geometry based on X-ray pictures of frontal and lateral projections. For this reason, another computer code, BMPCOORDINATES, was developed as an aid to obtain the most precise and realistic model of the spine. Various positions, deformations, scoliosis, rotation and torsion can be modelled. Once the geometry is done, external loading on different spinal segments is entered; consequently, the response could be analysed. This can contribute a lot to medical practice as a tool for diagnoses, and developing implants or other artificial instruments for fixing the spine.

Open access

Pavel Kraus, Juraj Úradníček, Miloš Musil and Michal Bachratý

Abstract

The evaluation of disk brake squeal is nowadays performed using Finite Element Model. In this standard procedure the thermal effects are omitted. The omission is done because of long computing time of fully coupled brake system thermo-structural transient analysis. This paper is presenting an effective uncoupled thermo-structural FEM procedure. This method is applied on a pin-on-disc system and its time effectiveness is compared to standard full coupled transient analysis.

Open access

M. Repka, J. Sládek, V. Sládek and M. Wünsche

Abstract

The finite element method (FEM) is developed for coupled thermoelastic crack problems if material properties are continuously varying. The weak form is utilized to derive the FEM equations. In conventional fracture theories the state of stress and strain at the crack tip vicinity is characterized by a single fracture parameter, namely the stress intensity factor or its equivalent, J-integral. In the present paper it is considered also the second fracture parameter called as the T-stress. For evaluation of both fracture parameters the quarter-point crack tip element is developed. Simple formulas for both fracture parameters are derived comparing the variation of displacements in the quarter-point element with asymptotic expression of displacement at the crack tip vicinity. The leading terms of the asymptotic expansions of fields in the crack-tip vicinity in a functionally graded material (FGM) are the same as in a homogeneous one with material coefficients taken at the crack tip.

Open access

Roman Gogola, Justín Murín and Juraj Hrabovský

Abstract

This paper contains results of transient analysis of airflow around the ACSR power line cross-section in unsymmetric multi-span. The forces applied to the power line are obtained from CFD simulations, where the wind induced vibration is studied. Effect of these forces to the maximal displacement of the power line and the maximal mechanical forces in the points of attachment are studied and evaluated.

Open access

Martin Magura

Abstract

Gas pipelines pass through different topographies. Their stress level is influenced not only by gas pressure, but also by the adjacent soil, the thickness of any covering layers, and soil movements (sinking, landslides). The stress level may be unevenly spread over a pipe due to these causes. When evaluating experimental measurements, errors may occur. The value of the resistance reserve of steel can be adjusted by a detailed analysis of any loading. This reserve can be used in the assessment of a pipeline’s actual state or in reconstructions. A detailed analysis of such loading and its comparison with the simple theory of elasticity is shown in this article.