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1

Trwałość samozagęszczalnej zaprawy ze spoiwa wieloskładnikowego pod wpływem zewnętrznych czynników chemicznych

Benguit Ammar, Boukhelkhal Aboubakeur, Azzouz Lakhdar

Cement Wapno Beton

|

2024

|

R. 29, nr 1

71--81

PL

Właściwości użytkowe betonów i zapraw są szczególnie powiązane z ich składem i stosunkiem wody do cementu. Zastosowanie cementu portlandzkiego [OPC] jako spoiwa zwiększa ciepło hydratacji i koszt cementu oraz emisję CO2. Zatem użytecznym rozwiązaniem może być zastosowanie spoiwa wieloskładnikowego poprzez zmniejszenie ilości OPC i wprowadzenie dodatków mineralnych. W tym badaniu OPC częściowo zastąpiono mączką marmurową [MP] w różnych proporcjach: 5, 10, 15 i 20% i zbadano wpływ MP na trwałość zapraw samozagęszczalnych [SCM] narażonych na agresję chemiczną. Zastosowano dwa roztwory korozyjne: siarczanu sodu [Na2SO4] i kwasu chlorowodorowego [HCl]. Stężenia roztworów wynosiły odpowiednio 5 i 1%. Wyniki wykazały, że zastosowanie proszku marmurowego korzystnie wpływa na poprawę odporności SCM na agresywne roztwory. Dodanie 20% MP zwiększyło odporność na działanie siarczanu sodu o 46% po 180 dniach. Stwierdzono, że stosowanie dodatku MP w zakresie od 10 do 20% zmniejsza utratę masy o 1 do 0,47%.

EN

The performance of concrete / mortar is specially related to their composition and water to cement ratio. The use of Ordinary Portland cement [OPC] as binder increases the hydration heat and cost of cement and CO2 emissions. So the use of composite binder by reducing the amount of OPC and introducing mineral additions can be a useful solution. In this study, OPC was partially substituted with marble powder [MP] at various percentages (5, 10, 15 and 20%) and the effect of MP on the durability of self compacting mortars [SCM] exposed to chemical aggressions was investigated. Two aggressive solutions were used sodium sulfate [Na2SO4] and hydrochloric acid [HCl]. The dosages of the solutions were 5 and 1%, respectively. The results revealed that the use of marble powder is beneficial for improving the resistance of SCM to aggressive solutions. Adding 20% MP increased the resistance against sodium sulfate attack by 46% at 180 days. Using MP with content ranged between 10 to 20% was found to reduce mass loss by 1 to 0.47%.

2

Performance of green high-strength concrete incorporating palm oil fuel ash in harsh environments

Zeyad Abdullah M., Johari Megat Azmi Megat, Aliakbar Ali, Magbool Hassan M., Majid Taksiah A., Aldahdooh Majed A. A.

Materials Science Poland

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2023

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Vol. 41, No. 4

24--40

EN

The corrosion of steel reinforcement by chloride is commonly recognized as a key factor that contributes to the degradation of durability in reinforced concreae structures. Using supplementary cementitious materials, such as industrial and agricultural waste materials, usually enhances the impermeability of the concrete and its corrosion resistance, acid resistance, and sulfate resistance. This study’s primary purpose is to examine the effects of replacing ordinary Portland cement (OPC) with ultrafine palm oil fuel ash (U-POFA) on the corrosion resistant performance of high-strength green concrete (HSGC). There were four HSGC mixes tested; the first mix contained 100% OPC, while the other mixes replaced OPC mass with 20%, 40%, and 60% of U-POFA. The performance of all HSGC mixes containing U-POFA on workability, compressive strength, porosity, water absorption, impressed voltage test, and mass loss was investigated at 7, 28, 60, and 90 days. Adding U-POFA to mixes enhances their workability, compressive strength (CS), water absorption, and porosity in comparison with mixes that contain 100% OPC. The findings clearly portrayed that the utilization of U-POFA as a partial alternative for OPC significantly enhances the corrosion-resistant performance of the HSGC. In general, it is strongly advised that a high proportion of U-POFA be incorporated, totaling 60% of the OPC content. This recommendation is the result of its significance as an environmentally friendly and cost-effective green pozzolanic material. Hence, it could contribute to the superior durability performance of concrete structures, particularly in aggressive environmental exposures.

