Addition Of Nanosilica Research Articles

Nanotechnology-Enabled Innovations in Cement: Enhancing Durability, and Impact Load Resistance with Nanocellulose, Nano Silica, and Nano Clay Additives

Nanotechnology-Enabled Innovations in Cement: Enhancing Durability, and Impact Load Resistance with Nanocellulose, Nano Silica, and Nano Clay Additives

Optimized enhanced energy absorption in polymer nanocomposites reinforced with nano-clay, nano-silica, and diethylenetriamine

In today’s world, where various industries face ever-increasing developments, improving people’s lives and preserving their property and lives are important issues in industrial production. One of the most unpleasant events in life is a collision while using the vehicle. Therefore, in recent decades, the high importance of this issue has attracted the attention of many researchers. The present study investigates the energy absorption of polymer nanocomposites with cylindrical and conical structures with different percentages of clay and silica nanoparticles to determine the various effects of nanomaterials and the effect of structure geometry on energy absorption under quasi-static tests. This experiment has been designed with the help of Design Expert software and the Box-Benken method. Also, nanomaterials between changes of 0-0.4% and diethylenetriamine material with weight% 1,3,5 have been used. From the results, it can be depicted that with the increase of the nanomaterial in this range, energy absorbed by the addition of nano silica up to the central point, i.e., 0.2%, an increase has been witnessed and after that, its intensity has decreased. Within this range, there is an observed significant rise of up to 0.4% for the nano clay material, while its trend keeps up with the previous intensity after the central point. However, in diethylenetriamine material, the highest energy absorption at the central point was 0.2%, after which a downward trend was observed. Also, in the investigation of the geometry of the structure, it was found that cone-shaped structures have higher energy absorption.

Damping and acoustic properties of nanosilica filled poly(styrene-acrylate) interpenetrating polymer networks (IPNs): Effect of nanocomposite preparation method

Research on noise pollution reduction has focused on utilizing damping coatings and polymer nanocomposites to enhance sound absorption. Nanosilica/poly(styrene-acrylate) nanocomposites as a water-based coating were prepared through in-situ emulsion polymerization and direct mixing methods at varying concentrations of 1, 2, and 3 wt% of nanosilica. Fourier transform infrared (FTIR) spectroscopy revealed that the inclusion of surfactant-containing micelles and a more extended synthesis period in the in-situ synthesis technique enhanced the interaction between silica nanoparticles and polymer chains. Dynamic light scattering (DLS) analysis showed a unimodal distribution and an acceptable range of polydispersity index (PDI) for neat and nanocomposite latexes. The addition of silica nanoparticles enhanced the stability of latex particles, especially evident in the direct mixing method. The field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) images confirmed the better dispersion of nanoparticles within the polymer matrix in the in-situ method. The addition of nanosilica resulted in a significant increase in pseudoplastic behavior and viscosity, notably in the in-situ synthesis. In both the in-situ synthesis and direct mixing techniques, the addition of 1 wt% of nanosilica resulted in an increase in the damping factor of nanocomposite films to about 2. However, when the nanosilica content was further increased to 3 wt%, the damping factor decreased. Acoustic tests demonstrated improved sound absorption with silica nanoparticles, yielding noise reduction coefficient (NRC) values of 0.49 and 0.46 for in-situ synthesis and direct mixing. The direct mixing method notably enhanced tensile properties at all nanoparticle content levels. Dried nanocomposite films exhibited superior UV-blocking capabilities compared to neat polymer films.

Hybrid Effect of Metakaolin and Nano-Silica on Mechanical and Durability Parameters of Mortar

The incorporation of pozzolanic materials such as nano silica and metakaolin in cementitious materials has gained significant attention in recent years due to their potential to improve the mechanical and durability properties of cement-based composites. This thesis investigates the hybrid effect of nano silica and metakaolin on the mechanical and durability properties of cement mortar. The research work involved the preparation of cement mortar specimens with varying proportions of nano silica and metakaolin, which were then subjected to a series of mechanical and durability tests. The mechanical tests included compressive strength, while the durability tests included water absorption and elevated temperature test. The study showed that the addition of both nano silica and metakaolin to cement mortar resulted in a significant improvement in the mechanical properties of the mortar. Additionally, the hybrid effect of nano silica and metakaolin resulted in enhanced durability of the cement mortar, with a significant reduction in water absorption and improved temperature resistance. The findings of this study will have significant implications for the development of sustainable and durable cementitious materials. The use of pozzolanic materials such as nano silica and metakaolin can reduce the consumption of cement and the associated carbon footprint while also improving the durability and long-term performance of cement-based composites. Overall, this study suggests that the incorporation of nano silica and metakaolin can lead to significant improvements in the mechanical and durability properties of cement mortar, making it a promising material for use in various construction applications.

