Wyniki wyszukiwania - Biblioteka Nauki

1

Phase Analysis of Different Liquid Ratio on Metakaolin/Dolomite Geopolymer

100%

Sauffi A. S. , Ibrahim W. M. W. , Al Bakri Abdullah M. M. , Ibrahim M. , Ahmad R. , Zaidi F. A.

Archives of Metallurgy and Materials

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2022

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tom Vol. 67, iss. 1

247--250

EN

Geopolymer is widely studied nowadays in various scope of studies. Some of the ongoing studies are the study of the various materials towards the geopolymer strength produced. Meanwhile, some of the studies focus on the mixing of the geopolymer itself. This paper discussed the phase analysis of metakaolin/dolomite geopolymer for different solid to the liquid ratio which was, 0.4, 0.6, 0.8, and 1.0, and the properties that affected the geopolymer based on the phases. The constant parameters in this study were the percentage of metakaolin and dolomite used. The metakaolin used was 80% meanwhile dolomite usage was 20%. Besides that, the molarity of NaOH used is 10M and the alkaline activator ratio used is 2.0. All the samples were tested at 28 days of curing. The results show that the 0.8 solid to the liquid ratio used gave better properties compare to other solid to liquid ratio. The phases analyzed were quartz, sillimanite, mullite, and faujasite. The 0.8 S/L ratio shows the better properties compared to others by the test of phase analysis, compressive strength morphology analysis, and functional group analysis.

2

The corrosion resistance of the base geopolymer fly ash

100%

Mazur P. , Mikuła J. , Kowalski J. S.

Advances in Science and Technology. Research Journal

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2013

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tom Vol. 7, nr 19

88--92

EN

The article presents research on a new engineering material which becomes geopolymer. This is the material used to form a protective layer, to provide a high moisture absorption capacity, however, its composition is highly alkaline and, therefore, its absorption does not affect adversely the protected structures. The research included the effects of various corrosive environments for a change in weight of the test samples during the test, as well as the surface structure on a macroscopic scale.

3

The Investigation of Ground Granulated Blast Furnace Slag Geopolymer at High Temperature by Using Electron Backscatter Diffraction Analysis

100%

Aziz I. H. , Al Bakri Abdullah M. M. , Salleh M. A. A. M. , Yoriya S. , Razak R. A. , Mohamed R. , Baltatu M. S.

Archives of Metallurgy and Materials

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2022

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tom Vol. 67, iss. 1

227--231

EN

This paper elucidated the potential of electron backscatter diffraction analysis for ground granulated blast furnace slag geopolymers at 1000°C heating temperature. The specimen was prepared through the mechanical ground with sandpaper and diamond pad before polished with diamond suspension. By using advanced technique electron backscatter diffraction, the microstructure analysis and elemental distribution were mapped. The details on the crystalline minerals, including gehlenite, mayenite, tobermorite and calcite were easily traced. Moreover, the experimental Kikuchi diffraction patterns were utilized to generate a self-consistent reference for the electron backscatter diffraction pattern matching. From the electron backscatter diffraction, the locally varying crystal orientation in slag geopolymers sample of monoclinic crystal observed in hedenbergite, orthorhombic crystal in tobermorite and hexagonal crystal in calcite at 1000°C heating temperature.

4

Study of Zn(II) ion removal from galvanic sludge by geopolymers

100%

Sitarz-Palczak E.

