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1

Wykorzystanie narzędzi BIM w projektowaniu kładki dla pieszych z modyfikowanego drewna o zwiększonej wytrzymałości

Pradelok Stefan, Piotrowski Krzysztof, Cesarz-Andraczke Katarzyna, Sakiewicz Piotr, Brzezowski Dawid, Korus Kamil, Nowak Artur, Łanuszewski Jacek, Opara Piotr

Materiały Budowlane

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2019

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nr 9

68--70

PL

W artykule opisano możliwości wykorzystania narzędzi BIM w procesie projektowania obiektów inżynierskich na przykładzie kładki dla pieszych z drewna modyfikowanego. Narzędzia BIM pozwalają na usprawnienie działań projektowych, zwłaszcza przez algorytmy parametryzacji geometrii. Obecnie badane procesy funkcjonalizacji drewna pozwalają na poprawę jego właściwości mechanicznych, czyniąc go konkurencyjnym materiałem, szczególnie biorąc pod uwagę aspekty ekologiczne.

EN

The article describes capabilities of using BIM tools in the bridges design process based on pedestrian bridge of modified wood. BIM tools allow to improve designing activities, especially through geometry parametrization algorithms. The processes of wood functionalization, which are currently being researched, allow improving it's mechanical properties, what makes wood competitive material, especially considering ecological aspects.

2

Composite materials for warship constructions

Kyzioł Lesław

Journal of KONES

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2019

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Vol. 26, No. 4

135--140

EN

The article presents the basic properties of composite materials used for the construction of special ships. Static and dynamic characteristics of materials such as wood and polyester-glass composites are presented. Noteworthy are materials such as surface modified wood and polyester-glass composites with the addition of recyclate. Composite materials are widely used materials for the construction of non-magnetic warships. The article describes the properties of surface modified wood with polymethyl methacrylate and a polyester-glass composite with the addition of recyclate. The recyclate is fragmented, milled polyester-glass scrap. The content of the recyclate greatly affects the mechanical properties of the composite. The properties of the composite with the addition of recyclate depend on the recyclate content as well as the production technology and size of the recycled granulates. The test results showed that the increase in the recycled content causes a decrease in the mechanical properties of the composite. However, it should be remembered that these materials originated from waste, waste that is not subject to self-degradation, which have a very negative impact on the natural environment. At present, where there is a very large pollution of the natural environment, the processing and management of huge amounts of composite waste is an essential goal. A significant amount of recyclate significantly reduces the mechanical properties of the composite; however, the same large amount of recycled material has been transformed and used. The manufactured material and its structural elements are still non-magnetic structures and can be used on a less loaded element. The choice of material for the construction of special ships elements is determined not only by its properties but also by knowledge, experience, method of processing, economic and technical risk.

3

Domingos I., Ferreira J., Cruz-Lopes L., Esteves B.

Drewno : prace naukowe, doniesienia, komunikaty

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2018

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vol. 61, nr 202

69--80

EN

A study was made of water-related properties of Pinus pinaster wood impregnated with paraffin or modified by heat treatment or furfurylation. Treated woods were submerged in water for periods ranging from 2 to 1680 hours. Water absorption, swelling, and dimensional stability in the radial and tangential directions – expressed as Anti-Shrinking Efficiency (ASE) – were determined. Water absorption increased with time, reaching approximately 140% after 1680 h for untreated and heat-treated wood, and 60% for paraffinated and furfurylated wood. The rate of swelling differed between the first hours of soaking and after prolonged immersion. The final swelling was approximately 9% and 6% for untreated pine, 8% and 4% for paraffinated pine, 5.5% and 3% for heat-treated pine and 2.5% and 1% for furfurylated pine (in the tangential and radial directions respectively). At the end of the soaking test, furfurylated pine had the best ASE of approximately 80% and 70% in the tangential and radial directions respectively, followed by heat-treated pine with 44% and 34%, and paraffinated wood with 35% and 13%.

4

Determination of the material constants of composite materials on the example of modified wood

Kyzioł L.