An investigation of the mechanical strength, environmental impact and economic analysis of nano alkali-activated composite

The current study explores both the mechanical strength and life cycle assessments of fly ash (FA)-based alkali-activated concrete (AAC) with/without colloidal nano-silica (NS) addition at high and low molar concentrations of sodium hydroxide in the activator fluid (12 M and 3 M). The cradle-to-gate approach is used to establish the system boundaries for life cycle assessments (LCA). The environmental impact of AAC (with/without NS) and conventional cement concrete (CC) mixtures was determined using the ReCiPe midpoint and endpoint approaches across various impact categories. The AAC mixes with and without NS addition reduce greenhouse gas (GHG) emissions by 30 % and 25 % with respect to CC mix, respectively. Within the majority of impact categories, sodium silicate and sodium hydroxide production are the primary contributors, accounting for up to 91 %. However, in water depletion, global warming potential, and fuel depletion, the overall contribution is as high as 65 %. Also, the AAC mix with and without NS addition consumes 34 % and 14 % less electricity during its production with respect to the CC mixture. The CC mixes have almost 70 % more ecological damage and approximately 30 % more health risk than AAC with and without NS. However, the NS-modified AAC shows 20 % lower ecological and health risks than AAC without NS. The effect of resource scarcity on NS modified AAC is 50 % less than that of other mixes, including both AAC mix without NS and CC mix. In comparison to AAC without NS, the NS modified AAC demonstrates an 18 % reduced impact on resource scarcity. Finally, cost analysis demonstrates that AAC with NS is 16 % less expensive than CC, while AAC without NS is 26 % cheaper than CC. AAC containing 6 % NS inclusions exhibits environmental and economic benefits in addition to its enhanced mechanical performance, indicating its potential for widespread practical usage.

Tensile strength and failure mechanism of rock–cement sample: Roles of curing temperature, nano-silica and rock type

Understanding the tensile strength and failure mechanism of rock–cement interfacial transition zone (ITZ) is of vital significance to the sealing integrity of cement sheath under downhole condition. Taking advantage of multiple techniques, i.e., digital image correlation (DIC), nano-indentation, XRD-Rietveld analysis, 29Si MAS solid NMR, and SEM-EDX, this study is devoted to investigating the impacts of curing temperature, rock type, and the addition of nano-silica (NS), on the tensile strength and failure mechanism of rock–cement sample. The experimental results show that both the curing temperature and the addition of NS leads to the formation of more C-S-H, which densifies the ITZ microstructure and responsible for high tensile strength of rock–cement samples; the tensile strengths of shale-cement samples are consistently higher than those of sandstone-cement sample; the crack velocities for rock–cement samples under three-point bending tests are approximately 1 mm/s, the crack velocities for rock–cement samples are slowed down when the NS is incorporated in cement paste, but they are independent on the rock type and curing temperature.

Synergizing empirical and AI methods to examine nano-silica's microscale contribution to epoxy coating corrosion resistance

Epoxy-nanomaterials offer a promising solution to combat corrosion threatening civil infrastructure. To examine the impact of nano silica on corrosion resistance, varying amounts of nano silica, ranging from 0.0 to 3 wt%, were introduced into the epoxy matrix. Mechanical properties were studied through studying the dog-bone tensile strength and tribological aspects were assessed through mass loss abrasion tests. Corrosion resistance performance was studied using electrochemical impedance spectroscopy (EIS) and salt spray tests. Nano structure of the coated specimens was studied after salt spray tests using SEM-EDX analysis. Micro Chromatography (M-Ct) technique was employed to investigate the pore formation in the epoxy matrix. Besides, atomic force microscopy (AFM) was introduced to study surface roughness. The test results displayed a notable improvement (5–10 %) in tensile strength upon the introduction of nano silica. Taber tester results showed a reduction in mass loss with the addition of nano silica. Electrochemical impedance spectroscopy (EIS) studies further established a significant increase in corrosion resistance, having an impedance of 12 GOhm.cm2 for epoxy matrix samples containing 2.5 % nano silica after a 768-h salt spray test. SEM-EDX analysis revealed the absence of iron content in the epoxy matrix reinforced with uniformly distributed nano silica. Surface roughness assessments illustrated that nanolaminates contributed to an increase in overall roughness, minimizing surface irregularities in the epoxy matrix. Micro-CT scanning results proposed a decrease in epoxy matrix porosity upon the addition of nano silica. AI based prediction model helped to understand the relationship between surface roughness and corrosion. In summary, the experimental findings suggest valuable insights for future advancements in the development of protective coatings for worldwide civil infrastructures.

