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The paper presents results of investigations of compressive strength and shrinkage of concrete samples made on the basis of the Portland cement CEM I 32.5R, after 2, 7, 14, 28, 90, and 365 days of maturation in four different maturation conditions. It was shown that after 28 days the samples cured according to the standard in the cuvettes with water achieved the highest compressive strength, although the early-age compressive strengths after 7 and 14 days were lower than those for the samples cured in building film and in dry conditions. A determined correlation between the compressive strength and shrinkage of the concrete proves that wet curing also allows a total elimination of the shrinkage in the first 28 days. Along with the growth of the compressive strength, the drying shrinkage reduces. Obtained results confirmed that the best way of concrete curing, among the analyzed methods, from the point of view of both compressive strength and volume changes is the wet curing.
Olga Szlachetka; Joanna Witkowska-Dobrev; Marek Dohojda; Anna Cała. Influence of compressive strength and maturity conditions on shrinkage of ordinary concrete. Advances in Mechanical Engineering 2021, 13, 1 .
AMA StyleOlga Szlachetka, Joanna Witkowska-Dobrev, Marek Dohojda, Anna Cała. Influence of compressive strength and maturity conditions on shrinkage of ordinary concrete. Advances in Mechanical Engineering. 2021; 13 (6):1.
Chicago/Turabian StyleOlga Szlachetka; Joanna Witkowska-Dobrev; Marek Dohojda; Anna Cała. 2021. "Influence of compressive strength and maturity conditions on shrinkage of ordinary concrete." Advances in Mechanical Engineering 13, no. 6: 1.
Concrete is a highly alkaline material; therefore, the presence of organic acids (acetic, butyric, lactic) from agricultural sewage constitutes a threat to the concrete and the environment. The investigations were aimed at simulating the influence of highly concentrated organic acids on concrete elements of livestock buildings. Cubic samples 100 × 100 × 100 mm of the ordinary concrete were immersed in 10% acetic acid for 270 days. Then, the compressive strength and mass decrement of the samples were determined as well as using SEM images and a 3D-profilograph to profile the surface roughness and depth of changes evoked in the structure of the samples by penetrating acid. The results were compared with those for a control sample (not subjected to the effects of aggressive agents) as well as for samples placed in a neutral and alkaline environment. The compressive strength of the samples stored in the acidic environment was 22.23% lower than that of the control sample, whereas the compressive strength of those samples stored in an alkaline environment were 44.27% higher. Conclusions from these investigations can be of innovative importance in the preparation of environmental impact reports, which are necessary for obtaining permission for the construction and use of livestock buildings, and afterward in the reduction of the impact of these buildings on the environment and surface and underground water resources.
Joanna Witkowska-Dobrev; Olga Szlachetka; Marek Dohojda; Krzysztof Wiśniewski. Effect of Acetic Acid on Compressive Strength and Geometric Texture of the Surface of C20/25 Class Concrete. Sustainability 2021, 13, 5136 .
AMA StyleJoanna Witkowska-Dobrev, Olga Szlachetka, Marek Dohojda, Krzysztof Wiśniewski. Effect of Acetic Acid on Compressive Strength and Geometric Texture of the Surface of C20/25 Class Concrete. Sustainability. 2021; 13 (9):5136.
Chicago/Turabian StyleJoanna Witkowska-Dobrev; Olga Szlachetka; Marek Dohojda; Krzysztof Wiśniewski. 2021. "Effect of Acetic Acid on Compressive Strength and Geometric Texture of the Surface of C20/25 Class Concrete." Sustainability 13, no. 9: 5136.
The paper consists of the discussion of issues related to the durability of foundations of extra high voltage (EHV) power line poles and possibilities of their renovation. The research part is the diagnostics of selected foundations of the EHV line poles (400 kV) Wielopole–Noszowice. During the on-site inspection, it was found that there are chipping and small surface defects, and in some cases losses of the reinforcement cover without visible pits. Based on the degree of damage, the scope of non-structural repairs and anti-corrosive protection was determined, presenting the next stages of their implementation.
