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Articles • Matéria (Rio J.) 31 • 2026 • https://doi.org/10.1590/1517-7076-RMAT-2026-0097 linkcopy

Open-access Performance evaluation of nano-silica and calcined nano-clay modified cement mortar

AuthorshipSCIMAGO INSTITUTIONS RANKINGS

ABSTRACT

The necessity for sustainable construction materials is driving research into alternatives to typical Portland cement, which has a significant environmental impact. This study examines the effect of Nano-Silica (NS) and Calcined Nano-Clay (CNC) on the fresh, mechanical, durability, and microstructural properties of cement mortar. Cement was partially replaced with varying proportions of NS and CNC, and a chemical admixture was used to achieve workable mixes. The behaviour of fresh mortar, strength development at different curing ages, resistance to aggressive environments, and internal microstructure were systematically evaluated. The compressive and flexural strength of NM7 mix (4% NS + 6% CNC) were found to be the highest and the mechanical performances were improved significantly in nano-modified mortars. Compared with the conventional mortar, the durability evaluation showed that the weight loss and strength degradation of the mortar were less under the action of acid and sulphate, and the water absorption was less. The overall results show that the combined effect of NS and CNC effectively improves the strength and durability of cement mortar.

Keywords:
Nano-silica; Calcined nano-clay; Cement mortar; Mechanical properties; Microstructure

1. INTRODUCTION

Cement mortar is a fundamental construction material, and is extensively employed in masonry, plastering, surface finishing as well as repairing purposes. Its performance has a direct influence on the strength, the durability and the long run serviceability of buildings and infrastructure [1, 2]. Regardless of its widely-used nature, traditional cement mortar frequently has the disadvantage of an increased porosity, reduced ability to resist ingress of moisture, premature cracking in a early age, and deterioration with excessive exposure to the aggressive environment [3]. Portland cement serves as the primary binding material in mortar; however, its production raises serious environmental concerns [4, 5] The manufacture of cement involves energy-intensive clinker production and the calcination of limestone, both of which contribute significantly to global CO2 emissions [6, 7, 8, 9, 10] With increasing urbanization and growing construction demands, there is a strong need to reduce the environmental impact of cement mortar [11]. This has led to increased interest in incorporating sustainable and performance-enhancing alternatives into mortar systems, with the aim of lowering carbon emissions while maintaining or improving strength and durability characteristics [12, 13].

The utilization of nanoparticles in cement-based systems has garnered significant attention in recent years as a result of their capacity to alter material behavior at the micro- and nanoscale [14, 15].

Nanomaterials, including nano-silica, nano-clays, and other fine mineral additives have been shown to improve particle packing, refine pore structure, and enhance the development of hydration products [16, 17, 18, 19]. These materials when used in concrete and mortar may have an effect on fresh and hardened properties, resulting in better strength, the decrease in permeability, and increased durability [20, 21]. They comprise very fine particles that make them fill in micro-voids in the cement matrix and have a denser and more uniform internal structure [22, 23].

In mortar applications, nanoparticles are especially effective due to the higher paste content and its absence of coarse aggregates [24]. The nanomaterials and cement particle interaction can enhance the speed of the hydration reactions and enhance bonding of the binder and fine aggregate. Consequently, there was a tendency that mortar systems modified using nanomaterials tend to have better mechanical performance and resistance to environmental degradation [25]. These strengths show the increasing potential of nanotechnology as a viable and efficient strategy in the creation of high-performance and long-lasting cement mortar to meet the current construction demands.

Calcined Nano Clay (CNC) is a very attractive SCM, which is formed by heating the natural clay to specific temperature, thus, releasing its pozzolanic properties [26, 27, 28, 29]. The dispensation of natural clays by thermal treatment improves the pozzolanic properties of them, thus forming CNC [30, 31]. Heat disrupts the stratification of the clay minerals, the effect of which is increased reactivity. Nano clay is calcined to react with calcium hydroxide that is formed during the hydration of cement, forming more C-S-H and enhancing the strength of the material [32]. This process improves densification and ultimate strength of the cement skeleton. The smaller particle size of the CNC enhances the filler effect, hence diminishing the overall porosity and enhancing concrete durability [33].

Nano-silica (NS) is a very reactive form of silicon dioxide, which has a particle size of nanometre size [34, 35]. The larger surface area and smaller size of nano-silica particles speed up the hydration reaction in concrete, resulting in a more refined and compact microstructure. The improvement of more C-S-H gel formation makes the compressive strength better in both the short and long term [36, 37, 38]. However, incorporation of NS is not without problems particularly in matters of workability. Earlier studies have revealed that the inclusion of NS in concrete reduces workability due to its high surface area. NS has a high surface area and agglomeration potential, which could adversely affect the workability and uniformity of concrete mix, and therefore, result in a higher water requirement in the concrete mix [39]. The increase in water demand correlates with the proportion of NS in concrete, attributable to the fineness and elevated specific surface area of NS particles, the prompt contact of NS with the liquid phase of the cementitious mixture, and the substantial water absorption capacity of NS [40, 41].