Journal of KONES

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2017

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Vol. 24, No. 2

133--140

EN

Homogenization is the transition from the level of microscopic heterogeneity to a homogeneous macroscopic level. The analysis of the value of equivalent parameters and their variability requires prior determination of the influence of microstructure on the values of these parameters [15]. Wood is a composite material and has a layered structure in the form of alternate layers of soft and hard wood. One of the main issues was the determination of constants materials of individual layers of natural wood and modified and then equivalent material constants of natural and modified wood. The material constants of single layers and the material constants of composite were determined on the basis of experimental studies. For this purpose, a homogenization method has been used to determine equivalent material constants on the basis of material constants of single layers of soft and hard wood [1, 2, 14]. A representative cell consisting of a softwood and hardwood layer has been isolated from the sample-measuring portion. On the basis of this cell have been developed mathematical model of equivalent material constants. A sample consisting of two layers was subjected to an even stretch in the direction of the axes x1, x2, x3. The equivalent material constants have been defined by using equilibrium conditions, geometric conditions, and Hooke’s generalized law. Each wood component on the micro-level is homogeneous, continuous with its constitutive equation, conservation laws, and boundary conditions at the boundary of the separation of components. The equivalent material constants of natural and modified wood have been determined using the homogenization method [12, 13]. The results obtained from the research and the results obtained from the calculations are very similar.

5

Description of strength of wood composite in compound state of load

Kyzioł L.

Journal of KONES

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2017

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Vol. 24, No. 3

161--165

EN

All constructions are subject to the most compound loads and therefore a suitable effort hypothesis should be used for their calculation. For anisotropic materials, a hypothesis should be used to describe the properties of such materials. In the work have been shown the strength of the layers composite on the example of construction wood in a compound stress state. Wood composite is an orthotropic material. Wood is composed of alternating layers of soft wood and hard wood. Single layers are monotropic material. The use of a stress hypothesis, which describes the strength of an orthotropic material, requires will make an investigation. Studies is purposed to determine the tensile strength along and across the fibres. The compressive strengths along and across the fibres and the shear strength. Particularly the determination of shear strength requires special tooling so that in the case of flat samples in the measuring part it is possible to determine the shear stresses. Therefore, a research stand was designed and constructed. Known stress hypotheses for anisotropic materials have been analysed. The analysis showed that the strength of the wood composite could be described by the Tai-Wu stress hypothesis. Based on the results of the research, numerical calculations were performed. Calculations allowed determining the distribution of stresses in the sample measuring part. The results tests and numerical calculations have shown that obtaining a homogeneous stress (shear) condition for anisotropic materials is very difficult. Wood belongs to materials whose mechanical properties depend on many parameters, so the description of the effort of this material is a compound issue. Studies have shown that wood reinforcement by polymer saturation is best suited to the compressed loaded structures.

6

Shear stress in measuring section of the sample with modified wood

Kyzioł L.

Journal of KONES

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2016

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Vol. 23, No. 1

193--198

EN

The shear strength of anisotropic materials is carried out on the special samples and on the appropriate instrumentation. Research conducted to obtain a homogenous state of the shear stress in the plane sample is difficult, and involve numerous occurrence of additional stress. Therefore, it is difficult to determine the shear strength. The wood composites are classified as orthotropic materials. In addition, are composed of the layers early wood and latewood. The layers have different thicknesses and exhibit different strength properties. The principal method for determining the shear stress is the trial of twisting of thin-walled tubes. Production of the pipe samples from the wood to determine the shear stress is impossible, due to annual rings. Beginning of destruction of samples under load was registered by a prototype device. This device makes the realization of plane state of stress in the sample possible. The position of the axis of the sample relative to the direction of the load can be varied. Such configuration axle of the sample to the loading direction, allows to perform, also stretching or compression besides to shear. The tests were performed for the natural wood and surface modified wood. The paper presents an original method and device designed to determine the shear strength of anisotropic materials on the example of natural wood and a surface modified wood.

7

Możliwości zastosowania drewna modyfikowanego na okręty przeciwminowe

Kyzioł L.

Logistyka

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2015

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nr 3

2740--2749, CD 1

PL

Przedstawiono podstawowe materiały amagnetyczne stosowane do budowy okrętów zwalczania min. Dokonano charakterystyki podstawowych materiałów takich jak drewno, kompozyty poliestrowo-szklane oraz stal niemagnetyczną. Materiały te są powszechnie stosowane do budowy jednostek amagnetycznych. Na uwagę zasługuje drewno modyfikowane, charakteryzujące się znacznie wyższymi właściwościami mechanicznymi od drewna naturalnego a tylko niewiele wyższymi kosztami. O wyborze materiału do budowy jednostek amagnetycznych decyduję nie tylko jego właściwości ale wiedza, doświadczenie, sposób przetwarzania, ryzyko ekonomiczne oraz techniczne.