Joanna Witkowska-Dobrev; Anna Brzezińska; Olga Szlachetka. Najczęściej występujące uszkodzenia fundamentów słupów linii elektroenergetycznych najwyższych napięć i sposoby ich napraw. Przegląd Naukowy Inżynieria i Kształtowanie Środowiska 2020, 29, 461 -473.
AMA StyleJoanna Witkowska-Dobrev, Anna Brzezińska, Olga Szlachetka. Najczęściej występujące uszkodzenia fundamentów słupów linii elektroenergetycznych najwyższych napięć i sposoby ich napraw. Przegląd Naukowy Inżynieria i Kształtowanie Środowiska. 2020; 29 (4):461-473.
Chicago/Turabian StyleJoanna Witkowska-Dobrev; Anna Brzezińska; Olga Szlachetka. 2020. "Najczęściej występujące uszkodzenia fundamentów słupów linii elektroenergetycznych najwyższych napięć i sposoby ich napraw." Przegląd Naukowy Inżynieria i Kształtowanie Środowiska 29, no. 4: 461-473.
This paper aims to present the results of compressive strength tests of concrete specimens, prepared according to two recipes, after 2, 7 and 28 days of maturing in four different environments. The concrete specimens had the same w/c ratio, the same amount of aggregate of particular fractions, the addition of a superplasticizer, but they differed in the cement type. In one recipe, the Portland cement CEM I 32.5R was used, in the other – pozzolanic ash cement CEM IV/B(V) 32.5R-LH/NA. Concrete specimens with dimensions of 100 x 100 x 100 mm made according to both recipes were placed in individual ripening environments: in cuvettes with water, soaked and wrapped with construction foil, left in room conditions in the laboratory, placed outside the laboratory and being exposed to the atmospheric conditions. The obtained compressive strength results confirmed that the best way of curing concrete is the wet cure (in cuvettes with water). It has been proven that the choice of proper curing method is key in terms of compressive strength.
Joanna Witkowska-Dobrev; Olga Szlachetka; Paulina Spiek. Impact of maturation conditions for concrete on its compressive strength. Budownictwo i Architektura 2020, 19, 101 -110.
AMA StyleJoanna Witkowska-Dobrev, Olga Szlachetka, Paulina Spiek. Impact of maturation conditions for concrete on its compressive strength. Budownictwo i Architektura. 2020; 19 (2):101-110.
Chicago/Turabian StyleJoanna Witkowska-Dobrev; Olga Szlachetka; Paulina Spiek. 2020. "Impact of maturation conditions for concrete on its compressive strength." Budownictwo i Architektura 19, no. 2: 101-110.
The Rayleigh’s method can be used to determine the first natural frequency of beams with variable cross-section. The authors analyse multi-segment simply supported beams, symmetrical with respect to their midpoint, having a constant width and variable height. The beams consist generally of five segments. It has been assumed that the neutral bar axis deflected during vibrations has a shape of a beam deflected by a static uniform load. The calculations were made in Mathematica environment and their results are very close to those obtained with FEM.
Marek Chalecki; Jacek Jaworski; Olga Szlachetka. First natural frequency of multi-segment floor joists with variable cross section. Przegląd Naukowy Inżynieria i Kształtowanie Środowiska 2019, 28, 526 -538.
AMA StyleMarek Chalecki, Jacek Jaworski, Olga Szlachetka. First natural frequency of multi-segment floor joists with variable cross section. Przegląd Naukowy Inżynieria i Kształtowanie Środowiska. 2019; 28 (4):526-538.
Chicago/Turabian StyleMarek Chalecki; Jacek Jaworski; Olga Szlachetka. 2019. "First natural frequency of multi-segment floor joists with variable cross section." Przegląd Naukowy Inżynieria i Kształtowanie Środowiska 28, no. 4: 526-538.
