There are many research devoted to the influence of carbon nanotubes (CNT) on the structure and properties of cement systems. In the course of this research, the combined influence of of multi-walled carbon nanotubes (MWCNT) and... more
There are many research devoted to the influence of carbon nanotubes (CNT) on the structure and properties of cement systems. In the course of this research, the combined influence of of multi-walled carbon nanotubes (MWCNT) and polycarboxylate (PCE) plasticizer on the products of hydration and the properties of hardened cement paste was investigated. The strength characteristics of nanomodified hardened cement paste and the hydration products were determined by the usage of modern methods of physico-mechanical and physico-chemical analyses. Based on the physico-chemical investigations, it was concluded the necessity of additional experiments, associated primary with questions of uniform distribution of the nanostructures and their chemical interactions with another components of admixture and cement system.
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Architectural concrete has wide opportunities to be used both for exteriors and interiors in different buildings. Architectural concrete is the type of concrete which is usually not subjected to finishing, therefore higher standards are... more
Architectural concrete has wide opportunities to be used both for exteriors and interiors in different buildings. Architectural concrete is the type of concrete which is usually not subjected to finishing, therefore higher standards are declared for its surface quality. According to normative documents, architectural concrete needs to have a uniform colour tone, texture, minimal defects and porosity of the surface. The present research demonstrates the concrete surface quality obtained in the course of varying different factors such as the presence of stabilizing admixture, granulometry of aggregates, usage of fly ash and workability of the concrete mixture. In the course of the research, the testing of raw materials and concrete in the fresh and hardened state were performed according to standard methodologies. The assessment of concrete surface quality was provided through the analysis of concrete surface photo 50x50 cm size. Based on the experimental results, it can be stated that better quality of the concrete surface was obtained in case of usage of gravel with two fractions of 4/16 and 2/8 and fly ash in the dosage of 25 % cement weight in the presence of plasticizing and stabilizing admixtures. The concrete mixture with high workability showed better filling of formwork and mixture particles packing on the formwork surface which led to a better quality of the concrete surface.
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AbstractThe rheological properties of concrete mixtures are presently important when new technologies for transporting, handling, placing, and compacting concrete are used in new concrete construct...
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The article aims to present a research into the impact of the dosage and effectiveness of superplasticizers based on modified acrylic polymer and polycarboxylate ester (from 0 to 1.2 %) on rheological properties of the cement pastes... more
The article aims to present a research into the impact of the dosage and effectiveness of superplasticizers based on modified acrylic polymer and polycarboxylate ester (from 0 to 1.2 %) on rheological properties of the cement pastes (yield stresses and plastic viscosities), of different testing times after mixing (from 0 to 90 min). Materials used in the study: Portland cement CEM I 42.5 R, superplasticizers SP1 (modified acrylic polymer based), SP2 (polycarboxylate ester based), and water. Investigation was carried out using rotational rheometer Rheotest RN4.1 with coaxial cylinders. The tests revealed that superplasticizer SP2 is more effective than SP1 – cement paste (W/C = 0.30) exhibits better flowability and improved rheological qualities. Superplasticizers SP1 and SP2 exhibit different levels of plasticizing effectiveness and ability to retain the effect’s duration. Due to the increase in the dosage of superplasticizers SP1 and SP2 from 0 to 1.2 %, plasticizing effect increases. It is also observed that larger dosage of SP1 (0.6-1.2 %) results in slower increase in plasticizing effects until the 90 min margin. In conclusion, from the start of mixing until the 90 min margin, the best plasticizing effect and its retention achieved by superplasticizer SP2. Recommended SP2 dosage – from 0.6 to 0.8 %.
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The influence of concentration of cement particles φc on rheological behavior (flow behavior, dynamic yield stress, plastic viscosity) and thixotropy of the Portland cement CEM I 42.5 R paste was investigated in this research. Also,... more
The influence of concentration of cement particles φc on rheological behavior (flow behavior, dynamic yield stress, plastic viscosity) and thixotropy of the Portland cement CEM I 42.5 R paste was investigated in this research. Also, thixotropy was evaluated by index of reversible structure of Portland cement paste. Concentration of cement particles φc ranged from 0.434 to 0.518. Investigation was carried out using rotational rheometer Rheotest RN4.1 with coaxial cylinders. The tests revealed that as φc decreases from 0.518 to 0.434, rheological behavior of Portland cement paste is improved: yield stress decreases from 12.7 Pa to 7.1 Pa as well as plastic viscosity – from 4.3 Pa·s to 0.88 Pa·s. The exponential correlation between φc and index of reversible structure of Portland cement paste was found. As φc decreases from 0.518 to 0.434, index of reversible structure of Portland cement paste, which describes a thixotropy, decreases from 5291 Pa·min to 977 Pa·min.
