This review highlights the effects of adding to asphalt binder and asphalt mixtures, emphasizing its growing adoption globally due to environmental and economic advantages. The analysis evaluates the performance of asphalt binders and concrete mixtures modified with different forms of polyethylene (PE), including low-density polyethylene (LDPE) and high-density polyethylene (HDPE). The review revealed that incorporating waste polyethylene significantly enhances key properties of asphalt mixtures. Specifically, PE addition increases the softening point, viscosity, and specific gravity while reducing penetration. Furthermore, it improves the complex shear modulus, thermal stability, moisture resistance, and resistance to permanent deformation, although it may lead to a decrease in bulk density and creep rate of modified mixtures. The optimal PE content is recommended to be in the range of 4–12% by weight of binder, yielding substantial improvements in Marshall stability, flow, voids in mineral aggregates (VMA), air voids, dynamic modulus, and overall strength.
The primary objective of the study was to conduct mechanical, dynamic, thermal, and rheological analyses of composites based on PLA/PHBV blends. Specifically, three composites were produced with microcrystalline cellulose content at 5, 10, and 15wt.%. These materials were also subjected to aging tests. The findings of the study reveal the strengthening effect of microcrystalline cellulose and its positive impact on resistance to environmental factors. However, it is important to note that an excessive amount of filler decrease strength properties and processing issues. Despite this limitation, the study demonstrates the significant potential for using microcellulose and biodegradable PLA/PHBV blends to create high-strength, environmentally friendly polymer composites.
Wykonano badania reometryczne polimerowego kompozytu drzewnego na osnowie polipropylenu (PP) oraz opracowano jego charakterystyki reologiczne, wyznaczając parametry równania Kleina i równania Ostwalda i de Waele’a. Wykonano badania symulacyjne procesu wytłaczania celem dokonania oceny zastosowanych modeli reologicznych. Stwierdzono, że można uzyskać dobre wyniki modelowania procesu wytłaczania przy zastosowaniu stosunkowo prostego modelu reologicznego Ostwalda i de Waele’a. W przypadku tego modelu dostępne bazy materiałowe dostarczają znacznie więcej danych, niż w przypadku modelu Kleina.
EN
Rheometric studies of a polypropylene-based wood plastic composite were performed and its rheological characteristics were developed by determining the parameters of the Klein and Ostwald-de Waele equations. Simulation studies of the extrusion process were performed to evaluate the applied rheological models. Good results for modeling the extrusion process were obtained by using a relatively simple Ostwald-de Waele rheological model. For this model, the available material databases provide much more data than for the Klein model.
The structure and size of droplets of the inner phase of a multiple emulsion and rheological properties of the produced multiple emulsion are presented in this paper. The multiple emulsion was produced in a stirred vessel equipped with four baffles. In the study, two different stirrers: turbine impeller and Rushton turbine impeller were used. The liquids used in the produced multiple emulsion were: distilled water and refined sunflower oil. 8 g and 16 g lecithin from soya beans were used as an emulsifier. The preparation time was respectively 15 min. and 45 min. The structure of the obtained emulsions is presented in the form of photos taken with the diagnostic inverted microscope. The results size of droplets were presented in the form of graphics as a distribution of drops. The rheological properties of the multiple emulsion were presented graphically and it was described using the rheological model.
Thermo-mechanical devulcanization process of ground tire rubber (GTR) in a planetary extruder was investigated. The rheological properties of reclaimed rubber (rGTR) were studied using a Mooney viscometer and a rubber processing analyzer (RPA). Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) were used to determine reclaimed rubber structure. Increasing the scale of the devulcanization process (from 0.5 to 4 kg/h) resulted in a deterioration of the processing properties, which in the case of partially devulcanized rubber can only be determined using an RPA rheometer.
PL
Zbadano proces termo-mechanicznej dewulkanizacji zmielonych opon samochodowych (GTR) w wytłaczarce planetarnej. Właściwości reologiczne regeneratu gumowego (rGTR) oznaczono za pomocą wiskozymetru Mooney’a i reometru bezrotorowego (RPA). Do oceny struktury regeneratu gumowego stosowano spektroskopię w podczerwieni z transformacją Fouriera (FT-IR) i skaningową mikroskopię elektronową (SEM). Zwiększanie skali procesu dewulkanizacji (z 0,5 do 4 kg/h) skutkowało pogorszeniem właściwości przetwórczych rGTR, które w przypadku częściowo zdewulkanizowanej gumy można oznaczyć jedynie za pomocą reometru RPA.