Archives of Environmental Protection

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2023

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tom Vol. 49, no 4

11--20

EN

The galvanic sludges contain a number of toxic heavy metals, potentially mobilized as chemically active ions under environmental conditions as. This study explores the application of fly ash-based geopolymers for the removal of Zn ions from galvanizing sludge. In this study, geopolymers, synthesized via the geopolymerization method, were used to remove Zn from post-galvanized sewage sludge. Two types of geopolymers were used, derived from ash from coal combustion and biomass combustion. Structural, morphological, and surface properties were characterized using FTIR and SEM, respectively. In addition, BET and Langmuir isotherms, along with analyses such as t-Plot and BJH method for porous solids were conducted. The results indicate that the geopolymer derived from coal combustion ash is a more effective sorbent for Zn(II) ions, exhibiting a removal efficiency of 99.9%, compared to 40.7% for the geopolymer derived from biomass combustion ash. The FTIR spectra analysis reveals the presence of bonds between the -OH and/or Si-OH groups on the geopolymers’ surface and the Zn(II) ions. The environmentally and economically advantageous process maximizes the recovery of a valuable component at minimal cost, yielding relatively clean monometallic waste suitable for reuse.

PL

Osady galwaniczne zawierają szereg toksycznych metali ciężkich, które w warunkach środowiskowych mogą być mobilne jako chemicznie aktywne jony. W pracy badano możliwość wykorzystania geopolimerów na bazie popiołów lotnych do usuwania jonów Zn z osadu galwanizacyjnego. W pracy do usuwania Zn z galwanicznych osadów ściekowych wykorzystano geopolimery przygotowane metodą geopolimeryzacji. Zastosowano dwa rodzaje geopolimerów, otrzymywane na bazie popiołów ze spalania węgla i popiołów ze spalania biomasy. Strukturę, morfologię i właściwości powierzchni scharakteryzowano odpowiednio za pomocą FTIR i SEM. Dodatkowo wyznaczono izotermę BET i Langmuira oraz przeprowadzono analizę tych izoterm dla ciał porowatych (metoda t-Plot i metoda BJH). Wykazano, że geopolimer otrzymany z popiołów ze spalania węgla jest skuteczniejszym sorbentem dla jonów Zn(II). Skuteczność usuwania jonów Zn(II) dla geopolimeru na bazie popiołów ze spalania węgla wynosi 99,9%, a dla geopolimeru na bazie popiołów ze spalania biomasy 40,7%. Otrzymane rezultaty są wynikiem powstawania wiązań pomiędzy grupami -OH i/lub Si-OH obecnymi na powierzchni zastosowanych geopolimerów a jonami Zn(II), których obecność stwierdzono na podstawie analizy widm FTIR. Procedura ta jest korzystna z ekologicznego i ekonomicznego punktu widzenia ponieważ zapewnia maksymalny odzysk cennego składnika przy możliwie najniższych kosztach. Ponadto, pozwala na uzyskanie stosunkowo czystych odpadów monometalicznych, które można ponownie wykorzystać

5

Infrared Imaging as a Non-Destructive Testing Method for Geopolymer Concrete

100%

Kusbiantoro A. , Ismail A. H. , Jema’in S. K. , Muthusamy K. , Zainal F. F.

Archives of Metallurgy and Materials

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2023

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tom Vol. 68, iss. 3

1047--1052

EN

Non-destructive testing (NDT) is generally used to estimate the compressive strength of concrete material without compromising its structural integrity. However, the available testing methods on the market have particular limitations that may restrict the accuracy of the results. Therefore, this study aimed to develop a new technique for measuring the compressive strength of geopolymer concrete using infrared imaging analysis and Thermal Diameter Variation (TDV) rate. The compressive strength range was designed within the target strength of 20, 30 and 40 MPa. The infrared image was captured on the preheated concrete surface using FLIR-ONE infrared camera. Based on the correlation between TDV rate and compressive strength, higher accuracy was obtained in the orange contour with an R2 of 0.925 than in the red contour with an R2 of 0.8867. It is apparent that infrared imaging analysis has excellent reliability to be used as an alternative NDT by focusing on the warmer region during the procedure.

6

Assessment of Geopolymer Concrete for Underwater Concreting Properties

100%

Zaidi F. H. A. , Ahmad R. , Al Bakri Abdullah M. M. , Wan Ibrahim W. M. , Aziz I. H. , Junaidi S. , Luhar S.