Effect of kaolin-nano-silica mixture on geomechanical properties enhancement of soils

Weak soil is a major obstacle facing the urban development of any site with other exceptional merits. The current study aims to investigate the utilization of nano-silica in enhancing the mechanical properties of weak kaolin soils. Design mixes using different percentages of nano-silica were investigated in the range between 0.25–1.20% from the dry weight of the kaolin soil. Various chemical, physical, and mechanical properties of each mixture have been investigated. The obtained results indicated that nano-silica addition to such kaolin soils decreased the plasticity index and the maximum dry density while increasing the plastic limit, the Liquid limit, and the optimum moisture content. In different curing days of the tested mixtures, maximum dry density was decreased, while the optimum moisture content increased. The optimum value of added nano-silica was less than 1% of the soil dry weight. In the modified kaolin soil with 0.9% nano-silica, the plastic limit was increased by 29%, while the liquid limit decreased by 13% in comparison with the untreated sample. After 28 days of the cured sample, the unconfined compressive strength readings increased by almost 14% compared to its reading on day one. Also, the California bearing ratio results recorded significant enhancement with nano-silica additives in comparison with the untreated kaolin soil. After 28 curing days, the sonicated samples recorded enhancement in the unconfined compressive strength readings by more than 5% and 9% with the additive N-Si (0.3% and 0.9%), respectively, when compared with the unsonicated samples.Graphical

Effect of ball milling conditions on the microstructure for alumina-based ceramic with nano-silica additives

Abstract Alumina-based ceramics, known for their excellent high-temperature stability and tensile strength, are utilized across various sectors like metallurgy, aerospace, and chemicals as thermal insulators and reinforcements. The mechanochemical method, which involves mechanical actions like stirring and grinding to induce chemical reactions without solvents, offers a green, time-efficient approach with minimal pollution. This technique is pivotal for nanomaterials preparation. This study successfully crafts nano-silica-enhanced alumina-based ceramics via mechanochemical methods. The impact of mechanochemical processes on ceramic properties is assessed through particle size, N2 adsorption, and various microscopic analyses.

Improving Environmental Stress Cracking Resistance of High-Density Polyethylene Grades by Comonomer Addition and Nanocomposite Approach.

The aim of this paper is to determine the effect of polymer density, correlated to the comonomer content, and nanosilica addition on the mechanical and Environmental Stress Cracking Resistance (ESCR) characteristics of high-density polyethylene (HDPE). In this regard, five HDPE samples with similar Melt Flow Index (MFI) and molar mass but various densities were acquired from a petrochemical plant. Two polymerization reactors work in series and differ only in the amount of 1-buene comonomer fed to the second reactor. To ascertain the microstructure of the studied samples, GPC and SSA (successive self-nucleation and annealing) analyses were accomplished. All samples resulted having similar characteristics but slightly various SCB/1000 C=7.26-9.74 (SCB=Short Chain Branching). Consequently, meanwhile studied HDPEs reveal similar notched impact and stress at yield values, the tensile modulus, stress-at-break, and elongation-at-break tend to demonstrate different results with the SCB content. More significantly, ESCR characteristic varied considerably with SCB/1000 C extent, so that higher amount of SCB acknowledged advanced ESCR. Notably, blending HDPE sample containing higher amount of SCB/1000 C, with 3 wt.% of chemically modified nanosilica enhanced ESCR characteristic by 40 %. DFT (Density Functional Theory) calculations unveiled the role of the comonomer, quantitatively by binding energies and qualitatively by Non Covalent Interaction (NCI) plots.