3

Comparison Between Walkley-Black and Loss On Ignition Methods for Organic Matter Estimation in Different Moroccan Soils

El Mouridi Zineb, Ziri Rabea, Douaik Ahmed, Bennani Sahar, Lembaid Ibtissame, Bouharou Loubna, Brhadda Najiba, Moussadek Rachid

Ecological Engineering & Environmental Technology

|

2023

|

Vol. 24, iss. 4

253--259

EN

The present study aims to compare two different methods for the determination of soil organic matter (SOM); the wet acidified dichromate oxidation methods Walkley-Black (WB) and the combustion’s one (mass loss on ignition – LOI); in order to find out the best one in terms of suitability, environmentally-friendly, time-efficiency and economical benefit. Forty-five Moroccan soil samples (El Guich, Koudia and Merchouche area) from 0–20 cm depth with different classes, textures and organic matter contents were evaluated. According to the results, a strong linear relationship was observed between LOI-OM and WB-OM methods for all the sites. However, El Guich and Koudia recorded much larger regression coefficients (0.745*** and 0.611*** respectively) compared to Merchouche site (0.452**). Therefore, the SOM by walkley-Black method can be easily calculated from the LOI method at 500±25 ºC for 2 hours using linear equation in order to minimize the analysis time and consumption of chemicals for routine laboratory. In addition, it was noticed that the SOM contents calculated by the LOI method are higher in Merchouche soils compared to that of WB due to the presence of a large amount of clay minerals in the Merchouche soils (43.9 < %clay < 56.1) in comparison with those of El Guich (5 < %clay < 7.5) and Koudia (16.1 < %clay < 20.4). This study revealed that both methods were reliable but W.B method was more accurate and suitable for calcareous soils and those with high clay contents. However, LOI method is an accurate and beneficial for non-calcareous soils with low clay content.

4

Deformacje kompozytów cementowych w wysokich temperaturach

Plechawski Stanisław

Budownictwo i Prawo

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2023

|

R. 26, nr 3

25--30

PL

W artykule przedstawiono zagadnienia wpływu wysokich temperatur na deformacje kompozytów cementowych: beton, zaczyn i zaprawę. Jest to fragment szerzej prowadzonych badań własnych oddziaływania temperatur pożarowych na wybrane parametry struktury betonów, w których za wiodący temat uznano odporność na pękanie wyrażoną poprzez krytyczny współczynnik intensywności naprężeń KIC . Wykonano też inne, niezbędne badania kompozytów cementowych m.in. wytrzymałości na ściskanie, rozciąganie przy zginaniu i przez rozłupywanie, dynamicznego modułu sprężystości, a także badania odkształceń próbek betonu, zaczynu i zaprawy, zmiany ich objętości oraz ubytki masy, jak również obserwacje i badania SEM. Składy badanych kompozytów nie zawierały żadnych dodatków ani domieszek z uwagi na wiarygodność badań pod wpływem wysokich temperatur. Dodatkowe składniki w zależności od ich rodzaju, proporcji, pochodzenia itp. mogą wpływać na niejednoznaczność otrzymanych wyników. Publikowane przez różnych autorów badania nie zawsze są jednoznaczne i miarodajne dla wszystkich rodzajów betonu. Badania takie stanowią podstawę do oceny bezpieczeństwa, trwałości i niezawodności konstrukcji po pożarze.

EN

The article presents the issues of the impact of high temperatures on the deformation of cement composites: concrete, paste and mortar. It is a fragment of the widely conducted own research on the impact of fire temperatures on selected parameters of concrete structure, in which crack resistance expressed by the critical stress intensity factor KIC was recognized as the leading. Other necessary tests of cement composites were also carried out, including compressive strength, tensile strength at bending and splitting, dynamic modulus of elasticity, as well as testing deformations of concrete, paste and mortar samples, changes in their volume and weight loss, as well as SEM observations and tests. The compositions of the tested composites did not contain any additions or admixtures due to the reliability of the tests under the influence of high temperatures. Additional ingredients depending on their type, proportion, origin, etc. may affect the ambiguity of the results obtained. Studies published by various authors are not always unambiguous and authoritative for all types of concrete. Such studies are the basis for assessing the safety, durability and reliability of structures after a fire.