Archives of Metallurgy and Materials

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2022

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tom Vol. 67, iss. 2

677--684

EN

For ages, concrete has been used to construct underwater structures. Concrete laying underwater is a very complex procedure important to the success or failure of underwater projects. This paper elucidates the influence of alkali activator ratios on geopolymers for underwater concreting; focusing on the geopolymer concrete synthesized from fly ash and kaolin activated using sodium hydroxide and sodium silicate solutions. The geopolymer mixtures were designed to incorporate multiple alkali activator ratios to evaluate their effects on the resulting geopolymers’ properties. The fresh concrete was molded into 50 mm cubes in seawater using the tremie method and tested for its engineering properties at 7 and 28 days (curing). The control geopolymer and underwater geopolymers’ mechanical properties, such as compressive strength, water absorption density, and setting time were also determined. The differences between the control geopolymer and underwater geopolymer were determined using phase analysis and functional group analysis. The results show that the geopolymer samples were optimally strengthened at a 2.5 alkali activator ratio, and the mechanical properties of the control geopolymer exceeded that of the underwater geopolymer. However, the underwater geopolymer was determined to be suitable for use as underwater concreting material as it retains 70% strength of the control geopolymer.

7

Effect of Silica Fume and Alumina Addition on the Mechanical and Microstructure of Fly Ash Geopolymer Concrete

100%

Min F. S. , Yong H. C. , Ming L. Y. , Al Bakri Abdullah M. M. , Razi H. M. , Low F. W. , Ng H.-T. , Ng Y.-S.

Archives of Metallurgy and Materials

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2022

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tom Vol. 67, iss. 1

197--202

EN

This paper discussed the effect of the addition of silica fume (2 wt.% and 4 wt.%) and alumina (2 wt.% and 4 wt.%) on the properties of fly ash geopolymer concrete. The fly ash geopolymer concrete achieved the highest 28-day compressive strength with 2 wt.% of silica fume (39 MPa) and 4 wt.% of alumina (41 MPa). The addition of 2 wt.% of silica fume increased the compressive strength by 105% with respect to the reference geopolymer (without additive). On the other hand, the compressive strength surged by 115% with 4 wt.% of alumina compared to the reference geopolymer. The addition of additives improved the compactness of the geopolymer matrix according to the morphology analysis.

8

Effect of Solid-To-Liquids and Na2SiO3-To-NaOH Ratio on Metakaolin Membrane Geopolymers

88%

Ibrahim M. , Wan Ibrahim W. M. , Al Bakri Abdullah M. M. , Sauffi A. S. , Vizureanu P.

Archives of Metallurgy and Materials

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2022

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tom Vol. 67, iss. 2

695--702

EN

Geopolymer is synthesized by polycondensation of SiO4 and AlO4 aluminosilicate complexes, tetrahedral frames linked with shared sialate oxygen. This paper studies the effect of the solids-to-fluids (S/L) and Na2SiO3/NaOH proportions on the preparing of metakaolin inorganic membrane geopolymer. By consolidating a mixture of metakaolin with sodium hydroxide, sodium silicate and foaming agent, the geopolymer membrane was made in required shape about 1 cm and cured at 80°C for 24 hours. After the curing process, the properties of the samples were tested on days 7. Sodium silicate (Na2SiO3) and sodium hydroxide (NaOH) solution were utilized as an alkaline activator with a NaOH fixation fixed at 10 M. The geopolymer inorganic membrane tests were set up with various S/L proportions (0.8, 1.0, 1.2 and 1.4) and Na2SiO3/NaOH proportions (0.5, 1.0, 1.5, 2.0 and 2.5). Aluminium (Al) powder as a foaming agent was used to create bubbles in porous structure and provide details on the development of membrane geopolymers. This metakaolin membrane, based on the geopolymer, was synthesized by a suspension that depends on the fast cementing mechanism of high-temperature slurries. Porous geopolymeric circles provided a homogeneous composition and quantitative distribution of pores. The water absorption, density, impact toughness testing and microstructure analyses were studied. However, considering the promising results, an adjustment in the mix design of the metakaolin inorganic membrane geopolymer mixtures could increase their mechanical properties without negatively affecting the mechanical properties and porosity, making these sustainable materials a suitable alternative to traditional porous cement concrete.