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Abstract The article analysis the effect of synthetic zeolite on properties of concrete mix and hardened concrete. Zeolite was obtained from waste of aluminum fluoride production by low-temperature synthesis and added in concrete mix up... more
Abstract The article analysis the effect of synthetic zeolite on properties of concrete mix and hardened concrete. Zeolite was obtained from waste of aluminum fluoride production by low-temperature synthesis and added in concrete mix up to 10% as Portland cement replacing admixture. Test results revealed that, replacing cement by synthetic zeolite considerably decreases concrete scaling during freezing and thawing cycles. Compressive strength, density of concrete and water absorption were measured. The test results proved that synthetic zeolite obtained from aluminum fluoride by means of low temperature synthesis can be used as a supplementary cementitious material to increase the durability of concrete.
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The compositions and technological parameters of obtaining filtering corundum and quartz ceramic materials with functional membrane coatings obtained in the Al2O3–ZnO, Al2O3–Fe2O3, Al2O3–CuO and Al2O3–MnO2 systems were developed; the... more
The compositions and technological parameters of obtaining filtering corundum and quartz ceramic materials with functional membrane coatings obtained in the Al2O3–ZnO, Al2O3–Fe2O3, Al2O3–CuO and Al2O3–MnO2 systems were developed; the regularities of the process of formation of a layered porous permeable structure have been established in conjunction with the physicochemical properties, phase composition and performance characteristics of filter materials. Scientifically substantiated and experimentally confirmed the desirability of the use of polyphenylsiloxanes as a binder to obtain porous permeable corundum and quartz ceramics
Hydration of cement systems modified by nano additives requires the understanding of its mechanisms. The present research is focused on the investigation of hydration processes in cement pastes modified by multi-walled carbon nanotubes... more
Hydration of cement systems modified by nano additives requires the understanding of its mechanisms. The present research is focused on the investigation of hydration processes in cement pastes modified by multi-walled carbon nanotubes (MWCNTs) suspension. The ultrasonication method was used for homogenization of MWCNTs in the volume of an aqueous suspension. The hydration of cement pastes was assessed by the calorimetry test. The prolongation of cement hydration in case of modification by MWCNT suspension was observed. The microstructure observation by scanning electron microscopy (SEM) was performed for identification of MWCNT's dispergation in hardened cement pastes and for the observation of cement hydration products. The compressive and flexural strength were tested to evaluate the effect of MWCNT on mechanical properties of hardened cement paste.
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Calcium nitrate in mortars and concrete is used as a multifunctional additive: as set accelerator, plasticizer, long term strength enhancer and as antifreeze admixture. Used binding material and the amount of calcium nitrate, affect the... more
Calcium nitrate in mortars and concrete is used as a multifunctional additive: as set accelerator, plasticizer, long term strength enhancer and as antifreeze admixture. Used binding material and the amount of calcium nitrate, affect the characteristics of the concrete mixture and strength of hardened concrete. The setting time of the initial and the final binding at different temperatures of hardening (+ 20 °C and + 5 °C) of the pastes made of different cements (Portland cement CEM I 42.5 R and Portland limestone cement CEM II/A-LL 42.5 R) and various amounts of calcium nitrate from 1 % until 3 % were investigated. The effect of calcium nitrate on technological characteristics of concrete mixture (the consistency of the mixture, the density, and the amount of air in the mixture), on early concrete strength after 2 and 7 days, as well as on standard concrete strength after 28 days at different temperatures (at + 20 °C and + 5 °C) were analysed.
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Concrete is a composite material composed of a binder, aggregates, water and additives. Mixing of cement with water results in a number of chemical reactions known as cement hydration. Heating of concrete results in dehydration processes... more
Concrete is a composite material composed of a binder, aggregates, water and additives. Mixing of cement with water results in a number of chemical reactions known as cement hydration. Heating of concrete results in dehydration processes of cement minerals and new hydration products, which disintegrate the microstructure of concrete. This article reviews results of research conducted with Portland and alumina cement with conventional and refractory concrete aggregates. In civic buildings such common fillers as gravel, granite, dolomite or expanded clay are usually used. It is important to point out the differences between fillers because they constitute the majority of the concrete volume.