In calculations of first natural frequency of transversal vibrations of clamped-free bars with variable cross section, one can use an energetic method. The aim of this paper is an analysis of vibrations of solid and hollow slender posts having the shape of solid of revolution with the generatrix described by an exponential curve. The authors used the Rayleigh’s method with the assumption that the shape of the post axis deflected during vibration is the same as a shape of the axis of a beam deflected by a uniform continuous static load. It was also assumed that the bars are made of an elastic and continuously distributed material what required numerous integrations of complicated expressions, therefore the calculations were carried out using the MATHEMATICA environment. Apart of the elastic energy of the bar, the authors considered also the potential energy connected to changes of location of the gravity center of elementary material slices during the post axis deflection. It was considered both the kinetic energy resulting from the replacement of the material slices perpendicular to the post axis as well as the energy connected to their rotation. The obtained results are very close to those obtained in FEM.
Olga Szlachetka; Jacek Jaworski; Marek Chalecki. Free Vibration of Cantilever Bars Having a Shape of Solid and Hollow Curvilinear Truncated Cone. Springer Texts in Business and Economics 2018, 461 -472.
AMA StyleOlga Szlachetka, Jacek Jaworski, Marek Chalecki. Free Vibration of Cantilever Bars Having a Shape of Solid and Hollow Curvilinear Truncated Cone. Springer Texts in Business and Economics. 2018; ():461-472.
Chicago/Turabian StyleOlga Szlachetka; Jacek Jaworski; Marek Chalecki. 2018. "Free Vibration of Cantilever Bars Having a Shape of Solid and Hollow Curvilinear Truncated Cone." Springer Texts in Business and Economics , no. : 461-472.
The present study aims to analyse a two-dimensional problem of displacements in theory of thermal stresses for multicomponent, multi-layered periodic composites. The model equations are obtained within the framework of the tolerance modelling procedure. These equations allow to determine the distribution of displacements caused by the temperature field in the theory of thermal stresses. The paper presents an example of a solution of a boundary value problem.
Vazgen Bagdasaryan; Monika Wągrowska; Olga Szlachetka. Displacements Caused by the Temperature in Multicomponent, Multi-Layered Periodic Material Structures. Mechanics and Mechanical Engineering 2018, 22, 809 -820.
AMA StyleVazgen Bagdasaryan, Monika Wągrowska, Olga Szlachetka. Displacements Caused by the Temperature in Multicomponent, Multi-Layered Periodic Material Structures. Mechanics and Mechanical Engineering. 2018; 22 (3):809-820.
Chicago/Turabian StyleVazgen Bagdasaryan; Monika Wągrowska; Olga Szlachetka. 2018. "Displacements Caused by the Temperature in Multicomponent, Multi-Layered Periodic Material Structures." Mechanics and Mechanical Engineering 22, no. 3: 809-820.
Vazgen Bagdasaryan; Marek Chalecki; Michał Gierasimiuk; Jacek Jaworski; Olga Szlachetka. First natural transverse frequency of truncated cone and wedge beams. ACTA SCIENTIARUM POLONORUM - Architectura Budownictwo 2018, 17, 3 -12.
AMA StyleVazgen Bagdasaryan, Marek Chalecki, Michał Gierasimiuk, Jacek Jaworski, Olga Szlachetka. First natural transverse frequency of truncated cone and wedge beams. ACTA SCIENTIARUM POLONORUM - Architectura Budownictwo. 2018; 17 (1):3-12.
Chicago/Turabian StyleVazgen Bagdasaryan; Marek Chalecki; Michał Gierasimiuk; Jacek Jaworski; Olga Szlachetka. 2018. "First natural transverse frequency of truncated cone and wedge beams." ACTA SCIENTIARUM POLONORUM - Architectura Budownictwo 17, no. 1: 3-12.
The object of the analysis is a two-dimensional elastostatic problem for multicomponent, multilayered periodic composites. The equations of equilibrium for this composite are obtained within the framework of tolerance modelling procedure. The paper presents two examples of solutions of boundary value problems.
Monika Wągrowska; Vazgen Bagdasaryan; Olga Szlachetka. Elastostatic problems in multicomponent, multilayered periodic composites. Przegląd Naukowy Inżynieria i Kształtowanie Środowiska 2018, 27, 9 -18.
AMA StyleMonika Wągrowska, Vazgen Bagdasaryan, Olga Szlachetka. Elastostatic problems in multicomponent, multilayered periodic composites. Przegląd Naukowy Inżynieria i Kształtowanie Środowiska. 2018; 27 (1):9-18.