9

Influence of Sintering Temperature on the Pore Structure of an Alkali-Activated Kaolin Based Geopolymer

88%

Ramli M. I. I. , Salleh M. A. A. M. , Aziz I. H. , Zaimi N. S. M. , Amli S. F. M. , Abdullah M. M. A. B.

Archives of Metallurgy and Materials

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2023

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tom Vol. 68, iss. 3

987-989

EN

Kaolin-based geopolymers are alternatives for producing high-strength ceramics for construction materials. Creating high-performing kaolin ceramics utilizing the regular technique requires a high handling temperature (higher than 1200°C). Thus, the structure and properties such as pore size and distribution are affected at higher sintering temperatures. Along these lines, information with respect to the sintering system and related pore structure is essential for advancing the properties of the previously mentioned materials. This study investigated the microstructure and the density of a kaolin-based geopolymer at various sintering temperatures. The unsintered sample has the highest density of 1610 kg/cm3 , while the samples sintered at 1100°C haves the lowest density of 1203 kg/cm3 . The result also shows that increasing the sintering temperature to 1100°C resulted in increasing the water absorption of the kaolin-based geopolymer ceramic.

10

Impact of Sulfate in the Sand on the Absorption and Density of Metakaolin-Based Geopolymer Mortar

88%

Thamer S. Y. , Al-Jaberi L. A.

Journal of Ecological Engineering

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2023

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tom Vol. 24, nr 1

328--335

EN

The advancement of cement alternatives in the construction materials field is fundamental to sustainable development. Geopolymer is the optimal substitute for ordinary portland cement, which produces 80% less CO2 emissions. Metakaolin was used as one of the raw materials in the geopolymerization process. This research examined the influence of three different percentages of sulfate (0.00038, 1.532, and 16.24)% in sand per molarity of NaOH on the absorption and density of metakaolin-based geopolymer mortar (MK-GPM). Samples were prepared with two different molarities (8M and 12M) and cured at room temperature. The best results obtained for geopolymer mortar in the absorption and density test were (3.89%) and (2280 kg/m3), respectively, recorded with 12M with the lowest sulfate content (0.00038%) at 90 days. Moreover, it has been observed that the absorption percentage increased along with sulfate content in the sand, and an inverse relationship was recorded between the increasing sulfate percentages in the sand and density values of (MK-GPM).

11

Effect of NaOH Molar Concentration on Microstructure and Compressive Strength of Dolomite/Fly Ash-Based Geopolymers

88%

Azimi E. A. , Mohd Salleh M. A. A. , Al Bakri Abdullah M. M. , Aziz I. H. A. , Hussin K. , Chaiprapa J. , Vizureanu P. , Yoriya S. , Nabiałek M. , Wyslocki J. J.

Archives of Metallurgy and Materials

|

2022

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tom Vol. 67, iss. 3

993--998

EN

Dolomite can be used as a source of aluminosilicate to produce geopolymers; however, this approach is limited by its low reactivity. This study analyzes the viability of producing geopolymers using dolomite/fly-ash with sodium silicate and NaOH solutions (at multiple concentrations) by determining the resultant geopolymers’ compressive strengths. The dolomite/fly-ash-based geopolymers at a NaOH concentration of ~22 M resulted in an optimum compressive strength of 46.38 MPa after being cured for 28 days, and the SEM and FTIR analyses confirmed the denser surface of the geopolymer matrix. The synchrotron micro-XRF analyses confirmed that the Ca concentration exceeded that of Si and Mg, leading to the formation of calcium silicate hydrate, which strengthens the resulting geopolymers.