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Biomass-derived biochar has gained significant attention due to its unique properties and potential applications in various fields, including asphalt pavement engineering. However, there has been no comprehensive review to date that systematically examines the state-of-theart research on biochar utilization in asphalt pavements, identifies the key knowledge gaps, and provides recommendations for future research directions. This review aims to fill this gap by providing a novel and critical analysis of the sources and production methods of biochar, the techniques for modifying and characterizing its properties, and its recent applications as an asphalt binder modifier, asphalt mixture additive, and stormwater filter material. The review employs a systematic literature search and analysis methodology, using scientific databases such as Web of Science and Scopus, and keywords related to biochar, asphalt, pavement, and environmental and economic aspects. The selected studies are reviewed and synthesized to identify research gaps, challenges, and future directions, with a focus on the technical, environmental, and economic feasibility of biochar utilization in asphalt pavements. The review also examines the life cycle assessment, carbon sequestration potential, and cost-benefit analysis of biochar utilization. The novelty of this review lies in its holistic approach to assessing state-of-the-art knowledge and its identification of key research needs and opportunities for advancing this emerging field. The review aims to provide valuable insights and recommendations for researchers, practitioners, and policymakers interested in leveraging the benefits of biochar for sustainable and high-performance asphalt pavements.
The work aim is to investigate the rheological and mechanical behavior of eco-friendly mortar made with marble powder. Marble have used as sand by total substitution of natural sand and as additional materials by partial substitution of cement. Firstly, rheological tests were carried out on the cement pastes in order to studying the effect of cement substitution by marble powder on the rheological behavior. Secondly, our study is devoted to evaluate the mechanical performances (flexural strength, compressive strength, mechanical behavior and ultrasonic pulse velocity) of a fluid mortar such as the case of the self-compacting mortars elaborated with the marble powder as addition materials and as a sand. The mechanical test results show that a significantly improved of compressive strength and mechanical behavior of an ecological cement mortar made with marble waste as a natural sand. However, marble-based mortars with 100% of marble sand have given a mechanical strength similar to that obtained by control cement mortar (100% natural sand). It was also noted that it can be obtained an ecological cement mortar made with 30% of marble powder as an addition supplementary materials. This leads to a reduction in cement consumption cad a reduction in CO2 gas emissions caused by cement production.
The rheological properties of fresh mortars and self-compacting concretes (SCC) at rest – the static yield value gs and the thixotropy factor AT – at temperatures from 10 to 30°C were investigated. The static yield value gs and the thixotropy factor AT of SCC depends on the temperature and the w/c ratio. Immediately after casting, the static yield value gs of the SCC is the higher the higher the temperature and/or w/c ratio are. Thixotropy factor AT of fresh SCC depends mainly on w/c ratio – the higher w/c ratio the lower AT is. The increase in temperature of SCC reduces thixotropy factor AT, but the effect is insignificant. During the 40 minutes that the SCC remain at rest, the static yield value gs increases and this increase is faster for mixes with a higher w/c ratio. Thixotropy factor AT of SCC left in rest first increases over time, but then, after just 20 to 40 minutes, begins to decrease. Temperature does not affect static yield value gs and thixotropy factor AT changes in time. The nature of the effect of temperature on the rheological properties of mortars and SCC is analogous. It was proven that model mortars can be used to predict the effect of temperature on the rheological properties of SCC both in the flow phase and at rest and to predict changes in these parameters over time. The implications of the temperature effect on the rheological properties of SCC in terms of formwork pressure were also discussed.