EN

In the article has been presented non-magnetic materials used for the minecountermeasure vessels. The characteristics of the materials are presented, such as wood, composites of polyester-glass and non-magnetic stainless steel. These materials are commonly used in the minecountermeasure vessels. Modified wood deserves attention because it is characterized by a much higher mechanical properties of natural wood. Modified wood costs are a little higher than natural wood. The choice of material for the minecountermeasure vessels is dependent on the properties of the material of knowledge, experience, processing of material, economic, and technical risk.

8

Content of respirable and inhalable fractions in dust created at sawing beech wood and its modifications

Hlásková L., Rogoziński T., Dolny S., Kopecký Z., Jedinák M.

Drewno : prace naukowe, doniesienia, komunikaty

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2015

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vol. 58, nr 194

135--146

EN

This paper presents the results of the granulometric analysis of sawdust, created during the sawing of modified and unmodified beech wood with a circular saw. The aim of this work was to analyze the effect of the treatment of beech wood (Fagus sylvatica L.) on the content of respirable and inhalable particles in sawdust generated during the sawing process using a modern circular saw. Different methods of particle-size determination were used. The results obtained from the sieve analysis prove that the sawdust created during the cutting of DMDHEU was finer than the sawdust from native beech and other modified materials. It was also discovered that the dust created during the cutting of Bendywood was finer than when machining native beech and Lignamon. There was an increase in the share of fine fraction in the range of granularity x < 100 μm at the expense of the fraction x = 0.25–1 mm. The properties of Lignamon are primarily based on the properties of raw wood material, therefore this modified material had a similar cumulative particle-size distribution to the native beech dust.

9

Propozycja zastosowania drewna modyfikowanego na konstrukcje morskie

Kyzioł L.

Zeszyty Naukowe Akademii Morskiej w Gdyni

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2014

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nr 83

121--129

PL

Przedstawiono przykłady uszkodzeń kadłubów łodzi rybackich i jachtów wykonanych z drewna naturalnego. Najczęstszą przyczyną uszkodzeń poszycia tych jednostek są pęknięcia, spowodowane podatnością drewna do nasiąkania wodą, a następnie wysychania. Drewno jako materiał porowaty jest podatne na wilgoć. Naturalne drewno po wypełnieniu porów wodą obniża swoje właściwości wytrzymałościowe, twardość, ścieralność oraz udarność. Ponadto łączniki, jakimi są wkręty stalowe, w obecności wody korodują, doprowadzając do korozji drewna. Otwory w drewnie pod wkręty stanowią karby, które przyczyniają się do powstania pęknięć, w związku z czym w miejsce drewna naturalnego zaproponowano drewno modyfikowane powierzchniowo polimerem metakrylanem metylu. Materiał ten zmniejsza naturalne wady drewna, tworząc zwartą i twardą strukturę o wysokich właściwościach wytrzymałościowych. Zaprezentowano charakterystyki wytrzymałościowe. Ponad 5-krotnie mniejsza podatność do nasiąkania drewna modyfikowanego w stosunku do drewna naturalnego predysponuje ten materiał na konstrukcje morskie.

EN

This article presents the examples of damage the hulls of fishing boats and yachts made of natural wood. The main cause of damage hull of these boats are cracks. The cracks are caused by the flexibility of the wood for absorption the water. Wood as the porous material is vulnerable to moisture. Natural wood after filling the pores with water lowers its mechanical properties, hardness, grindability and the impact strength. Connectors, which are steel screws corrode in the presence of water leading to the corrosion of wood. The holes for screws in the wood are notches, which contribute to the formation of cracks. Therefore, natural wood can be to replace the surface modified wood. Wood modified eliminates the disadvantages of natural wood. The structure is hard with high strength properties. In the article were presented the characteristics of strength. Wood modified more than 5 times less absorb water than natural wood. Therefore material may be used for marine structures.

10

Analiza rozkładu naprężeń w przekroju konstrukcji z materiału anizotropowego

Kyzioł L.