Nano-silica electrolyte additive enables dendrite suppression in an anode-free sodium metal battery

Sodium (Na)-based batteries are being explored as a sustainable and cost-effective alternative to Lithium (Li)-ion batteries. In particular, an “anode-free” Na metal battery offers the possibility to match or even exceed the energy density of the incumbent Li-ion technology. Nevertheless, the present lifespan of these batteries is insufficient to render them suitable as an energy source for current electronic devices and grid systems. The main reason for this is the evolution and growth of Na metal dendrites during the charge-discharge process. In this study, we report a “nano-silica modified suspension electrolyte” that improves the average coulombic efficiency and cycling performance of anode-free Na metal batteries. The nano-silica additives increase the Na+ diffusion coefficient in the electrolyte by ∼1000-fold, thereby decreasing the nucleation overpotential and inhibiting the formation of Na metal dendrites. We demonstrate that a Na|Cu half-cell with the suspension electrolyte can cycle stably for over 500 cycles at ∼1 mA cm−2 current density and an aerial capacity of ∼2 mAh cm−2. When paired with an Na3V2(PO4)3 (NVP) cathode, the anode-free NVP|Cu full-cell device with the nano-silica infused electrolyte drastically outperformed the conventional electrolyte in terms of specific capacity retention and coulombic efficiency.

Durability performance of superabsorbent polymer incorporated concrete modified by nano-silica addition in seasonal frozen regions

In seasonal frozen regions, ion erosion and freeze-thaw (F-T) cycles threaten pavement concrete durability. This study evaluates the suitability of superabsorbent polymer (SAP) concrete modified by nano silica (NS) for enhancing durability. Tests were conducted to analyze chloride impermeability and frost resistance effects on modified SAP concrete. The coupling impact of ion erosion and freeze-thawing was also evaluated. Mercury intrusion porosimetry (MIP), scanning electron microscopy, and energy dispersive spectrometry were employed to investigate microstructure characteristics. Results demonstrated that NS-modified SAP concrete exhibited high resistance to ion erosion and F-T cycles. Adding 3 % NS reduced the relative dynamic elastic modulus (RDEM) loss by 23.21 % after 300 F-T cycles. The enhancement was more pronounced under the coupled action of ion erosion and freeze-thawing, and the RDEM loss and scaling quantity per unit area of NS-3 % decreased by 13.21 % and 41.48 % respectively, and compressive strength was 28.33 % higher than that of SAP concrete after 135 salt-frost cycles. MIP testing indicated that 3 % NS significantly improved pore structure, reducing deterioration in much harmful pores by 12.82 %. SAP promoted the efficient pozzolanic reaction of NS, generating high-density C-S-H. Additionally, second-hydration products were adsorbed by the ionization of SAP microgel, densifying its shrinkage voids and delaying ITZ width and micro-crack propagation, thereby enhancing concrete durability.

Comparative fracture surface analysis of adhesively bonded dissimilar lap joints: Nanosilica effect

AbstractThis research presents a comparative analysis of the fracture surfaces of adhesively bonded dissimilar single lap joints (DSLJs) and investigates the effect of nanosilica (NS) additives on their fracture behavior and performance. The study focuses on DSLJs composed of aluminum (Al), stainless steel (SS), copper (Cu), and carbon fiber reinforced polymer (CFRP) adherends bonded with an epoxy adhesive. The fracture surface of DSLJs is further analyzed by introducing two parameters: fractional total fracture area (aT) and the surface sensitivity of each adherend (aSurface). These parameters serve as benchmarks to predict the final load capacity of the adhesive joints. It is found that a decrease in and an increase in the sensitivity of the adherend with a lower Young's modulus lead to higher load capacity. Tensile tests revealed that incorporating NS up to a critical weight percentage of 0.6 wt% improves the proposed surface parameters and significantly contributes to higher levels of load capacity and absorbing greater amounts of energy to failure. Furthermore, numerical simulations offer insights into stress distribution and the mechanism of plastic deformation propagation, providing additional support for the experimental findings.Highlights NS up to 0.6 wt% enhances the mechanical properties of DSLJs. NS–epoxy interactions characterized through Fourier transform infrared and transmission electron microscopy analysis. Fracture surface patterns help to predict the final load capacity of DSLJs. Plastic propagation in epoxy verifies fracture surface pattern in DSLJs.