12

Review on Mechanical Properties of Metakaolin Geopolymer Concrete by Inclusion of Steel Fibers

88%

Faris M. A. , Al Bakri Abdullah M. M. , Muniandy R. , Ramasamy S. , Abu Hashim M. F. , Junaedi S. , Sandu A. V. , Tahir M. F. M.

Archives of Metallurgy and Materials

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2022

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tom Vol. 67, iss. 1

261--267

EN

This study summarised the recent achievement in developing fiber reinforced geopolymer concrete. The factor of replacing Ordinary Portland Cement (OPC) which is due to the emission of carbon dioxide that pollutes the environment globally is well discussed. The introduction towards metakaolin is presented. Besides, the current research trend involved in geopolymer also has been reviewed for the current 20 years to study the interest of researchers over the world by year. Factors that contribute to the frequency of geopolymer research are carried out which are cost, design, and the practicality of the application for geopolymer concrete. Besides, the importance of steel fibers addition to the geopolymer concrete is also well discussed. The fundamental towards metakaolin has been introduced including the source of raw material, which is calcined kaolin, calcined temperature, chemical composition, geopolymerisation process, and other properties. Alkali activators which are mixing solution between sodium hydroxide (NaOH) and sodium silicate (Na2SiO3) have been reviewed. The mechanical properties of fibers reinforced metakaolin-based geopolymer concrete which is compressive and flexural are thoroughly reviewed. The compressive and flexural strength of fiber-reinforced metakaolin geopolymer concrete shows some improvement to the addition of steel fibers. The reviews in this field demonstrate that reinforcement of metakaolin geopolymer concrete by steel fibers shows improvement in mechanical performance.

13

Setting Time and Compressive Strength of Geopolymers Made of Three Indonesian Low Calcium Fly Ash with Variation of Sodium Silicate Addition

88%

Hidayati R. E. , Faradilla F. S. , Dadang D. , Harmelia L. , Nurlina N. , Prasetyoko D. , Fansuri H.

Archives of Metallurgy and Materials

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2021

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tom Vol. 66, iss. 4

1115--1121

EN

In this research, the effect of sodium silicate (Na2SiO3) on the geopolymerization of fly ash type F (low calcium) has been studied. the variations of Na2SiO3 used in the synthesized geopolymers were 19, 32, and 41wt%. the fly ash from three different power plant sources was characterized using X-Ray Fluorescence (XRF), X-Ray diffraction (XRD), Particle Size Analyzer (PSA), and Scanning Electron Microscopy (SEM). Fly ash-based geopolymers were tested for mechanical strength and setting time. The best geopolymer was obtained by adding 32% Na2SiO3, produced a compressive strength of 21.62 MPa with a setting time of 30 hours. Additions of 19wt% Na2SiO3 failed to form geopolymer paste while the addition of 41wt% Na2SiO3 decreased the mechanical strength of the geopolymer. Higher calcium content in low calcium fly ash produces stronger geopolymer and faster setting time.

14

Effect of Sodium Aluminate on the Fresh and Hardened Properties of Fly Ash-Based One-Part Geopolymer

88%

Ooi W.-E. , Liew Y. M. , Yong H. C. , Ho L.-N. , Al Bakri Abdullah M. M. , Ong S.-W. , Sandu A. V.

Archives of Metallurgy and Materials

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2022

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tom Vol. 67, iss. 2

441--445

EN

The one-part geopolymer binder was synthesis from the mixing of aluminosilicate material with solid alkali activators. The properties of one-part geopolymers vary according to the type and amount of solid alkali activators used. This paper presents the effect of various sodium metasilicate-to-sodium aluminate (NaAlO2/Na2SiO3) ratios on fly ash-based one-part geopolymer. The NaAlO2/Na2SiO3 ratios were set at 1.0 to 3.0. Setting time of fresh one-part geopolymer was examined through Vicat needle apparatus. Mechanical and microstructural properties of developed specimens were analysed after 28 days of curing in ambient condition. The study concluded that an increase in NaAlO2 content delayed the setting time of one-part geopolymer paste. The highest compressive strength was achieved at the NaAlO2/Na2SiO3 ratio of 2.5, which was 33.65 MPa. The microstructural analysis revealed a homogeneous structure at the optimum ratio. While the sodium aluminium silicate hydrate (N-A-S-H) and anorthite phases were detected from the XRD analysis.