PL
Celem badań było określenie wpływu temperatury i czasu na parametry reologiczne mieszanek BSZ w stanie spoczynku – statyczną granicę płynięcia gs i współczynnik tiksotropii AT. Dodatkowo zweryfikowano możliwość wykorzystania badań reologicznych wykonanych na zaprawach modelowych do przewidywania wpływu temperatury na parametry reologiczne mieszanki BSZ w stanie spoczynku. Stwierdzono, że zmieniająca się w zakresie od 10 do 30°C temperatura istotnie wpływa na statyczną granicę płynięcia gs mieszanki BSZ w stanie spoczynku. Im temperatura mieszanki jest wyższa, tym statyczna granica płynięcia gs mieszanki jest większa i szybciej wzrasta w czasie. Wzrost statycznej granicy płynięcia w czasie wynika najpierw z samozagęszczenia mieszanki BSZ, a następnie z postępującego procesu hydratacji i utraty efektu działania SP. Statyczna granica płynięcia gs jest znacznie, nawet o rząd wielkości większa od dynamicznej granicy płynięcia. Współczynnik tiksotropii AT maleje ze wzrostem temperatury, przy czym wpływ temperatury na współczynnik tiksotropii AT nie jest istotny w porównaniu do wpływu w/c. Wykazano, że charakter wpływu temperatury na właściwości reologiczne zapraw modelowych i mieszanek BSZ w spoczynku jest analogiczny. Zaprawy modelowe mogą być wykorzystywane do prognozowania wpływu temperatury na właściwości reologiczne mieszanki BSZ w stanie spoczynku. Wyznaczono zależności liniowe pomiędzy parametrami reologicznymi zapraw i mieszanek betonowych w stanie spoczynku. Przedyskutowano mechanizm wpływu temperatury na właściwości reologiczne mieszanki BSZ w stanie spoczynku w aspekcie ich wpływu na parcia na deskowania. W wyższej temperaturze mieszanka BSZ charakteryzuje się większą statyczną granicą płynięcia gs i szybszym jej wzrostem, co powoduje, że parcie mieszanki BSZ na deskowania tym mniejsze, im większa jest jej temperatura.
With the rapid development of the construction industry and higher requirements on the properties of materials, extensive studies have been made to improve the property of the concrete and cementitious materials. This paper mainly studies the mechanical property, anti-chlorine ion diffusion, anti-chlorine ion diffusion, anti-freezing performance, hydration process, microstructure and rheological property of the concrete and cementitious materials after adding cellulose nanofibers. Results showed that the compressive strength of C40 concrete with 0.15% cellulose nanofibers added was 75.72 MPa at 56 days of age, 23.11% higher than that of the control group. It was also higher than that of concrete with 0.20% cellulose nanofibers admixture added. When the content of cellulose nanofibers was 0.15%, the flexural strength reached the maximum value of 6.55 MPa, improving by 24% compared with the control group. Under the circumstances of 150 freeze-thaw cycles, the mass loss rate of C50 concrete with 0.15% CNFs admixture registered at 0.41%, reducing by 0.81% compared with the control group. However, when the cellulose nanofibers increased to 0.20%, the mass loss rate of the concrete reached 0.48%, indicating that adding an appropriate amount of cellulose nanofibers could improve the performance of the concrete. The study provides a strong scientific basis for modifying concrete and cementitious materials.
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The technological parameters of 3D printing have an influence on the mechanical properties of the manufactured components. The purpose of the article was to study the comparative influence of the technological parameter of the number of shells variable in two stages (2 and 10) on selected mechanical properties. The maximum tensile stress for the number of shells 10 was 39.80 MPa, which is higher compared to the number of shells 2: 30.98 MPa. In the case of the maximum bending stress for the number of shells 10, an average value of 61.02 MPa was obtained, which is higher compared to the number of shells of 2: 37.46 MPa. Furthermore strong fit of the Kelvin-Voight model was obtained, as confirmed by the values of the 𝐶ℎ𝑖2:0.0001 and 𝑅2:0.997 coefficients.
W artykule dokonano ogólnej charakterystyki sposobu wytwarzania tuszów spożywczych stosowanych do drukowania żywności w 3D. Wskazano, że obecnie do produkcji tuszów spożywczych, które muszą spełniać ściśle określone właściwości reologiczne, używana jest ograniczona liczba składników. Przy czym ciągle testowane są nowe komponenty i układy spożywcze, jak również optymalizowane są parametry techniczne drukarek 3D. Szczególnie dobrą przydatność do druku wykazują makroskopowo jednorodne układy żelowe i emulsyjne o wysokiej tiksotropii, zawierające trójwymiarową strukturę sieciową zbudowaną z łańcuchów biopolimerów. Zwrócono także uwagę na sposoby wyznaczania podstawowych parametrów reologicznych (z użyciem reometrii rotacyjnej i oscylacyjnej) oraz mikrostrukturalnych, stosowanych do oceny tuszów spożywczych w zakresie ich drukowalności.