Effect of nanosilica on the hydrological properties of loess and the microscopic mechanism

Loess areas, such as the Loess Plateau, are characterized by a fragile ecological environment, high soil erosion, and frequent geological disasters due to the unique hydrological properties of loess (e.g., collapsibility and permeability). Therefore, the loess must be stabilized for use in engineering construction. Traditional stabilizers (lime, cement, and fly ash) cause environmental problems, such as soil salinization and greenhouse gas emissions. Therefore, this study investigated the effect of nanosilica on the hydrological properties of loess and the microscopic mechanism. Different nanosilica contents (0.2%, 0.4%, 0.8%, 1%, and 3%) were added to loess sample, and the particle size distribution, Atterberg limits, collapsibility, and soil water characteristics were analyzed. The results revealed the following. The addition of nanosilica changed the particle size distribution, liquid limit, plastic limit, and plasticity index of loess. After the addition of nanosilica with different contents, the loess collapsibility coefficient curve shifted downward, the soil water retention curve shifted upward, and the unsaturated permeability coefficient curve shifted downward. The pores between particles were filled, and the number of large and medium pores and the pore connectivity were lower after the nanosilica addition. The surface of the coarse particles adsorbed more fine particles, and a large number of micro-aggregates or clay aggregates were present in the pores between particles. In conclusion, the environmentally friendly material nanosilica can be used to improve the hydrological properties of loess, which is applicable to alleviating soil erosion and preventing geological disasters on the Loess Plateau.

Impact of nano-silica on the mechanical properties of lightweight concrete

Abstract Recent research has shown that lightweight concrete (LWC) offers a series of advantages, leading to a noteworthy evolution in this field. Numerous high-performance features are offered by nanomaterials added to LWC. This study examines the impact of nano-silica (NS) at concentrations of 1 %, 3 %, 5 %, 10 %, 15 %, and 20 % on the properties of LWC both fresh and hardened. Slump tests were used to estimate the workability of all mixes. To assess for toughened qualities, tests for density, compressive strength, and microstructure were employed. In comparison to the reference mixture, the application of NS improved the microstructure and total compressive strength. The percentage of NS at 5 % with a 90-day increase the compressive strength by 77 %. The microstructure analyses demonstrate that the hydration process of the cement paste can be changed with the addition of nano-silica, and new types of hydration products have been observed in nano-modified cementitious matrix. The interface between the lightweight aggregates and the cement paste can be reinforced by nano-silica due to the new types of hydration products.

Preparation of Modified α-Cyanoacrylate

Abstract In order to increase the viscosity and tensile shear strength of ethyl α-cyanoacrylate, Nano-silica modified α-cyanoacrylate (NS/α-Cyanoacrylate), hydroxylated multi-walled carbon nanotubes modified α-cyanoacrylate (CNTs/α-Cyanoacrylate) and epoxy resin modified α-cyanoacrylate (EP/α-Cyanoacrylate) were synthesized using the improved Knoevenagal Condensation method. The structural characteristics of the prepared ethyl α-cyanoacrylate were characterized using Fourier transform infrared spectroscopy. For the modified ethyl α-cyanoacrylate, the relationships between the filler content and the viscosity or tensile shear strength were analysed by rotary viscometer and electronic universal testing machine. Finally, it was found that the addition of Nano-silica, hydroxylated multi-walled carbon nanotubes and epoxy resins can improve the viscosity and tensile shear strength of α-cyanoacrylate. The best dosages of Nano-silica, hydroxylated multi-walled carbon nanotubes and epoxy resin were 5%, 0.2% and 4.5 %.

Influence of stacking sequence and nano-silica fortification on the physical properties of veli karuvelam – peepal hybrid natural composites

Abstract A hybrid composite incorporating veli karuvelam and peepal fibers was fabricated, with the addition of nanosilica as a filler to enhance composite performance. The impact of nanosilica and layering sequence on the physical properties of the composites was investigated. Initially, two types of hybrid composites i.e. peepal/veli karuvelam/peepal (PVP) and veli karuvelam/peepal/veli karuvelam (VPV) were developed by means of hand layup method, varying the layering sequence of veli karuvelam and peepal fibers. The PVP composite was identified as the most promising based on tensile strength (71 MPa), attributed to the optimal packing of high-strength peepal fibers. Subsequently, nanosilica was incorporated into the PVP composite at different weight percentages (1, 2 and 3), and its influence on composite performance was analyzed. The PVP composite containing 2 wt% SiO2 showed impressive mechanical properties, with a tensile strength of 76 MPa, a flexural strength of 104 MPa, an impact strength of 4.5 kJ/m2, and a hardness of 89 on the Shore D scale. The findings indicate that a PVP composite containing 2 wt% SiO2 has potential for use in engineering applications.