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Hydraulic concrete is a composite material that consists of coarse and fine aggregates and a binder, which transforms from liquid to solid state while curing and is exposed to destructive impacts during exploitation. The research was... more
Hydraulic concrete is a composite material that consists of coarse and fine aggregates and a binder, which transforms from liquid to solid state while curing and is exposed to destructive impacts during exploitation. The research was carried out with various cements – Portland cement, slag Portland cement, slag cement and limestone. The results of research showed that quantity of slag in hardened Portland cement paste influences freezing-thawing of concrete for hydraulic structures. Hydraulic concrete under impact of the Baltic Sea is influenced by sea water and freezing and thawing cycles. Under the mentioned impacts exerted simultaneously, experiment results enable assessment of durability of hydraulic concrete. The objective of the work is to assess the impact of the environment of the Baltic Sea on changes in properties of hydraulic concrete after cyclic freezing and thawing.
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Abstract The article analysis the effect of synthetic zeolite on properties of concrete mix and hardened concrete. Zeolite was obtained from waste of aluminum fluoride production by low-temperature synthesis and added in concrete mix up... more
Abstract The article analysis the effect of synthetic zeolite on properties of concrete mix and hardened concrete. Zeolite was obtained from waste of aluminum fluoride production by low-temperature synthesis and added in concrete mix up to 10% as Portland cement replacing admixture. Test results revealed that, replacing cement by synthetic zeolite considerably decreases concrete scaling during freezing and thawing cycles. Compressive strength, density of concrete and water absorption were measured. The test results proved that synthetic zeolite obtained from aluminum fluoride by means of low temperature synthesis can be used as a supplementary cementitious material to increase the durability of concrete.
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Knygoje nagrinėjami statybinių medžiagų ir dirbinių gamybos technologiniai procesai ir jiems vykdyti naudojami technologiniai įrenginiai. Pateikiamos įvairių įrenginių schemos, aprašomi jų veikimo principai. Apžvelgiami statybinių... more
Knygoje nagrinėjami statybinių medžiagų ir dirbinių gamybos technologiniai procesai ir jiems vykdyti naudojami technologiniai įrenginiai. Pateikiamos įvairių įrenginių schemos, aprašomi jų veikimo principai. Apžvelgiami statybinių medžiagų pagrindiniai gamybos procesai, jų klasifikavimas, nagrinėjami mechaniniai, hidromechaniniai statybinių medžiagų bei dirbinių gamybos procesai, aprašomi šiluminiai statybinių medžiagų bei dirbinių gamybos procesai (šildymas, aušinimas), supažindinama su masės kaitos gamybos procesais (džiovinimas, absorbcija ir kt.) ir jiems vykti naudojamais įrenginiais. Pateikiama džiovyklų klasifikacija, schemos, jų panaudojimo galimybės. Leidinys skirtas aukštųjų mokyklų studentams, studijuojantiems statybos inžinerijos disciplinas, taip pat projektuotojams, statybinių medžiagų gamintojams bei jų naudotojams
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The goal of the study was to determine the effect of waste tire cord yarn with attached rubber particles on the properties of concrete made of different types of cement (Portland cement without additives – CEM I, Portland cement with... more
The goal of the study was to determine the effect of waste tire cord yarn with attached rubber particles on the properties of concrete made of different types of cement (Portland cement without additives – CEM I, Portland cement with limestone additive – CEM II). The filament waste (added at 0%, 2%, 4%, 6%, 8%, and 10% of the amount of fine aggregate) is water absorbing textile fibre additive with rubber particles, therefore a bigger amount of water is required to prepare the concrete mixture. With waste additive, the density and compressive strength of concrete reduces, but water absorption increases. The forecasted freeze-thaw resistance of concrete with cement type CEM I and recycled tire cord increases and slightly reduces when cement type CEM II is used, however retains similar resistance in about 1000 freeze-thaw cycles. The coefficient of thermal conductivity decreases approx. 35%, when 10% of recycled tire textile cord is added to concrete mixture.