EN
The article characterizes the methods of producing of food inks that are used for 3D food printing. It was pointed out that currently, a limited amount of ingredients is used for the production of food inks, which must meet strictly defined rheological properties. At the same time, new components and food systems are constantly being tested as well as the technical parameters of 3D printers are being optimized. Macroscopically homogeneous gel and emulsion systems with high thixotropy, containing a three-dimensional network structure built of biopolimer chains, show particularly good suitability for printing. Attention was also paid to the methods of determining the basic rheological parameters (using rotational and oscillatory rheometry) and microstructural parameters applied to assess food inks in terms of their printability.
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Przedstawiono stan wiedzy i przegląd literatury w zakresie właściwości reologicznych polimerowych kompozytów drzewnych. Poddano dyskusji zagadnienie wyznaczania właściwości reologicznych kompozytów drzewnych na podstawie reometrii kapilarnej. Wskazano na rozległe możliwości reometrii kapilarnej w zakresie wyznaczania nie tylko krzywych płynięcia i krzywych lepkości, ale także badania zjawiska poślizgu, oceny granicy płynięcia, różnic naprężeń normalnych oraz lepkości podłużnej. Poddano dyskusji zagadnienie wpływu poprawek reometrycznych Rabinowitscha, Bagleya i Mooneya na położenie krzywej lepkości względem nieskorygowanej krzywej lepkości.
EN
A review, with 49 refs, of the state of knowledge on the problems of detg. the rheological properties of wood plastic composites based on capillary rheometry. The wide possibilities of capillary rheometry in the detn. of not only flow and viscosity curves, but also the study of the phenomenon of slippage, the evaluation of yield stress, normal stress differences and longitudinal viscosity were indicated. The problem of the effect of Rabinowitsch, Bagley and Mooney rheometric corrections on the position of the viscosity curve relative to the uncorrected viscosity curve was discussed.
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Przedstawiono stan wiedzy i przegląd literatury w zakresie właściwości reologicznych polimerowych kompozytów drzewnych. Poddano dyskusji zagadnienie wyznaczania właściwości reologicznych kompozytów drzewnych na podstawie reometrii kapilarnej. Wskazano na rozległe możliwości reometrii kapilarnej w zakresie wyznaczania nie tylko krzywych płynięcia i krzywych lepkości, ale także badania zjawiska poślizgu, oceny granicy płynięcia, różnic naprężeń normalnych oraz lepkości podłużnej. Poddano dyskusji zagadnienie wpływu poprawek reometrycznych Rabinowitscha, Bagleya i Mooneya na położenie krzywej lepkości względem nieskorygowanej krzywej lepkości.
EN
Rheological studies of polymer-wood composite (WPC) with polypropylene matrix contg. 50 or 70% by mass wood filler were performed. Flow and viscosity curves were detd. at 180, 190 and 200°C, and tests of longitudinal viscosity and yield stress at 190°C were carried out. The tested composites had typical pseudoplastic properties, but yield stress, slip phenomenon and stretching (longitudinal viscosity) were obsd. during the flow. The effect of Rabinowitsch, Bagley and Mooney rheometric corrections on the position of the viscosity curve in relation to the uncorrected viscosity curve was discussed.
This work focused on how self-compacting concrete (SCC) performs in situ in hot weather conditions at an ambient temperature of about 35°C. Tests for the rheological properties and compressive and splitting tensile strength aspects were carried out. The results of SCC mix ingredients on the rheological and hardened features of SCC mix were studied. Variations in the amount of portland cement content (CC), water to cement ratio (w/c), coarse to fine aggregate ratio (C : F), chemical admixture ratio, and pozzolanic admixture ratio were considered. Optimum values were obtained for these ingredients, which satisfied the SCC rheological characteristics and gave a 28-day compressive strength of 42 MPa, and 52 MPa after 28 days and 56 days, respectively. These optimum constituent values were 450 kg·m–3 of cement, 0.45 water cementitious ratio, and a coarse to fine material ratio of 1 : 0.8, a high range superplasticizer of 2%, and a mineral admixture of either 5% silica fume or 25% fly ash as a substitute for a similar amount cement.
The rheological properties of isotactic polypropylene (iPP) and its composites with unmodified and stearic acid-modified calcium carbonate (5, 10, 20, 30 wt%) were investigated. The processability factor K of the composites was determined based on changes in the mass flow rate (MFR). The assessment of rheological properties was carried out at high shear rates, in the injection process, using a special in-line measuring head. Measurements were performed at a temperature of 230°C, in the range of apparent shear rate from 19,100 to 101,900 s-1, based on the Ostwald-de Waele power-law model. Comparative analysis of the processing and rheological characteristics, as determined with two techniques (off-line measurements and in-line measurements), has shown a diverse behaviour of polymer composites in flows (flow resistances, the behaviour of the flow and viscosity curves, the power law index), resulting from a varying fill degree, applied filler type and measuring shear rate range.