Chicago/Turabian StyleMonika Wągrowska; Vazgen Bagdasaryan; Olga Szlachetka. 2018. "Elastostatic problems in multicomponent, multilayered periodic composites." Przegląd Naukowy Inżynieria i Kształtowanie Środowiska 27, no. 1: 9-18.
Olga Szlachetka; Wydział Budownictwa i Inżynierii Środowiska SGGW w Warszawie; Marek Chalecki; Jacek Jaworski. Analysis of free vibrations of cantilever bars with parabolically variable cross-sections using the Rayleigh’s method. ACTA SCIENTIARUM POLONORUM - Architectura Budownictwo 2017, 16, 5 -14.
AMA StyleOlga Szlachetka, Wydział Budownictwa i Inżynierii Środowiska SGGW w Warszawie, Marek Chalecki, Jacek Jaworski. Analysis of free vibrations of cantilever bars with parabolically variable cross-sections using the Rayleigh’s method. ACTA SCIENTIARUM POLONORUM - Architectura Budownictwo. 2017; 16 (4):5-14.
Chicago/Turabian StyleOlga Szlachetka; Wydział Budownictwa i Inżynierii Środowiska SGGW w Warszawie; Marek Chalecki; Jacek Jaworski. 2017. "Analysis of free vibrations of cantilever bars with parabolically variable cross-sections using the Rayleigh’s method." ACTA SCIENTIARUM POLONORUM - Architectura Budownictwo 16, no. 4: 5-14.
Jacek Jaworski; Olga Szlachetka. Free Vibrations of Cantilever Bars with Linear and Nonlinear Variable Cross-Section. The interdisciplinary journal of Discontinuity, Nonlinearity and Complexity 2017, 6, 489 -501.
AMA StyleJacek Jaworski, Olga Szlachetka. Free Vibrations of Cantilever Bars with Linear and Nonlinear Variable Cross-Section. The interdisciplinary journal of Discontinuity, Nonlinearity and Complexity. 2017; 6 (4):489-501.
Chicago/Turabian StyleJacek Jaworski; Olga Szlachetka. 2017. "Free Vibrations of Cantilever Bars with Linear and Nonlinear Variable Cross-Section." The interdisciplinary journal of Discontinuity, Nonlinearity and Complexity 6, no. 4: 489-501.
Olga Szlachetka; Marek Dohojda; Małgorzata Lusawa; Ryszard Mazurczuk. Wytrzymałość zmęczeniowa prętów żebrowanych ze stali B500SP. ACTA SCIENTIARUM POLONORUM - Architectura Budownictwo 2017, 16, 3 -10.
AMA StyleOlga Szlachetka, Marek Dohojda, Małgorzata Lusawa, Ryszard Mazurczuk. Wytrzymałość zmęczeniowa prętów żebrowanych ze stali B500SP. ACTA SCIENTIARUM POLONORUM - Architectura Budownictwo. 2017; 16 (1):3-10.
Chicago/Turabian StyleOlga Szlachetka; Marek Dohojda; Małgorzata Lusawa; Ryszard Mazurczuk. 2017. "Wytrzymałość zmęczeniowa prętów żebrowanych ze stali B500SP." ACTA SCIENTIARUM POLONORUM - Architectura Budownictwo 16, no. 1: 3-10.
The object of analysis is a heat conduction problem within the framework of tolerance modelling in multicomponent, multilayered periodic composites. The proposed model equations describe heat conduction in the discussed laminates by means of partial differential equations with constant coefficients. This paper describes the one-dimensional, stationary problems of heat conduction in direction perpendicular to layers.
Monika Wągrowska; Olga Szlachetka. Distribution of Temperature in Multicomponent Multilayered Composites. Continuous Media with Microstructure 2 2016, 199 -214.
AMA StyleMonika Wągrowska, Olga Szlachetka. Distribution of Temperature in Multicomponent Multilayered Composites. Continuous Media with Microstructure 2. 2016; ():199-214.
Chicago/Turabian StyleMonika Wągrowska; Olga Szlachetka. 2016. "Distribution of Temperature in Multicomponent Multilayered Composites." Continuous Media with Microstructure 2 , no. : 199-214.