5

The coupling effect of silica fume and basalt fibers on workability and residual strength capacities of traditional concrete before and after freeze–thaw cycles

Guler Soner, Akbulut Zehra Funda

Archives of Civil and Mechanical Engineering

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2023

|

Vol. 23, no. 3

art. no. e173, 2023

EN

The combined use of silica fume (SF) and single and hybrid-basalt (BA) fibers can be a prominent option in diminishing the degradations of concrete after freeze–thaw (F–T) effects. This study investigated slump, mass loss (ML), abrasion loss (AL), residual compressive strength (RCS), and residual splitting tensile strength (RSTS) of SF and single- and hybrid-BA fiber-reinforced concrete after F–T cycles. The results demonstrated that although using SF and BA fibers together adversely affected the workability of the mixtures, they significantly improved the samples’ RCS and RSTS capacities. Besides, after F–T cycles, SF alone and with BA fibers are very efficient in reducing the AL of the samples. However, while using SF alone was somewhat effective in reducing the ML losses of the pieces, its use with single- and hybrid-BA fibers remained negligible. Furthermore, the hybrid use of BA fibers is more efficient in recovering concrete samples' workability and AL, RCS, and RSTS capacities than the single use. Compared to room conditions, after the 180 F–T cycles, the AL of the R0 control sample increased by 29.24%, while the SF and BA fiber-added R1–R7 samples ranged from 7.11% to 10.17%. Additionally, after the 180 F–T cycles, while the RSTS capacity of R0 control concrete decreased by 27.06%, the reduction in RSTS capacity of R1–R7 BA fiber-reinforced concrete ranged from 13.42% to 23.63%. This study is expected to constitute an important reference to the literature on how SF pozzolanic admixture and BA fiber additives play a role in improving the behavior of concrete against F–T cycles.

6

The Role and Effectiveness of the MBP Installation in Poland Based on Selected Examples

Wiśniewska Marta, Lelicińska-Serafin Krystyna

Civil and Environmental Engineering Reports

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2019

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Vol. 29, no. 2

1--12

EN

The paper presents examples of installations for the mechanical and biological treatment of municipal waste in Poland. Each of the presented installations is defined as a regional municipal waste treatment installation (RIPOK). Their technological solutions and work efficiency have been compared in this study. In addition, the loss of waste mass as a result of processes occurring in the biological part of individual installations was calculated in the research. The paper refers to the National Waste Management Plan (KPGO 2022) regarding the circular economy. As intended by the circular economy, MBP installations will be transformed into installations that will treat selectively collected municipal waste and become Regional Recycling Centers (RCR).

7

An Analysis of Selected Functional Characteristics of Temporary Restorative Materials Used in Conservative Dentistry

Słomion M., Matuszewski M., Styp-Rekowski M.

Tribologia

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2018

|

nr 5

101--108

EN

An important factor in endodontic therapy is forming a tooth seal as a temporary restoration, which prevents leakage of medicines into the oral cavity, infiltration of microorganisms, and contamination of the root canal system by fluids or food debris. Suitable physicochemical analysis and usability evaluation of restorative materials, i.e. microhardness, abrasion and compression resistance, surface structure, behaviour at different temperatures, the sealing of tooth margins, the ease of insertion and removal, allow one to choose the material that will be most favourable for medical treatment. The aim of the study is to determine, in vitro, changes of the surface structure that arise over time in commonly used preparations for temporary dental fillings. The results showed significant structural changes occurring over time, especially at a temperature of 37°C (inflammation to be), which, for a long-term use, may have a negative impact on the treatment.