PL
Zbadano właściwości reologiczne izotaktycznego polipropylenu (iPP) oraz jego kompozytów z niemodyfikowanym i modyfikowanym kwasem stearynowym węglanem wapnia (5, 10, 20, 30% mas.). Współczynnik przetwarzalności K kompozytów określano na podstawie zmian masowego wskaźnika szybkości płynięcia (MFR). Ocenę właściwości reologicznych przeprowadzono w warunkach dużych szybkości ścinania, w procesie wtryskiwania, przy zastosowaniu specjalnej głowicy pomiarowej typu in-line. Pomiary wykonano w temperaturze 230°C, w zakresie pozornej szybkości ścinania od 19 100 do 101 900 s-1, w oparciu o model potęgowy Ostwalda-de Waele’a. Analiza porównawcza charakterystyk przetwórczych i reologicznych, wyznaczonych dwoma technikami pomiarowymi (off-line i in-line), wykazała zróżnicowany sposób zachowania się kompozytów polimerowych w przepływach (opory przepływu, przebiegi krzywych płynięcia i lepkości, wykładnik płynięcia), wynikający z różnego stopnia napełnienia, rodzaju zastosowanego napełniacza oraz zakresu pomiarowego szybkości ścinania.
The latest research work in the field of electric power systems focuses on the development of new wire materials which will allow the increase of the transmission capacity of power lines currently in use. The reason for this research was the often limited possibilities of continuous and failure-free transmission of electricity. In this paper, the authors present research on a new aluminium-based alloy dedicated for use as a conductive braid in the HTLS cable group. There are many technical solutions for this group of cables on the market, although they are solutions with a number of disadvantages, ranging from their high price, various operational shortcomings, complicated installation techniques, and ending with the risk of monopolistic practices, which is related to the inability to attract several competitive suppliers. The main aim of the research was to develop a new alloy based on aluminium with the addition of silver and molybdenum dedicated for use in special overhead power cables. Experimental research on new materials focused on obtaining the necessary knowledge to produce an overhead wire from these alloys with higher current carrying capacity in relation to the currently used conventional wire materials based on aluminium.
Bread in Kosovo and beyond is still the most consumed food product, but the increase in consumer awareness of healthy foods has stimulated interest in the addition of various ingredients to improve its nutritional value and sensory properties. This study aimed to identify the ideal percentage of adding pumpkin flour through its influence on the rheological, nutritional, qualitative, and sensory properties of bread. Breads were produced with different amounts of pumpkin flour (control, 5%, 10%, 15%, and 25%). The results of the rheological properties with the Brabender farinograph and extensograph devices showed that the pumpkin flour pulp had an impact on the delay in dough formation, thus affecting the increase in water absorption, development time, stability, resistance, and energy of the dough. The falling number was very high for all types of bread over 350 seconds, and there were no significant differences between them (p < 0.05). The content of nutrients in the bread, such as fat, cellulose, and ash, increased along with the content of pumpkin flour, while the protein content decreased. Also, the content of iron, magnesium, potassium, and calcium increased along with pumpkin flour addition, while the content of zinc and manganese decreased. The bread with 5% pumpkin flour had the best specific volume, while the control bread and the bread with 5% pumpkin flour had better acidity. The bread with 5% pumpkin flour and control bread had better sensory properties, but even the breads with 10% pumpkin flour had good sensory properties. Therefore, using less than 10% pumpkin flour is suggested in the production of bread without compromising the quality or sensory properties of the bread.