Przedmiotem rozważań jest jednowymiarowe, stacjonarne zagadnienie przewodnictwa ciepła w kierunku prostopadłym do uwarstwienia w wieloskładnikowym, wielowarstwowym kompozycie o poprzecznej gradacji właściwości efektywnych. W celu wyznaczenia rozkładu temperatury wykorzystano wariant asymptotyczny modelowania tolerancyjnego. Obliczono wartości efektywnego współczynnika przewodzenia ciepła oraz wyznaczono rozkłady temperatury dla pewnych szczególnych przypadków
Olga Szlachetka; Monika Wągrowska. ROZKŁAD TEMPERATURY W WIELOSKŁADNIKOWYM WIELOWARSTWOWYM KOMPOZYCIE Z POPRZECZNĄ GRADACJĄ WŁAŚCIWOŚCI EFEKTYWNYCH. Journal of Civil Engineering, Environment and Architecture 2016, 1 .
AMA StyleOlga Szlachetka, Monika Wągrowska. ROZKŁAD TEMPERATURY W WIELOSKŁADNIKOWYM WIELOWARSTWOWYM KOMPOZYCIE Z POPRZECZNĄ GRADACJĄ WŁAŚCIWOŚCI EFEKTYWNYCH. Journal of Civil Engineering, Environment and Architecture. 2016; ():1.
Chicago/Turabian StyleOlga Szlachetka; Monika Wągrowska. 2016. "ROZKŁAD TEMPERATURY W WIELOSKŁADNIKOWYM WIELOWARSTWOWYM KOMPOZYCIE Z POPRZECZNĄ GRADACJĄ WŁAŚCIWOŚCI EFEKTYWNYCH." Journal of Civil Engineering, Environment and Architecture , no. : 1.
Jacek Jaworski; Olga Szlachetka; Luz Antonio Aguilera -Cortés. Zastosowanie metody Rayleigh’a do obliczenia pierwszej częstości drgań własnych słupów wspornikowych o zmiennym przekroju poprzecznym. Journal of Civil Engineering, Environment and Architecture 2015, XXXII, 185 -194.
AMA StyleJacek Jaworski, Olga Szlachetka, Luz Antonio Aguilera -Cortés. Zastosowanie metody Rayleigh’a do obliczenia pierwszej częstości drgań własnych słupów wspornikowych o zmiennym przekroju poprzecznym. Journal of Civil Engineering, Environment and Architecture. 2015; XXXII (3/II/2015):185-194.
Chicago/Turabian StyleJacek Jaworski; Olga Szlachetka; Luz Antonio Aguilera -Cortés. 2015. "Zastosowanie metody Rayleigh’a do obliczenia pierwszej częstości drgań własnych słupów wspornikowych o zmiennym przekroju poprzecznym." Journal of Civil Engineering, Environment and Architecture XXXII, no. 3/II/2015: 185-194.
The object of analysis is a heat conduction problem within the framework of tolerance modelling in laminated media with a functional gradation of effective properties. In contrast to the known asymptotic models (based on the homogenization technique), the characteristic feature of the tolerance model equations is that they make it possible to analyze the effect of the microstructure size on the overall behavior of the laminate. The proposed model equations describe heat conduction in laminates by mean of partial differential equations with smooth and slowly varying functions. This paper describes a certain extension of the unified tolerance modelling procedure, which makes it possible to analyze specific problems of heat conduction in laminates with a transversal gradation of effective properties.
C. Wozniak; M. Wagrowska; O. Szlachetka. On the tolerance modelling of heat conduction in functionally graded laminated media. Journal of Applied Mechanics and Technical Physics 2015, 56, 274 -281.
AMA StyleC. Wozniak, M. Wagrowska, O. Szlachetka. On the tolerance modelling of heat conduction in functionally graded laminated media. Journal of Applied Mechanics and Technical Physics. 2015; 56 (2):274-281.
Chicago/Turabian StyleC. Wozniak; M. Wagrowska; O. Szlachetka. 2015. "On the tolerance modelling of heat conduction in functionally graded laminated media." Journal of Applied Mechanics and Technical Physics 56, no. 2: 274-281.