Extraction and characterization of nano-silica particles to enhance mechanical properties of general-purpose unsaturated polyester resin

Abstract Unsaturated polyester resin (UPR) is the most versatile liquid polymer with a wide range of applications in every aspect of the industry but it has low impact strength, low elongation at break, and low toughness. Its mechanical properties can be enhanced with the addition of an optimum percentage of nano-silica fillers by using ASTM polymer test standards, which have been followed by various research groups. For this research, enhanced mechanical properties of the resin have been tested for 0.5, 1, 2, 3, and 4% amount by weight fraction of the nano-silica as fiber nanomaterial. The sugar cane bagasse ash was collected from the Wenji Sugar Factory and extracted with the required size of the particle, which is 10 nm. The ability of extraction is used to manipulate the particle size as the researcher needs. The aim is to determine the enhanced mechanical properties of the UPR by the addition of optimum nano-silica particles. Nanoparticles have the effect of filling porous regions, crack path deflection, and crack bridging capability of the material, which provides good adhesion with the matrix to increase the mechanical properties of composite materials. Experimental result dictates that 0.5% nano-silica addition with 10 nm particle size performs best by enhancing the mechanical properties of composite material up to 30.45% for tensile, 33% for compression, 17.8% for flexural, a slightly 10% improvement for impact test and it shows an overall 27% better performance than the pure UPR. Thermal stability and glass transition temperature were not influenced by the addition of nano-silica.

Investigation of Microstructural Properties of Nano-modified Concrete for Sustainable Environment

The creation and evaluation of Nano-modified concrete, with an emphasis on its microstructural characteristics, is the main goal of this extensive study. The inclusion of nanosilica and nanoclay not only enhances the characteristics of concrete but also contributes to mitigating soil pollution. By adding nanosilica and nanoclay as additional cementitious materials, the study intends to assess the structural integrity of nano-modified concrete using cutting-edge techniques like Scanning electron microscopy, Transition electron microscopy and X-ray diffraction. Four different concrete compositions with variable amounts of nanosilica and nanoclay additions (0%, 5%, 10% and 15% of nano additives by weight of fine aggregate) and a 3% cement replacement rate were cast and evaluated throughout the experimental phase. A comparison with regular concrete revealed significant improvements in microstructures, demonstrating the efficacy of nano-modified concrete without sacrificing necessary characteristics. Slump values increased with the addition of nano-silica and nanoclay, indicating better workability and smoother concrete surfaces. The study's findings indicate that the development of Nano-modified concrete has great potential as an advanced building material. In addition to providing instant structural gains, the use of nanosilica and nanoclay enhances the long-term performance of concrete buildings and creates new opportunities for creative and long-lasting building techniques.

On the Flow of a Cement Suspension: The Effects of Nano-Silica and Fly Ash Particles.

Additives such as nano-silica and fly ash are widely used in cement and concrete materials to improve the rheology of fresh cement and concrete and the performance of hardened materials and increase the sustainability of the cement and concrete industry by reducing the usage of Portland cement. Therefore, it is important to study the effect of these additives on the rheological behavior of fresh cement. In this paper, we study the pulsating Poiseuille flow of fresh cement in a horizontal pipe by considering two different additives and when they are combined (nano-silica, fly ash, combined nano-silica, and fly ash). To model the fresh cement suspension, we used a modified form of the power-law model to demonstrate the dependency of the cement viscosity on the shear rate and volume fraction of cement and the additive particles. The convection-diffusion equation was used to solve for the volume fraction. After solving the equations in the dimensionless forms, we conducted a parametric study to analyze the effects of nano-silica, fly ash, and combined nano-silica and fly ash additives on the velocity and volume fraction profiles of the cement suspension. According to the parametric study presented here, larger nano-silica content results in lower centerline velocity of the cement suspension and larger non-uniformity of the volume fraction. Compared to nano-silica, fly ash exhibits an opposite effect on the velocity. Larger fly ash content results in higher centerline velocity, while the effect of the fly ash on the volume fraction is not obvious. For cement suspension containing combined nano-silica and fly ash additives, nano-silica plays a dominant role in the flow behavior of the suspension. The findings of the study can help the design and operation of the pulsating flow of fresh cement mortars and concrete in the 3D printing industry.