15

A Potential Environmental Sustainability of Wood Ash in Normal and Geopolymer Concrete – A Review

88%

Nura Isa M. , Awang H. , Muthusamy K.

Advances in Science and Technology. Research Journal

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2023

|

tom Vol. 17, no 4

1--20

EN

The production of cement for concrete has led to the emission of carbon dioxide (CO₂) into the atmosphere, which has contributed to global warming. Moreover, the excessive amount of industrial waste from biomass energy production landfilled in our environments is continuously causing sustainability challenges. However, several studies were carried out to ascertain the possibilities of using these waste materials in concrete production to address the cement and waste disposal sustainable issues simultaneously. The present study reviewed multiple studies that were carried out on wood ash (WA) application in both normal and geopolymer concrete with an emphasis on fresh, hardened, and durability properties. WA effects as a pozzolanic material are summarized for its application in mortar/concrete production. WA can be used to replace cement in mortar/concrete at up to 20% replacement level, similarly, in geopolymer production, it was revealed that WA can be effectively utilized to replace ground granulated blast furnace slag (GGBS) or pulverized fly ash (PFA) at up to 50% replacement level. The sustainability impacts of WA utilization in concrete production were presented and discussed. Results of these findings revealed its suitability as supplementary cementitious material, but still there exists a gap in its utilization in geopolymer concrete.

16

Adhezja kompozytów geopolimerowych do betonu, stali i ceramiki

75%

Wala D. , Rosiek G.

Kompozyty

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2008

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tom R. 8, nr 1

36-40

PL

Oceniono wpływ temperatury na właściwości mechaniczne kompozytów geopolimerowych przeznaczonych do spajania różnych materiałów. Jako prekursor w badanych geopolimerach stosowano metakaolinit oraz popioły lotne z elektrowni Łaziska i Rybnik. Wypełniaczem były drobnoziarniste proszki o uziarnieniu poniżej 100 žm: mielony piasek, żelazo, chrom. Roztworem alkalizującym było szkło wodne z dodatkiem wodorotlenku sodu. Dla badanych kompozytów geopolimerowych oznaczono wytrzymałość na zginanie i ściskanie w zależności od temperatury wygrzewania. Najwyższą odporność termiczną i wzrost wytrzymałości na ściskanie ze wzrostem temperatury wykazał kompozyt zawierający jako prekursor równowagową mieszankę metakaolinitu i popiołu Łaziska oraz mielony piasek kwarcowy jako wypełniacz. Wszystkie badane kompozyty wykazały znaczny ubytek wytrzymałości na zginanie po wygrzaniu w 200°C, a następnie istotny wzrost po przetrzymaniu w temperaturze 400°C. Właściwości spajające badanych geopolimerów oceniano na podstawie pomiaru siły ścinającej w złączach ceramika-ceramika, metal-metal, metal-ceramika, beton-beton po przetrzymaniu w temp. 65, 400°C. Wszystkie badane złącza po wygrzaniu w temp. 65°C wykazują dobrą wytrzymałość na ścinanie, mieszczącą się dla rozwiązań optymalnych w zakresie 4,9+7,4 MPa. Po wygrzaniu w 400°C wytrzymałość na ścinanie tych złączy istotnie spada w najmniejszym stopniu dla połączeń ceramika-ceramika, w największym dla połączeń metal-ceramika.

