Przeglądaj {{ collection }} wg Autor "Kamiński, M."

Teraz wyświetlane 1 - 4 z 4

Analytical and Numerical Reliability Analysis of the Pratt Steel Truss
(Wydawnictwo Politechniki Łódzkiej, 2021) Kamiński, M.; Błoński, R.
The main aim of this paper was to investigate a variation of the reliability index β for some steel truss girder depending with respect to its length and to check the differences in numerical results obtained with the use of numerical and analytical probabilistic calculations. Some small Pratt truss, which includes vertical members and diagonals that slope down towards its centre was selected to make such a comparison. The span of this truss has been adopted as the Gaussian input variable in this study, which is motivated by in situ observations and measurements statistics as well as by its nonlinear impact on the Serviceability Limit State. The basic probabilistic characteristics of the structural response have been determined using the 10th-order Iterative Generalized Stochastic Perturbation Method and using Monte-Carlo Simulation also. The very important aspects in this work are (i) a contrast of analytical and numerical results and (ii) stochastic analysis of the load capacity in this truss joints, i.e. the stresses in the welds. Numerical results presented here have been obtained by the Finite Element Method system Robot Structural Analysis Professional 2021 and also via symbolic computer algebra environment MAPLE.
Dynamic analysis of steel mast under some environmental uncertainties
(Wydawnictwo Politechniki Łódzkiej, 2022) Bredow, R.; Kamiński, M.
A concise and factual abstract is required. The abstract should state briefly the purpose of the research, the principal results and major conclusions. An abstract is often presented separately from the article, so it must be able to stand alone. For this reason, references should be avoided, but if essential, then cite the author(s) and year(s). Also, non-standard or uncommon abbreviations should be avoided, but if essential they must be defined at their first mention in the abstract itself.
Probabilistic Analysis of the 6061 Aluminium Alloy Tensile Test with Random Initial Microdefects
(Wydawnictwo Politechniki Łódzkiej, 2021) Strąkowski, M.; Kamiński, M.
The main aim of this paper was to investigate an application of the generalized higher order iterative generalized stochastic perturbation technique in numerical simulation of 6061 aluminum alloy plastic behavior with structural initial microdefects. Gurson-Tvergaard-Needleman constitutive porous material model implemented in ABAQUS system has been employed for this purpose with its 2D triangular and quadrilateral elements. A volume fraction f0 of the initial microdefects naturally appearing in the material has been adopted as the input random variable having symmetric but not necessary Gaussian distribution. A verification of its uncertainty influence on statistical scattering of material specimen deformations, stresses and void volume fractions has been carried out thanks to the common usage of the FEM system ABAQUS and computer algebra system MAPLE 2019. The 10th order Iterative Stochastic Perturbation Technique has been compared with Monte Carlo Simulations and Semi-Analytical Method to analyze uncertainty in extreme stresses and deformations within the tensioned material coupon.
Random Response of Steel Hall Subjected to the Dynamic Excitation by the Generalized Iterative Stochastic Perturbation Technique
(Wydawnictwo Politechniki Łódzkiej, 2021) Bredow, R.; Kamiński, M.
This work aims to analyze the random response of steel halls subjected to dynamic wind excitation. The investigated object has recently been erected in central Poland and its mathematical model has been created in Abaqus 2017 software. The model includes the warp of beam elements involved in the structure which adds additional value to this work. Dynamic analysis has been performed with the Hilber- Hughes-Taylor algorithm and recovered responses undergo further approximation in polynomial form for probabilistic analysis. Several uncertainties of mechanical and environmental nature are investigated. Generalized Iterative Stochastic Perturbation Technique has been contrasted with Monte Carlo Simulations and Semi-Analytical Approach. Conclusions from this comparison are discussed in this paper.