PL

Istotnym czynnikiem w prowadzonej terapii endodontycznej jest utworzenie uszczelnienia zęba w postaci tymczasowego uzupełnienia, które zapobiega wyciekaniu leków do jamy ustnej, dostawaniu się drobnoustrojów oraz zanieczyszczaniu kanałów korzeniowych przez płyny czy resztki pokarmu. Przeprowadzenie odpowiedniej analizy fizykochemicznej, a także oceny użytkowej materiałów odtwórczych, tj. mikrotwardości, odporności na ściskanie i ścieranie, struktury powierzchni, zachowania w różnych temperaturach, szczelności brzeżnej, łatwości wprowadzania i usuwania, pozwala na dobór materiału, który będzie najkorzystniejszy dla prowadzonego leczenia. Celem badań było określenie zmian struktury powierzchni powstających w czasie pod wpływem oddziaływania środowiska oraz odporności na zużywania ścierne dla stosowanych preparatów do tymczasowych wypełnień stomatologicznych. Wyniki wykazały istotne zmiany struktury powstające w czasie, szczególnie w temperaturze 37°C (teoretycznie początek stanu zapalnego), co przy dłuższym stosowaniu może mieć negatywny wpływ na prowadzone leczenie.

8

Examination of remaining zinc coating on old corrugated steel culverts under railway

Hansing L., Cederqvist S.

Archiwum Instytutu Inżynierii Lądowej

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2017

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Nr 23

125--131

EN

In this paper the authors present measurements of the zinc coating thickness performed on old corrugated steel culverts under railway in Sweden. The measurements were performed in the summer of 2015. The object of the study is to have an indication on how hot dip galvanized corrugated steel culverts withstand real conditions. This information forms an important basis for the decision on possible life time expectancies for those structures.

9

Decomposition Rate, and Carbon and Nitrogen Dynamics of Sphagnum Litter : Lessons from a Peat Bog

Péli E. R., Nagy J., Cserhalmi D.

Polish Journal of Ecology

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2016

|

Vol. 64, nr 2

231--240

EN

Decomposition rates and changes of carbon and nitrogen contents of Sphagnum litter in mire vegetation can help to explore the ecological effects of climate change and the role of environmental factors from a local to an ecosystem scale. The objective of the study was to determine the relationship between mentioned parameters in small and isolated Sphagnum dominated mires. Measurements had been conducted throughout a year by placing litterbags filled with Sphagnum biomass in three vegetation types (open peat bog, poor fen, alder carr) of a mire ecosystem in Hungary. Peat decomposition rates differed to a great extent; the slowest decomposition rate (39.1±9.52%) was in the alder carr, indicating that slower decomposition could be characteristic for this kind of vegetation type of mire. Between Sphagnum dominated microhabitats, open peat bog showed medium (65.57±4.05) while poor fen the fastest (68.61±5.5) rates in decomposition. The C/N ratio of the Sphagnum litter showed significant decrease (P <0.005) in all studied micro-environments. Slower N release was observed from litter of Alnus dominated association (31.3±6.9%) compared to Sphagnum dominated ones (56.5±8.3%). Our findings showed that the decomposition rates were more dependent on vegetation type than C/N ratio and this relationship was also revealed at a small spatial scale.

10

Biosuszenie pofermentu z biogazowni rolniczych

Białowiec A., Wiśniewski D., Pulka J., Siudak M., Jakubowski B., Myślak B.