Zeszyty Naukowe Akademii Morskiej w Gdyni

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2014

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nr 83

130--140

PL

Wytrzymałość na ścinanie określa się na podstawie badań przeprowadzonych na próbce Iosipescu. Zniszczenie próbki Iosipescu można osiągnąć w stanie jednorodnego naprężenia, chociaż obecność niepożądanego naprężenia poprzecznego komplikuje interpretację wytrzymałości na ścinanie. Wstępne badania drewna naturalnego i modyfikowanego na typowej próbce Iosipescu wykazały, że nie uzyskuje się poprawnych wyników. Przy próbie ścinania typowej próbki Iosipescu w dnie karbu występują nie tylko naprężenia styczne. Przy poprzecznym obciążeniu próbek występuje zginanie i powstają naprężenia normalne od momentu zginającego. Włókna drewna odkształcają się. Wiedza i doświadczenie pozwoliły na przyjęcie próbki o odpowiedniej geometrii. Badania zmodyfikowanej próbki Iosipescu przeprowadzono na zaprojektowanym i prototypowym przyrządzie. Przyrząd ten umożliwił przeprowadzenie badań próbek z kompozytu drewna w złożonych stanach obciążeń.

EN

Shear strength is determined based on research conducted on a sample Iosipescu. The destruction of Iosipescu sample can be achieved in a homogeneous stress state, although the presence of unwanted the transverse tension complicates the interpretation of shear strength. Studies of natural wood and modified for typical Iosipescu sample showed that not obtained the correct results. Study the Iosipescu typical sample showed that in the bottom of the notch are not only shear stress. During transverse load the samples there is a bending and normal stresses arise from the bending moment. Wood fibers are deformed. Knowledge and experience led to the adoption adequate geometry the sample. The tests of Iosipescu modified sample were performed on designed and a prototype instrument. This instrument has enabled to carry out tests on samples from composite wood in complex load conditions.

11

Method of determining the structural parameters of wood-polymer composite

Kyzioł L., Murawski L.

Journal of KONES

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2014

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Vol. 21, No. 2

177--184

EN

A composite material consisting of woody skeleton and polymerized methacrylate has been developed and characterized. This paper presents an experimental program and the results concerning mechanical properties and strength of wood modified with polymerized methacrylate. In the article, there are examples of structural elements made of natural wood. Wood is a composite consisting of the layers of soft and hard wood. Wood is a composite and porous material. The porosity, which is a serious defect of wood, may be simultaneously its advantage. Wood saturation with different impregnates to minimize its disadvantages. If the wood pores will fill the monomer there is obtained the wood polymer composite. This composite is classified as of fiber composites. Such composite is effectively protected against degradation; it is durable in use, and show an improvement in mechanical properties. Design constructions of surface modified wood require the determination of fundamental material constants. Therefore, for the determination of these parameters is very important obtaining the appropriate research material. The surface impregnation of wood allows obtaining strength characteristics in a function of polymer content. This allows to model it's, and then design and perform specific ship structures. In the wood, there are three directions in relation to the annual rings. Wood properties, especially mechanical properties, are different in the selected directions. For the computation takes the orthogonal anisotropy in which there are three mutually orthogonal planes of symmetry, for which there is symmetry properties of the wood.

12

Fatigue strength of wood polymer composite

Kyzioł L.

Journal of KONES

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2014

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Vol. 21, No. 1

139--146

EN

This paper presents the results of a study on the fatigue strength in pendulum bending natural and modified pinewood. The contents of polymethyl methacrylate (PMMA) were determined in wood-polymer for mechanical and rheological properties. The study of the bending fatigue strength and creep was realized on suitably prepared samples and research positions. Test results were documented in the form of charts and scraps. Differences in the decay of the natural and modified wood samples were observed after the attempt of the fatigue strength. The various mechanical properties of the sapwood, hardwood, and the polymer, influence on the stiffness of the individual components and consequently the whole composite. The process of fatigue degrades the structure of natural wood and wood polymer composite, the result is a gradual reduction of its stiffness. The Study of the creep behaviour was realized in stress in the sample of the level of 30% of the tensile strength. The samples were loaded longitudinally and transversely to the direction of the fibres. Significant differences of composite deformations were observed both as for the direction of the loaded fibres as well as the natural and modified wood. The character of changes in the fatigue strength and creep behaviour of the studied materials is implies to the influence of the polymer content on mechanical properties of modified wood. The tests carried out on account of the possibility of using wood polymer composite in sea constructions. Research carried out in connection with the possibility of the use of wood polymer composite marine construction. Modified wood can be used for keel blocks, decks, fender beam, bearings cantilevered shaft lines and the construction of yachts.

13

Modified wood (lignomer) -- a promising material for shipbuilding

Kyzioł L.

Polish Maritime Research

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1999

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nr 2

6-10

EN

Test results of the modified wood (lignomer) are presented with a view to its future application in shipbuilding industry. Influence of modificatin process of the wood on its strngth, water absorbabitility, impacct and fire resistance properties is highlighted.