Jacek Jaworski; Olga Szlachetka. Free vibration of truncated-cone columns. Journal of Civil Engineering, Environment and Architecture 2014, XXXI, 33 -42.
AMA StyleJacek Jaworski, Olga Szlachetka. Free vibration of truncated-cone columns. Journal of Civil Engineering, Environment and Architecture. 2014; XXXI (61 (2/14)):33-42.
Chicago/Turabian StyleJacek Jaworski; Olga Szlachetka. 2014. "Free vibration of truncated-cone columns." Journal of Civil Engineering, Environment and Architecture XXXI, no. 61 (2/14): 33-42.
The aim of the contribution is to formulate an asymptotic model of heat conduction for functionally graded two component laminate reinforced by periodically spaced micro inclusions. (© 2012 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Monika Wagrowska; Czesław Woźniak; Olga Szlachetka. A model of the heat conduction for functionally graded laminate with uniformly distributed micro inclusions. PAMM 2012, 12, 413 -414.
AMA StyleMonika Wagrowska, Czesław Woźniak, Olga Szlachetka. A model of the heat conduction for functionally graded laminate with uniformly distributed micro inclusions. PAMM. 2012; 12 (1):413-414.
Chicago/Turabian StyleMonika Wagrowska; Czesław Woźniak; Olga Szlachetka. 2012. "A model of the heat conduction for functionally graded laminate with uniformly distributed micro inclusions." PAMM 12, no. 1: 413-414.
Olga Szlachetka; Monika Wagrowska; Joanna Witkowska-Dobrev; Czeslaw Wozniak; Monika W±Growska; Czes³Aw Wo¼Niak. On the mass discretization approach to elastodynamics of periodically stratified composites. Scientific Research of the Institute of Mathematics and Computer Science 2012, 11, 143 -150.
AMA StyleOlga Szlachetka, Monika Wagrowska, Joanna Witkowska-Dobrev, Czeslaw Wozniak, Monika W±Growska, Czes³Aw Wo¼Niak. On the mass discretization approach to elastodynamics of periodically stratified composites. Scientific Research of the Institute of Mathematics and Computer Science. 2012; 11 (4):143-150.
Chicago/Turabian StyleOlga Szlachetka; Monika Wagrowska; Joanna Witkowska-Dobrev; Czeslaw Wozniak; Monika W±Growska; Czes³Aw Wo¼Niak. 2012. "On the mass discretization approach to elastodynamics of periodically stratified composites." Scientific Research of the Institute of Mathematics and Computer Science 11, no. 4: 143-150.
The paper presents a new method of modelling for certain microlayered heat conductors. So far the main attention related to the modelling of composite materials with deterministic structure was mainly restricted to the periodic composites (Bensoussan, Lions, and Papanicolaou [1]). The main future of the presented approach is that it can be also applied to the class with a non periodic structure. These structures can by referred to as functionally graded in the direction normal to the interfaces between layers. At the same time the non‐homogenous material structure of the composite is slowly varying in this direction. That is why the obtained model equations have functionally but slowly varying coefficients. Moreover, this equations can by applied for designing functionally graded heat conductors with given a priori class of temperature fields.
C. Woźniak; M. Wa̧growska; O. Szlachetka. Asymptotic modelling and design of some microlayered functionally graded heat conductors. ZAMM - Journal of Applied Mathematics and Mechanics / Zeitschrift für Angewandte Mathematik und Mechanik 2012, 92, 841 -848.
AMA StyleC. Woźniak, M. Wa̧growska, O. Szlachetka. Asymptotic modelling and design of some microlayered functionally graded heat conductors. ZAMM - Journal of Applied Mathematics and Mechanics / Zeitschrift für Angewandte Mathematik und Mechanik. 2012; 92 (10):841-848.
Chicago/Turabian StyleC. Woźniak; M. Wa̧growska; O. Szlachetka. 2012. "Asymptotic modelling and design of some microlayered functionally graded heat conductors." ZAMM - Journal of Applied Mathematics and Mechanics / Zeitschrift für Angewandte Mathematik und Mechanik 92, no. 10: 841-848.