Rocznik Ochrona Środowiska

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2015

|

Tom 17, cz. 2

1554--1568

EN

Anaerobic digestion residue represents a nutrient rich resource which, if applied back on land, can reduce the use of mineral fertilizers and improve soil fertility. However, dewatering of digestate may be recommended in certain situation. Limited applicability of digestate as fertilizer may appear, especially in winter, during the vegetation period or in areas where advanced eutrophication of arable land and water bodies is developing. The use of digestate may be also governed by different laws depending on whether it is treated as fertilizer, sewage sludge or waste. The solution for thus problem may by application of biodrying process. The aim of this paper is to present the possibilities of digestate from agricultural biogas plant drying in biodrying process, and analysis of its kinetic and efficiency. Dewatered digestate from agricultural biogas plant, with initial moisture of 78%, was mixed with wood chips in proportion 45:55, respectively. The mixture was placed in container reactor, and aerated during 4 weeks. During the experiment the temperature in the reactor, weight of the digestate, and energy demand was measured. Due to biodrying process, with mean air flow rate 0.025 m3/kg.h, 502 kg mass loss was achieved, what consists 76% of the initial weight of the digestate. Mean temperature in the bioreactor during first 10 days, fluctuated between 55 to 60°C. After that, gradual decrease of the temperature to 40°C in the end of 3rd week was observed. During last week the intense cooling of the bioreactor to final temperature below 20°C was observed. It was determined, that digestate mass loss had I-order reaction character. The k constant rate value was estimated, which was on the level of 0.00068 [1/h]. Total energy demand was 14.792 kWh, what relates to 0.0295 kWh of used energy per kg of mass removed.

11

Zmiana prędkości rozchodzenia się fali ultradźwiękowej w cegle ceramicznej eksponowanej w siarczanowym i chlorkowym środowisku korozyjnym

Stryszewska T., Kańka S.

Przegląd Budowlany

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2015

|

R. 86, nr 6

92--96

PL

Wieloletni okres eksploatacji cegły ceramicznej w różnych warunkach zwłaszcza w obecności wilgoci sprzyja postępującym zmianom, które wraz z upływem czasu mogą powodować stopniową utratę właściwości użytkowych. Proces ten jest związany między innymi z gromadzeniem się w teksturze cegły ceramicznej soli pochodzących ze środowiska zewnętrznego. Mogą one powodować znaczne ciśnienia związane z krystalizacją w porach materiału. Ponadto w reakcji ze składnikami czerepu mogą tworzyć się produkty korozji. Obecność jednych i drugich sprzyja utracie właściwości użytkowych materiału. W związku z tym podjęto badania, których celem było określenie zdolności akumulacji różnych soli w czerepie cegły ceramicznej zwykłej. Proces akumulacji oceniano na podstawie pomiarów grawimetrycznych oraz pomiarów prędkości przepływu fal ultradźwiękowych.

EN

The long-term utilisation of the ceramic bricks in different conditions, particularly in the presence of moisture, induces the progressive changes, which over time can initiate a gradual loss of performance. This process is related to, inter alia, the collection in the texture of ceramic bricks the salts, derived from the external environment, which may crystallize in the pores of the material. Furthermore, they can form corrosion products in the reaction with the components of the shard. The presence of both enables the loss of performance of the material. Therefore, the studies were undertaken aimed at determining the ability of the various salts to accumulate in the shard of an ordinary ceramic bricks. The accumulation was evaluated on the basis of the gravimetric measurements and measurements of the velocity of ultrasonic waves.

12

Thermogravimetric analysis of commercial thermally modified wood

Grześkowiak W. Ł., Bartkowiak M.

Drewno : prace naukowe, doniesienia, komunikaty

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2015

|

vol. 58, nr 194

23--36

EN

In the article the results are shown of a thermogravimetric analysis of four thermally modified wood species. Thermally modified wood before and after the extraction process was used for the tests. The extraction process had no significant effect on changes in the thermal characteristics either in the raw wood or in the modified wood, irrespective of the tested wood species.

13

Wpływ temperatury na ubytek masy i gęstość objętościową skał osadowych

Sygała A., Bukowska M.

Bezpieczeństwo Pracy i Ochrona Środowiska w Górnictwie

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2015

|

nr 11

9--17

PL

W artykule przedstawiono wyniki badań ubytku masy oraz gęstości objętościowej iłowców i piaskowców o różnym uziarnieniu, poddanych działaniu temperatury z zakresu od 100 do 1000°C. Próbki skał pobrano z różnych rejonów GZW, z wszystkich obecnie eksploatowanych ogniw litostratygraficznych karbonu produktywnego. Na podstawie wyników badań stwierdzono zmianę ubytku masy wraz ze wzrostem uziarnienia. Największe zmiany zaobserwowano wśród iłowców, natomiast najmniejsze w piaskowcach gruboziarnistych. W przypadku zmian wartości gęstości objętościowej, po działaniu temperatury 600°C wykazano różne jej zmiany, w porównaniu z wartością w stanie powietrzno-suchym. Po działaniu temperatury 1000°C, wszystkie badane skały wykazały natomiast spadek wartości gęstości objętościowej.