EN

This paper analyses the influences of temperature on mechanical properties of geopolymer composites designed to joining various materials. Metakaolinite and fly ashes from the power plant "Łaziska" and "Rybnik" were applied as the precursor in studied geopolymers. Fine-grained powders about grain-size distribution < 100 žm (the milled sand and powder of the iron and chromium) were fillers. The alkalizing solution was the water glass (about module 3.3, density 1.38 g/cm3) with the addition of the sodium hydroxide. Six alkali activated mixture were prepared to investigation. For prepared geopolymer composites the bending and compressive strength depending on the curing temperature (65, 200, 400, 800°C were measured. The composite including as precursor equilibrium mixture of the metakaolinite and the flay ash (Łaziska) with precipitation the milled quartz sand as filler showed the highest thermal resistance and increase compressive strength with the growth of the temperature. All studied geopolymer composites showed the considerable decrease of the bending strength after heating at 200°C, and then essential increase after the curing at the temperature 400°C. The joining properties studied composites after the curing at 65 and 400°C was estimated by the measurement shear strength in joints: ceramics-ceramics, metal-metal, metal-ceramics, concrete-concrete. All studied joints after heating at 65°C show the shear strength within the range 4.9+7.4 MPa for optimum compositions. After heating at 400°C the shear strength of joints significance decreased, in the smallest rate for connections ceramics-ceramics and in the largest for connections the metal-ceramics.

17

Properties and Morphology of Fly Ash Based Alkali Activated Material (AAM) Paste Under Steam Curing Condition

75%

Razak R. A. , Izman S. N. S. S. , Abdullah M. M. A. B. , Yahya Z. , Abdullah A. , Mohamed R.

Archives of Metallurgy and Materials

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2023

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tom Vol. 68, iss. 2

785--789

EN

This paper details the properties, microstructures, and morphologies of the fly ash-based alkali-activated material (AAM), also known as geopolymers, under various steam curing temperatures. The steam curing temperature result in subsequent high strengths relative to average curing temperatures. However, detailed studies involving the use of steam curing for AAM remain scarce. The AAM paste was prepared by mixing fly ash with an alkali activator consisting of sodium silicate (Na2SiO3) and sodium hydroxide (NaOH). The sample was steam cured at 50°C, 60°C, 70°C, and 80°C, and the fresh paste was tested for its setting time. The sample also prepared for compressive strength, density, and water absorption testings. It was observed that the fastest time for the fly ash geopolymer to start hardening was at 80°C at only 10 minutes due to the elevated temperature quickening the hydration of the paste. The compressive strength of the AAM increased with increasing curing time from 3 days to 28 days. The AAM’s highest compressive strength was 61 MPa when the sample was steam cured at 50°C for 28 days. The density of AAM was determined to be ~2122 2187 kg/m3, while its water absorption was ~6.72-8.82%. The phase analyses showed the presence of quartz, srebrodolskite, fayalite, and hematite, which indirectly confirms Fe and Ca’s role in the hydration of AAM. The morphology of AAM steam-cured at 50°C showed small amounts of unreacted fly ash and a denser matrix, which resulted in high compressive strength.

18

Kierunki rozwoju spoiw mineralnych – geopolimerowe kompozyty budowlane

75%

Adamczewski A. , Woyciechowski P. , Seramowicz K.

Ochrona przed Korozją

|

2018

|

tom nr 3

57--61

PL

Współczesne kierunki rozwoju technologii spoiw mineralnych zorientowane są w szczególności na poszukiwanie materiałów o obniżonym negatywnym oddziaływaniu środowiskowym, przy zachowaniu parametrów użytkowych i trwałości. Powszechne podejście obejmuje modyfikację przez wprowadzanie tradycyjnych dodatków innych niż klinkierowe. Jednakże głównym kierunkiem rozwoju technologii spoiw pozostaje poszukiwanie nowych surowców o charakterystyce chemicznej podobnej jak w przypadku surowców klinkierowych, ale dotychczas nie stosowanych. W niniejszym artykule przedstawiono wybrane kierunki prowadzonych aktualnie badań w zakresie mineralnych spoiw budowlanych oraz wybrane zagadnienia związane z wytwarzaniem geopolimerowych spoiw mineralnych. Omówiono podstawowe właściwości użytkowe materiału geopolimerowego, a także perspektywy stosowania we współczesnym budownictwie.