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The nanoparticles and nanostructures such as nano silica, nano metakaolin, titanium dioxide and aluminium oxide nanoparticles, graphite nanomaterials, carbon nanotubes are used for modification of composite materials in construction... more
The nanoparticles and nanostructures such as nano silica, nano metakaolin, titanium dioxide and aluminium oxide nanoparticles, graphite nanomaterials, carbon nanotubes are used for modification of composite materials in construction industry. The considerable attention of researchers is focused on the investigation of cement systems modified by carbon nanotubes (CNT). The present research describes the generalized data about modification of cement systems by CNT suspension in fresh and hardened state. The influence of carbon nanotubes on setting time of cement paste, rheological and mechanical properties of nanomodified cement systems are demonstrated in the present research.
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The study investigates effect of the additive consisting of natural zeolite (clinoptilolite) and soda lime glass powder on the hydration, mechanical properties and porosity of Portland cement concrete. The effect of mineral additive on... more
The study investigates effect of the additive consisting of natural zeolite (clinoptilolite) and soda lime glass powder on the hydration, mechanical properties and porosity of Portland cement concrete. The effect of mineral additive on the technological, physical-mechanical properties and porosity of the mortar was investigated by increasing the content of natural zeolite and glass powder added to the mortar up to 20% by weight of cement in increments of 5% and different particles size of natural zeolite. The mixes with the best technological and mechanical properties were identified and further studies were conducted by replacing 10% and 15% of cement with natural zeolite and soda lime glass with an average grain size of 59.3 μm, 29.0 μm or 3.6 μm of zeolite, and 29.6 μm of glass powder. The hydration process and microstructure of hardened cement paste modified with the aforementioned mineral additives was analysed by microcalorimetry, X-ray diffraction tests and thermogravimetric ...
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Frost resistance is one of the key indicators of concrete quality. Frost resistance can be determined by direct testing; however it is time-consuming and labour-intensive method. Concrete decomposition is a complex process (from initial... more
Frost resistance is one of the key indicators of concrete quality. Frost resistance can be determined by direct testing; however it is time-consuming and labour-intensive method. Concrete decomposition is a complex process (from initial signs of degradation to complete failure of the surface subjected to freezing) involving many factors. Frost resistance of concrete can be predicted from porosity parameters after determining their relation to frost resistance. Test results showed the relation between the closed porosity of concrete and frost resistance factor. Closed porosity of concrete was found to have a significant influence on frost resistance factor. It is shown that closed porosity depends on the concentration of coarse aggregate in concrete, the closed porosity and predicted frost resistance of concrete increase with lower concentration of coarse aggregate.http://dx.doi.org/10.5755/j01.ms.17.2.493
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Cement slurries and concrete mixtures have dilatant behaviour in their flow. This has negative influence on the mixtures transportation by concrete pumps. Therefore, it is important to know the factors that have effect on the mixtures... more
Cement slurries and concrete mixtures have dilatant behaviour in their flow. This has negative influence on the mixtures transportation by concrete pumps. Therefore, it is important to know the factors that have effect on the mixtures dilatancy. The influence of microsilica and plasticizing admixtures on mixtures dilatancy is investigated in this work. Rheological properties of the mixtures were tested with a rotating viscometer with coaxial cylinders. Two indexes of mixtures dilatancy were evaluated as well investigation results of show that microsilica additives increase yield stress of cement slurry and reduce its viscosity and greatly reduce dilatancy of cement slurry due to its particles fineness and its spherical shape. Microsilica suspension with complex used with plasticizing admixtures has different effect on the dilatancy depending on chemical composition of admixture. Keywords: cement, microsilica, slurry, yield stress, viscosity, viscometer, dilatancy.
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The influence of a complex application of both plasticizing and air-entraining effects on concrete with polycarboxylate ether superplasticizer (PCE), air-entraining admixture (AIR), or an anti-foaming agent (AF) is analyzed in this paper... more
The influence of a complex application of both plasticizing and air-entraining effects on concrete with polycarboxylate ether superplasticizer (PCE), air-entraining admixture (AIR), or an anti-foaming agent (AF) is analyzed in this paper with considerations for on the air content, workability, flexural and compressive strength, and freezing–thawing resistance of hardened cement mixtures. The effect of the complex behavior of PCE, AIR, and AF on the porosity of hardened cement mortar (HCM) and freezing–thawing resistance was investigated; freezing–thawing resistance prediction methodology for plasticized mortar was also evaluated. The results presented in the article demonstrate the beneficial influence of entrained air content on consistency and stability of cement mortar, closed porosity, and durability of concrete. Freezing–thawing factor KF depending on porosity parameters can be used for freezing–thawing resistance prediction. With both plasticizing (decrease in the water–cement...