EN

The article presents results of research into changes in loss of mass and bulk density of sedimentary rocks, under influence of temperature of between 100 and 1000°C. Sedimentary rocks (claystones and sandstones of different grain size), collected in different areas of Upper Silesian Coal Basin (GZW), from all currently operated carboniferous stratigraphic groups. Based on the results, there is a change of loss mass with increasing grain size. The biggest changes were observed among claystones while the smallest changes were characterized by coarse-grained sandstones. In the case of changes in the bulk density after the treatment of temperature 600°C showed various changes in the parameter compared to the value established in the air-dry state. After a temperature 1000°C all test sedimentary rocks, showed a reduction in the bulk density.

14

Study of TATP: Mass Loss and Friction Sensitivity During Ageing

Matyáš R., Šelešovský J., Musil T.

Central European Journal of Energetic Materials

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2012

|

Vol. 9, nr 3

251-260

EN

Triacetone triperoxide (3,3,6,6,9,9-hexamethyl-1,2,4,5,7,8-hexoxonane; TATP) is one of the most frequently used improvised explosives, often misused worldwide. In our previous studies, we had observed that the kind of acid used to catalyse its formation has a significant influence on TATP's properties. TATP was prepared using five different acids that are often used in improvised conditions. All of the samples were subjected to natural ageing in both open and closed vials at laboratory temperature. During ageing, TATP sublimes and decomposes. The changes in crystal size and shape after ageing were documented by optical microscopy. The mass loss was monitored about every third day during ageing. Samples prepared using sulphuric and perchloric acids lose weight more quickly than the others due to chemical decomposition. The friction sensitivity was determined for all samples before and after ageing. Neither the type of acid used nor the influence of closing the vials had any significant influence on the friction sensitivity after ageing. The friction sensitivity of all tested samples of TATP was about the same ? between that of lead azide and that of mercury fulminate.

15

Utilization of thermal sprayed coatings for purpose of converter hood repairing

Brezinova J., Egri M., Guzanova A., Vinas J.

Rudy i Metale Nieżelazne

|

2010

|

R. 55, nr 6

360-365

EN

The contribution deals with repairing of converter hoods by thermal spraying technique. There were used two types of sprayed wires - formerly used NiCr and new filled wire marked as DURMAT. Microhardness of thermally sprayed coatings was measured by Vickers indenter, wear resistance of coatings was checked by erosion test simulated by abrasive grit blasting. EDX analysis proved presence of particular structural phases. Higher microhardness values were found in DURMAT coating and this property conduced to higher wear resistance of this coating in comparison with previously used NiCr coating. Reached results showed, that new coating marked DURMAT-AS-761 proved better properties in comparison with previously used coating from point of view of chemical composition, microhardness and also erosive wear evaluation.

PL

W artykule przedstawiono technologię regeneracji pokryw konwerterów poprzez nanoszenie cieplne warstwy wierzchniej. W badaniach stosowano dwa rodzaje materiału: NiCr oraz drut z rdzeniem oznaczony DURMAT. Pomiary mikrotwardości nanoszonych powłok wykonywano za pomocą próby Vickersa, natomiast pomiary zużycia erozyjnego zrealizowano poprzez czyszczenie strumieniowo-ścierne. Analiza EDX nałożonej powierzchni wykazała występowanie wyodrębnionych faz strukturalnych. Powłoki DURMAT-AS-761, w porównaniu z dotychczas stosowanymi pokryciami NiCr, wykazały wyższą mikrotwardość oraz odporność na zużycie ścierne.

16

The experimental research on adhesion and mass loss for reinforcing steel covered with polymeric sulphuric composites

Książek M.