EN

Contemporary trends in development of technology of mineral binders are oriented in particular to the search for materials with a reduced negative environmental impact, while obtaining not worsened performance characteristics and durability. A common approach includes modification by introducing conventional non-clinker additives. However the main direction of development of cement technology is the search for new materials of chemical base similar to clinker raw materials, but not yet used. This article presents selected trends of currently conducted research in the field of mineral building binders and selected topics related with geopolymer binders production. The basic properties of geopolymer binders and also the perspectives of its applications in building applications have been presented.

19

The performance of CFRP-strengthened heat-damaged metakaolin-based geopolymer concrete cylinders containing reclaimed asphalt aggregate

75%

Abadel A. A.

Materials Science Poland

|

2024

|

tom Vol. 42, No. 2

125--142

EN

Concrete structures are extremely vulnerable to fire damage, which greatly undermines their structural strength and durability. Recently, there has been a concerted effort to develop sustainable concrete materials. Geopolymer concrete (GPC) is a promising substitute for conventional cement concrete due to its use of recycled materials. However, despite the positive effect it has on the environment, GPC is susceptible to heat, which can cause it to deteriorate over time. In response to this issue, the use of carbon-fiber reinforced polymer (CFRP) has been proposed as a means of strengthening heat-damaged GPC. This study aims to investigate the effectiveness of CFRP-strengthened heat-damaged metakaolin-based GPC made from reclaimed asphalt pavement (RAP) aggregate. Three concrete mixtures were used, in which the conventional aggregate was substituted with RAP aggregate at 0%, 25%, and 50% replacement levels. In addition, the concrete cylinders were tested under ambient conditions and subjected to 300◦C. The results indicated that the substitution with 25% RAP aggregate significantly reduced compressive strength by 39.1%, while 50% replacement resulted in a 66.8% decrease compared with the control mixture. The use of CFRP sheets to strengthen heat-damaged GPC specimens was proven to be effective in increasing the resistance of the heated specimens and restoring the compressive strength and confinement energy to their original state before reaching the ultimate failure point. The use of CFRP sheets significantly increased compressive strengths, with increases ranging from 87.7% to 368.8% at 26◦C and 58.8% to 153.9% at 300◦C, compared with each mixture’s unstrengthened control specimen.

20

Problems of measuring the electrical parameters of geopolymer concretes

75%

Kozioł M. , Zygarlicki J. , Zmarzły D. , Janowska-Renkas E.

Przegląd Elektrotechniczny

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2022

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tom R. 98, nr 10

233--236

EN

The article presents the problems of measuring electrical parameters on the example of determining the resistivity of concrete samples. In addition, as part of the research work undertaken, a series of experimental measurements were carried out in the system of two electrodes on various samples of geopolymer concrete. The obtained results showed the need to improve the electrodes and subjecting to a detailed analysis of the contact connections between the electrodes and the sample in order to obtain a repeatable method of determining the resistivity of geopolymeric concrete samples.

PL

W artykule przedstawiono problematykę pomiarów parametrów elektrycznych na przykładzie wyznaczania rezystywności próbek betonowych. Ponadto w ramach podjętych prac badawczych, przeprowadzono serię pomiarów eksperymentalnych w układzie dwóch elektrod na różnych próbkach betonu geopolimerowego. Uzyskane rezultaty wykazały konieczność udoskonalenia elektrod i poddanie szczegółowej analizie połączeń stykowych pomiędzy elektrodami a próbką, celem uzyskania powtarzalnej metody wyznaczania rezystywności próbek betonów geopolimerowych.