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Wznoszenie obiektu budowlanego jako zadanie interakcyjne i śledzące

Miedziałowski C., Siwik D.

Budownictwo i Inżynieria Środowiska

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2013

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Vol. 4, no. 1

53--60

PL

Konstrukcje budowlane trwale związane z gruntem, współpracują z nim w zakresie statyki i dynamiki. Odkształcalność gruntu powoduje, że stan naprężeniowo-deformacyjny w budowli zależy od wzajemnej interakcji konstrukcji i podłoża gruntowego. Z drugiej strony, obiekty budowlane wznoszone są etapami, wynikającymi z technologii i organizacji robót. Pierwszym etapem jest wykonanie wykopu, następnie posadowienie i realizacja kolejnych elementów konstrukcji. Model obliczeniowy w zadaniach dotyczących statyki lub dynamiki powinien uwzględniać zarówno przestrzenność układu, jak i interakcje jego elementów składowych oraz fakt postępującej budowy, to jest „śledzenie” jego kolejnych etapów. W artykule zostanie zaprezentowany własny, blokowy model, zbudowany na bazie metody elementów skończonych, wraz z przykładem obliczeniowym uwzględniającym etapowanie konstrukcji modelowego budynku ścianowego.

EN

The paper presents "tracking" model, taking into account the structures and subsoil interaction and stages of the building construction. The presented model, based on the finite element method, was built with the following problems: identification of the components of the model (structure, technology), mathematical model construction, realization of the calculations (calculation example), accuracy and convergence problems.

2

Interaction model for predicting bead geometry for Lab Joint in GMA welding process

Thao D.T., Kim I.S.

Archives of Computational Materials Science and Surface Engineering

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2009

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Vol. 1, nr 4

237-244

EN

Purpose: The prediction of the optimal bead geometry is an important aspect in robotic welding process. Therefore, the mathematical models that predict and control the bead geometry require to be developed. This paper focuses on investigation of the development of the simple and accuracy interaction model for prediction of bead geometry for lab joint in robotic Gas Metal Arc (GMA) welding process. Design/methodology/approach: The sequent experiment based on full factorial design has been conducted with two levels of five process parameters to obtain bead geometry using a GMA welding process. The analysis of variance (ANOVA) has efficiently been used for identifying the significance of main and interaction effects of process parameters. General linear model and regression analysis has been employed as a guide to achieve the linear, curvilinear and interaction models. The fitting and the prediction of bead geometry given by these models were also carried out. Graphic results display the effects of process parameter and interaction effects on bead geometry. Findings: The fitting and the prediction capabilities of interaction models are reliable than the linear and curlinear models and it was found that welding voltage, arc current, welding speed and 2-way interaction CTWD welding angle have the large significant effects on bead geometry. Research limitations/implications: The these models developed are extended to shielding gas composition, weld joint position, polarity and many other parameters which are not included in this research in order to establish a closed loop feedback control system to minimize possible errors from uncontrolled variations. Practical implications: The developed models apply real-time control for bead geometry in GMA welding process and perform the Design of Experiments (DOE) analysis steps in order to solve optimisation problems in GMA welding process. Originality/value: The interaction factors, welding voltage arc current, CTWD welding angle, also imposes a significant effect on bead geometry. With the experimental data of this study, the interaction models have a more reliable fitting and better predicting than that of linear and curvilinear models.

3

Predicting Lap-Joint bead geometry in GMA welding process

Thao D., Jeong J., Kim I., Kim J.

Archives of Materials Science and Engineering

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2008

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Vol. 32, nr 2

121-124

EN

Purpose: The prediction of the optimal bead geometry is an important aspect in robotic welding process. Therefore, the mathematical models that predict and control the bead geometry require to be developed. This paper focuses on investigation of the development of the simple and accuracy interaction model for prediction of bead geometry for lap joint in robotic Gas Metal Arc (GMA) welding process. Design/methodology/approach: The sequent experiment based on full factorial design has been conducted with two levels of five process parameters to obtain bead geometry using a GMA welding process. The analysis of variance (ANOVA) has efficiently been used for identifying the significance of main and interaction effects of process parameters. General linear model and regression analysis in SPSS has been employed as a guide to achieve the linear, curvilinear and interaction models. The fitting and the prediction of bead geometry given by these models were also carried out. Graphic results display the effects of process parameter and interaction effects on bead geometry. Findings: The fitting and the prediction capabilities of interaction models are reliable than the linear and curvilinear models. It was found that welding voltage, arc current, welding speed and 2-way interaction CTWD×welding angle have the large significant effects on bead geometry. Practical implications: The model should also cover a wide range of material thicknesses and be applicable for all welding position. For the automatic welding system, the data must be available in the form of mathematical equations. Originality/value: It has been realized that with the use of the developed algorithm, the prediction of optimal bead dimensions becomes much simpler to even a novice user who has no prior knowledge of the robotic GMA welding process and optimization techniques.

4

Modele interakcyjne i modele śledzące konstrukcji budynków

Krętowska J., Miedziałowski Cz.

Zeszyty Naukowe Politechniki Białostockiej. Budownictwo

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2001

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Z.21

179--189

PL

W pracy przedstawiono modele interakcyjne i tzw. modele śledzące (zmieniające się wraz ze zmianami w konstrukcji) wykorzystywane w analizie układu budowla - podłoże gruntowe. Zmiany zachodzące w okresie wznoszenia obiektu oraz przy degradacji, naprawie i rozbudowie konstrukcji budynków wpływają na zmiany schematów statycznych konstrukcji i zmiany konfiguracji układu. Ma to istotne znaczenie przy prawidłowym wyznaczaniu rozkładu sił wewnętrznych. Podano również różne sposoby modelowania interakcji budowla - podłoże gruntowe oraz sposób budowy obliczeniowych modeli śledzących i ich szybkiego rozwiązywania i analizy. Przykład obliczeniowy ilustruje opisywane zjawiska.

EN

The interaction's models and so called tracing models varying with alterations and changes in the structure in this case in the building - subsoil system have been presented in the paper. The above changes can take place while erection as well as during degradation, repair or expand of building structure. These alterations create changes of a statical scheme of system or material properties of indyvidual elements of structure. Correct distribution of internal forces in the structure requires taking into account collaboration of subsoil and structure in the analysis. The way of the description the soil - structure interaction models, the method of creation of the computational tracing models, the way how them resolve and analyse have been presented in the paper. The computational example concerning the presented problem has been also described in the paper.