Kompozyty

|

2010

|

R. 10, nr 4

374-379

EN

This paper presents the results of the experimental research and analyses indicating the usefulness of polymer sulphur composites to the protection against corrosion of reinforcement. In paper presents materials also the domain of the personal investigations and the methodology are definite. After the analyze of the initial results the optimum compositions have been chosen to the experimental research. In paper the review of the literature have been done, among other things about select using polymer sulphur composites in buildings, about the methods of the surface protection against corrosion of reinforcement and about the methods of the evaluation of protection layer on these materials. The experimental programme comprised the adhesion of sulphur polymer composite layer to rebars under tension and bending, adjacent adhesion of sulphur polymer composite layer to reinforcing bars, adjacent adhesion of sulphur polymer composite to rebars in pushed-out test, adjacent adhesion of concrete to rebars coated with sulphur polymer composite, and mass loss of plain rebars in aqueous solutions of acids, hydroxides and salts and in water. In paper the usefulness of polymer sulphur composites to the surface protection against corrosion of the reinforcement have been evaluated.

PL

Przedstawiono rezultaty badań eksperymentalnych i analiz wykazujących przydatność polimerowych kompozytów siarkowych do ochrony przed korozją stali zbrojeniowej. W artykule podano skład materiału, rezultaty badanych właściwości i metodykę przeprowadzonych badań. Wybrano do dalszych badań polimerowy kompozyt siarkowy, charakteryzujący się najkorzystniejszymi, spośród badanych, właściwościami. Dokonano przeglądu literaturowego, między innymi, w zakresie wybranych zastosowań polimerowych kompozytów siarkowych w budownictwie, metod i sposobów powierzchniowej ochrony przed korozją stali zbrojeniowej, a także metod i sposobów oceny szczelności warstw zabezpieczających ten materiał przed korozją. Przeprowadzono badania eksperymentalne dla wybranych polimerowych kompozytów siarkowych. Program badań eksperymentalnych obejmował zbadanie: przyczepności warstwy polimerowego kompozytu siarkowego do prętów zbrojeniowych rozciąganych i zginanych, przyczepności stycznej warstwy polimerowego kompozytu siarkowego do prętów zbrojeniowych, przyczepności stycznej polimerowego kompozytu siarkowego do prętów zbrojeniowych wypychanych z tego kompozytu, przyczepności stycznej betonu do prętów zbrojeniowych pokrytych warstwą polimerowego kompozytu siarkowego i ubytku masy prętów zbrojeniowych gładkich w roztworach wodnych kwasów, wodorotlenków i soli oraz w wodzie. Wykazano przydatność polimerowych kompozytów siarkowych do powierzchniowej ochrony przed korozją stali zbrojeniowej.

17

Influence of mass changes of flying objects on their dynamic features

Wiśniewski W.

Journal of KONES

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2010

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Vol. 17, No. 4

591-598

EN

The aim of this work is the experimental study of the weight loss impact on the properties of flying objects. Work is hased on the results of resonance tests of the helicopter, gliders and military aircraft. In the presented flying objeets group the possible occurrence of weight losses during the flight are up to 50%. The paper posed the following questions: How big can be, in practice, the weight loss during the flight? To which resonance the mass loss has the greatest impact? How and by what rules the map of resonances changes? Does in the process of weight loss there are other, worth-knowing events? Gliders, airplanes and a helicopter were investigated in the Resonance Test Laboratory of Institute of Aviation. The author has organized and for over 20 years led the Resonance Test Laboratory at the Institute of Aviation, in which he made or directed the investigations of dozens of aircraft, gliders, helicopters and their elements and components. Effect of weight loss on the flying objeets properties is one of several ,,unusual" research topics phenomena, which the author observed during a standard resonance tests. The resonance of the mode shape of Jantar 15 glider, comparison of the relative increase in the frequencies of the resonances with mode shape for SZD-50 Jantar 15-2 and IS-2 Revelation gliders, results of investigations of the underwing stores loss of mass impact on the „Pattem" aircraft resonances freąuencies, the resonance frequency of the 1-22 Iryda aircraft are presented in the paper. The resonance of the mode shape of Jantar 15 glider, comparison of the relative increase in the frequencies of the resonances with mode shape for SZD-50 Jantar 15-2 and IS-2 Revelation gliders, results of investigations of the underwing stores loss of mass impact on the ,,Pattern" aircraft resonances frequencies, the resonance frequency of the 1-22 Iryda aircraft are presented in the paper.