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Zastosowanie glin kalcynowanych, łączonych w trójskładnikowe mieszanki z wypełniaczem wapiennym i cementem cieszy się w ostatnich latach dużym zainteresowaniem. W artykule omówiono wyniki badań reologicznych i wytrzymałości na ściskanie trzech rodzajów glin kalcynowanych w połączeniu z proszkiem marmurowym i cementem, stosowanych jako trójskładnikowe spoiwo w zaprawach samozagęszczalnych. W celu ustalenia różnych kombinacji spoiw zastosowano metodę projektowania mieszanki siatkowo-sympleksową, z pięcioma poziomami. Odpowiedzi układu oceniano pod względem właściwości reologicznych i wytrzymałości na ściskanie. Badania przeprowadzone na trójskładnikowych mieszankach zapraw samozagęszczalnych to średnica rozpływu mieszanki, czas wypłynięcia mieszanki z V-lejka, wartość plastyczności, lepkość oraz wytrzymałość na ściskanie po 28, 90 i 365 dniach. Stwierdzono, że zastąpienie cementu przez kalcynowane gliny oraz pył marmurowy w mieszankach trójskładnikowych spowodowało zmniejszenie zdolności płynięcia poprzez zmniejszenie rozpływu mieszanki i wydłużenie czasu wypłynięcia mieszanki z V-lejka. Jednak łączne działanie pyłu marmurowego oraz prażonych glin jest bardziej odpowiednie do wytworzenia płynnych mieszanek zapraw przy zachowaniu odpowiedniej lepkości. W zakresie wytrzymałości na ściskanie stwierdzono progresywnie rosnący trend dla 28-dniowej wytrzymałości na ściskanie wraz ze zwiększeniem udziału pyłu marmurowego oraz prażonych glin.
EN
The use of calcined clays [CC], combined in ternary blended with the limestone filler and cement has received considerable attention in recent years. This paper discusses the results on the rheological and compressive strength of three types of calcined clays in combination with marble powder and cement, used as ternary binder in self-compacting mortars. A simplex-lattice mixture design approach was used, with five levels, to establish the different binder combinations. The responses of the system were evaluated in terms of rheological properties and compressive strength. The tests conducted on SCM ternary mixes are slump flow diameter, v-funnel flow time, yield value, viscosity and compressive strength at 28, 90 and 365 days. It was concluded that the replacement of cement with calcined clays and marble powder in ternary mixes reduced the flowability by decreasing slump flow and increasing v-funnel time. However, the combined effect of marble powder and calcined clays is more appropriate to produce flowable SCM mixes while maintaining an adequate viscosity. In terms of compressive strength. A progressively increasing trend was observed for 28 days compressive strength with the increase in marble powder and calcined clays in binary proportions.
The effects of hydroxypropyl methylcellulose (HPMC) on the rheology and viscoelasticity of cement-limestone paste were evaluated, as was the mechanism of HPMC from the viewpoint of zeta potential and adsorption amount. The results revealed that the greater the content of HPMC or the viscosity of its aqueous solution, the lower the fluidity of the composite paste and therefore the higher the rheological parameters. The relation between torque and rotational velocity of cement-limestone paste is linear; nevertheless, the shear thickening degree of paste increased following the addition of HPMC, demonstrating typical viscoelastic properties. The addition of HPMC prolonged the induction duration and delayed the emergence of the exothermic peak of hydration, decreased zeta potential and conductivity, and increased the propensity of suspension particles to agglomerate. The adsorption amount of polycarboxylate superplasticizer (PCE) decreased with increasing aqueous solution viscosity and HPMC concentration due to the winding effect of HPMC’s high molecular chain structure and the competing adsorption of HPMC and PCE.
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3D printing technology has attracted great attention from the construction industry for its superior performance compared with traditional construction technology. In this study, the rheological properties of fresh mixed pastes with different contents of fly ash (FA) and granular ground blast furnace slag (GGBFS) were evaluated by analyzing rheology indices and the fitting of the Bingham model, and the relationship between the rheological properties, the buildability of 3D Printing Material (3DPM) and n value of the Rosin-Rammler distribution function was established. The results show that with increasing FA or GGBFS content, the rheological properties (fluidity, yield stress, and plastic viscosity) of fresh mixed pastes first improved and then deteriorated, and the n value (constant for the width of the particle distribution) first decreased and then increased. When the FA content was 20%, the paste fluidity reached a maximum value of 178 mm, the n value (1.01782) was the smallest, the particle size distribution was the widest, the accumulation was the best, and the buildability of 3DPM was the best. In addition, it can be seen from the SEM analysis that FA and GGBFS participate in the cement hydration to a limited extent, which mainly play the role of compaction and adjustment of particle size distribution. This is consistent with the test results of XRD. In short, by adjusting the amount of FA and GGBFS, the particle size distribution of the whole cementitious material system changes. When the fluidity of 3DPM was between 160 and 180 mm, the smaller the n value of the Rosin-Rammler distribution function, the better its buildability was.
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