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The present research is focused on the investigation of the influence of ultrafine additives on the structure formation of hardened cement paste and the establishment of the mechanisms of the morphological transformations, which determine... more
The present research is focused on the investigation of the influence of ultrafine additives on the structure formation of hardened cement paste and the establishment of the mechanisms of the morphological transformations, which determine the properties of hydrated products. In the course of the research, the modification of ordinary Portland cement was performed by the suspension of multi-walled carbon nanotubes (MWCNTs), carbon black (CB) paste, and silica fume (SF). Scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) microanalysis, X-ray diffraction (XRD) analysis, thermal analysis, and Fourier-transform infrared (FTIR) spectroscopy were used to study cement hydration products. The morphology of hardened cement paste depends on the chemical reactivity of additives, their geometry, and their genesis. The action mechanism of the inert carbon-based additives and pozzolanic silica fume were considered. The cement hydration products formed in the process of modification ...
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Modification of cement pastes by MWCNT (multi-walled carbon nanotubes) suspension enables to manage by their rheological properties due to the nanometer size of MWCNT. Dispersity degree of MWCNT suspension may be determined by the number... more
Modification of cement pastes by MWCNT (multi-walled carbon nanotubes) suspension enables to manage by their rheological properties due to the nanometer size of MWCNT. Dispersity degree of MWCNT suspension may be determined by the number of factors such as type and intensity of homogenization equipment, duration of homogenization and some other. The aim of present research consists in the establishment of optimal methodology of MWCNT suspension homogenization and investigation of dependence between dispersity degree of MWCNT suspension and rheological properties of cement pastes with that suspension. Two types of homogenization methods of MWCNT were tested such as ultrasonication and homogenization based on rotor-stator principle. The ultrasonication treatment about 6 min was established as optimal homogenization technique in the course of the current research. The yield stress and plastic viscosity of cement paste modified by MWCNT suspension increased in comparison with cement pas...
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Abstract Complex nanodispersed systems with multi-walled carbon nanotubes and nanodispersed silica have a significant impact on the processes of hydration, setting and hardening of construction composites with Portland cement binder... more
Abstract Complex nanodispersed systems with multi-walled carbon nanotubes and nanodispersed silica have a significant impact on the processes of hydration, setting and hardening of construction composites with Portland cement binder predetermining their durability. The main effect of the modification of cement matrix in the case of adding complex nanodisperse systems is provided by the directed influence on the processes of hydration and subsequent crystallization of new products in hardened cement paste. The effect of the addition of the carbon nanotubes is analyzed and quantified by inspecting in each case one sample with nanotubes and one without by the help of a nanoindenter and another scanning electron microscope. Carbon nanotube dispersion and nanosized silica being added, the binding matrix is forming a perfect dense shell from crystalline hydrates on the surface of solid phase that provides strong binding matrix in cement concrete.
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This research article analyzes the synthetic zeolite is produced from the waste of AIF3 (amorphous SiO2), NaOH and Al(OH)3 by low-temperature (105 °C) synthesis and modified with CaCl2. The modified zeolite influence on freeze–thaw and... more
This research article analyzes the synthetic zeolite is produced from the waste of AIF3 (amorphous SiO2), NaOH and Al(OH)3 by low-temperature (105 °C) synthesis and modified with CaCl2. The modified zeolite influence on freeze–thaw and de-icing salt resistance of the hardened cement paste was tested with the replacement of 5% and 10% of the cement mass in the concrete by the zeolite additive. The specimens with 3% NaCl solution on the top surface were tested by one-sided freeze–thaw cycles. The scaled material content, the elongation of specimens and the ultrasonic pulse velocity were tested after every 7 cycles of freeze–thaw. Internal and surface X-ray diffraction patterns were obtained and analysed. The results of the investigation indicated significant improvement of freeze–thaw and de-icing salt resistance of the hardened cement paste. High freeze–thaw with de-icing salt resistance was obtained by changes in the microstructure of the modified cement paste and cement hydration p...