18

Wear diagnosing of selected material couples

Guzanova A., Brezinova J.

Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika

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2009

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z. 77 [269]

11-18

EN

The paper deals with the evaluation of material wear of injection moulds made of aluminium alloy Alumec 89 and copper alloy Moldmax HH in friction couples with plastomer materials with various filler contents. The friction relations in injection moulding were simulated in an adhesion dry wear test using an Amsler machine, with an area contact of the friction couple materials. The wear intensity was evaluated by determination of friction coefficient and relative wearing by the mass loss. Surface morphology changes of evaluated alloys after wear were analysed simultaneously.

PL

Opracowanie zawiera wyniki oceny zużycia ściernego części form wykonanych ze stopu aluminium Alumec 89 oraz stopu miedzi Moldmax HH podczas wtryskiwania materiałów polimerowych z różną zawartością wypełniaczy. Proces wtryskiwania byt symulowany podczas testowania na maszynie wytrzymałościowej Amsler par materiałów w warunkach tarcia suchego. Intensywność zużycia była określana poprzez wartość współczynnika tarcia oraz poprzez ubytek masy próbek. Jednocześnie, po zakończeniu testu dokonano oceny zmian morfologii powierzchni próbek.

19

Effect of abrasion on the air permeability & mass loss of breathable-coated fabrics

Padleckienė I., Petrulis D.

Fibres & Textiles in Eastern Europe

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2009

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Vol. 17, no. 2 (73)

50--54

EN

This paper presents a study on air permeability and relative mass loss in abraded breathable-coated fabrics. The abrasion treatment of different structured samples as well as the outer and reverse sides of specimens was done on a Martindale tester, varying the number of abrasion cycles. Considerable attention was devoted to the importance of the coating and textile substrate abrasion. Trends in the relationships between the abrasion cycles and the above-mentioned properties of the coated fabrics are discussed. The results support the nonlinear function approach nonlinear function.

PL

Artykuł przedstawia badania przepuszczalności powietrza względnych strat masy oddychających tkanin membranowych poddanych ścieraniu. Ścieraniu poddano zróżnicowane próbki tkanin po obydwu stronach. Stosowano urządzenie Martindale zmieniając ilość cykli ścierania. Specjalną uwagę poświęcono ścieraniu warstwy pokrycia. Przedyskutowano tendencje w zależnościach pomiędzy ilością cykli ścierania i właściwościami tkanin. wyniki badań wskazują na istnienie zależności nieliniowych.

20

Wpływ wysokiej temperatury na wybrane właściwości betonu wysokowartościowego z dodatkiem włókien polipropylenowych

Hager I., Tracz T.

Cement Wapno Beton

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2009

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R. 14/76, nr 1

3-10

PL

Zbadano właściwości próbek z wysokowartościowego betonu bez i z dodatkiem włókien polipropylenowych. Stwierdzono, że to rozproszone zbrojenie zwiększa wytrzymałość próbek po wygrzewaniu w temperaturach 100,120,160,200,400 i 600°C. Natomiast przepuszczalność próbek zawierających dodatek włókien ulega bardzo znacznemu zwiększeniu. Zwiększa się także nasiąkliwość powierzchniowa tych próbek. Autorzy stawiają wniosek, że ten wzrost przepuszczalności będzie zwiększał odporność betonu wysokowartościowego na działanie wysokich temperatur.

EN

Several properties of the HPC samples without and with polypropylene fibres addition. It was found that the dispersed reinforcement with polypropylene fibres increase the compressive strength after heat treatment of samples at 100°C to 600°C. However, the permeability of samples was significantly increased. Also the water surface absorption of these samples was drastically enhanced. The author made the conclusion that this significant increase of permeability in case of HPC samples with addition of polypropylene fibres will cause the enhancement of durability of this concrete at elevated temperature.