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Concrete is widely used in the structures of bridges, flyovers, sidewalks and carriageways that are exposed to freeze-thaw cycles in wet conditions and are treated with de-icing salts. Tests were made to examine the effect of sodium... more
Concrete is widely used in the structures of bridges, flyovers, sidewalks and carriageways that are exposed to freeze-thaw cycles in wet conditions and are treated with de-icing salts. Tests were made to examine the effect of sodium silicate solution on the resistance of hardened cement paste to frost and de-icing salts. 5% sodium chloride, calcium chloride and manganese chloride solutions were used as de-icing salts. The deterioration of hardened cement paste was assessed by the changes in compressive strength, ultrasonic pulse velocity, specimen deformations and amount of scaled matter during cyclic freezing and thawing. Test results have revealed that hardened cement paste modified with sodium silicate solution is less subject to destruction when the surface of cement paste is treated with de-icing salt solutions under cyclic freeze-thaw conditions. The research has proved that sodium silicate solution increases the durability of concrete used in road structures.
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3D concrete printing is a perspective technology for sustainable construction and realization of sophisticated architectural projects. The current research proposes the thermal engineering calculation of wall structure based on the 3D... more
3D concrete printing is a perspective technology for sustainable construction and realization of sophisticated architectural projects. The current research proposes the thermal engineering calculation of wall structure based on the 3D printed concrete element of a total thickness of 150 mm with the internal air layer about 75 mm. The 3D printing mixture was designed with the addition of perlite as filler in the dosage of 8 % by weight of cement. The printing process was performed by the 3D printer of Contour Crafting type through the nozzle with a size of 20 mm. The thermal engineering calculation was implemented for the A++ energy consumption class. The wall structure based on the 3D printed concrete element with perlit has the thermal resistance comparable with one for wall structures based on brick and aerated concrete. The total thickness of the designed wall structure with 3D printed concrete element decreased by 100 mm and 50 mm in comparison with wall structures based on bric...
The influence of different types of aggregates and W/C ratio on concrete properties is analysed. In order to achieve this aim, lightweight (with expanded clay aggregate) and normal concrete (with gravel aggregate) mixtures are prepared... more
The influence of different types of aggregates and W/C ratio on concrete properties is analysed. In order to achieve this aim, lightweight (with expanded clay aggregate) and normal concrete (with gravel aggregate) mixtures are prepared with different W/C ratios. Different W/C ratios are selected by reducing the amount of cement when the amount of water is constant. The following properties of concrete have been determined: density, compressive strength and water absorption. Additionally, the statistical data analysis is performed and influence of aggregate type and W/C ratio on concrete properties is determined. The empirical equations indicating dependence between concrete strength and W/C and strength of aggregate are obtained for normal concrete and light-weight concrete.
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In this study, the rheological properties of cement paste modified by a suspension containing both multi-walled carbon nanotubes (MWCNT) and carboxymethyl cellulose (CMC) (MWCNT/CMC suspension) with different types of plasticising... more
In this study, the rheological properties of cement paste modified by a suspension containing both multi-walled carbon nanotubes (MWCNT) and carboxymethyl cellulose (CMC) (MWCNT/CMC suspension) with different types of plasticising admixtures (Pl), such as lignosulphonate (LS), sulfonated naphthalene formaldehyde condensate (NF), and polycarboxylate ether (PCE) were evaluated. The increase in yield stress and plastic viscosity up to 20% was established in the case of the modification of cement-based mixtures by MWCNT in the dosage up to 0.24% by weight of cement (bwoc) without Pl and with LS and NF. The complex modification of cement paste by MWCNT and PCE increases the yield stress and plastic viscosity from the MWCNT dosage of 0.06% and 0.015% bwoc, respectively. The yield stress and plastic viscosity of cement paste with PCE enhanced by 265% and 107%, respectively, in a MWCNT dosage of 0.12% bwoc. MWCNT do not have a significant influence on the flow behaviour index of cement past...
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Individual multi-walled carbon nanotubes were investigated for their usefulness as nanoscale electrochemical electrodes. The nanotubes were mounted on metal-coated atomic force microscopy tips, and the assembly was insulated with Parylene... more
Individual multi-walled carbon nanotubes were investigated for their usefulness as nanoscale electrochemical electrodes. The nanotubes were mounted on metal-coated atomic force microscopy tips, and the assembly was insulated with Parylene polymer. Approximately 200nm of the nanotube tip was exposed by use of a laser so the entire probe could be immersed in an electrolytic solution with only the nanotube tip