NS with smaller particle size showed higher early-age strength compared to larger-sized NS [42]. NAJI GIVI et al. [43] also discovered nano-silica in the form of 15 nm average particles created stronger concrete at early ages than those with 80 nm but beyond 90 days the concrete with 80 nm particles was stronger. In the nano-engineered FA concrete, SINGH et al. [44] discovered that the NS particle created a higher strength at an early age. The chloride ion resistance to penetration in NS concrete was much higher when compared to reference concrete mixes [45].

This study examines the influence of incorporating CNC and NS as partial substitutes for cement in concrete mortar at varied proportions. The purpose of this research study is to assess the impact of these parameters on the workability, strength development, and microstructural properties of cement mortar. This research aims to provide insights into the creation of more sustainable concrete mixtures that minimize cement usage while preserving or enhancing performance through the identification of suitable replacement levels.

1.1. Research significance

This research is significant as it examines the enhancement of strength and durability of cement mortar with the use of NS and CNC. NS increases the strength of cement mortar in the sense that it speeds up the process of hydration and it also fills small holes and eventually increases the overall strength. CNC is also a filler which reduces the porosity of the mortar which increases its ability to resist water, chemicals and harsh weather conditions. The utilization of these nanoparticles extends the lifespan of the mortar, thereby rendering the structure more durable and inexpensive to preserve. Most previous studies have been conducted on the individual use of NS, or CNC, in cement-based materials. Very limited work has been done on their combined use in cement mortar. Thus, this study provides solutions to this gap by assessing the combined effect of NS and CNC and finding an optimum mix for better performance.

2. MATERIALS

The present study utilized Grade 53 of ordinary Portland cement, as defined in IS 8112-2013 [46]. The cement used in this experiment had a specific gravity of 3.15, a normal consistency of 31.0%, and a minimum fineness of 307 kg/m3. Its initial and final setting time was recorded at 57 minutes and 218 minutes respectively. The fine aggregate (FA) employed in the experiment was gathered in the Cauvery River basin in Erode, India, and it complies with the requirements of IS 383:1970 [47]. The fineness of the material is 2590 kg/m3 and its’ specific gravity is 2.64.

The Nano silica (NS) and Calcined Nano Clay (CNC) of this research were purchased in Astraa Chemicals in Chennai, India. NS contains high activity of pozzolans and fineness grain and is significantly important in enhancement of mechanical strength and durability of the mortar, enhancing the microstructure and closing the voids.

CNC is typically obtained by calcining clay at around 800°C for a few hours [48] This thermal treatment is used to improve the chemical properties of the clay, supplementing the reactivity of the clay and the performance of cementitious materials when used in concrete as a supplementary component. It has high surface area and the ability to enhance the bond, thus enhancing the cohesiveness and workability of the cementitious mixture. The intention to incorporate these nanoparticles into the mortar was to evaluate its effect on its mechanical and physical properties, with a special focus on the minimisation of porosity and the enhancement of strength. Physical characteristics were obtained from the suppliers, whereas the chemical composition was obtained using XRF analysis. The characteristics of NS and CNC are depicted in Table 1. The sample of NS and CNC is shown in Figure 1.

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Table 1
Properties of NS and CNC.
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Figure 1
(a) Nano silica; (b) Calcined nano clay.

Glenium 51 superplasticizer was added to enhance the workability of the cement mortar mixes. It is a high-performance super plasticizer that increases fluidity without the need to add more water, a homogeneous and controllable mix that facilitates easy placement and better compaction. The addition of it to the mortar allowed to maintain the preferred consistency and flow, particularly in mixtures that included nano-silica and calcined nano-clay, which can otherwise increase the viscosity.

3. METHODS

The mortar mixtures were developed using a cement-to-sand ratio of 1:3, with cement partially substituted by varying proportions of NS and CNC, based on the mass of cement. The concentrations of NS (2–5%) and CNC (3–7%) have been identified based on prior research [49, 50].

The NS content varied between 2% and 5%, whereas the CNC ranged from 3% to 7%, Various water to binding agent (w/b) ratios, ranging from 0.30 to 0.50, have been used together with appropriate concentrations of superplasticizer (1.0% to 1.3%) to produce workable mixtures and attain the specified strength and durability properties. The control mixture (C1) did not incorporate any cement replacement, whereas the other mixtures (N1 to N8) consisted of NS and CNC in differing proportions. The same cement and sand proportion was used to create all mixes, and the other parameters were varied to examine their influence on mortar properties. Table 2 provides details on the mix compositions and identification.

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Table 2
Mix identification details.

4. TESTS CONDUCTED

The workability, setting time, strength, durability, and microstructural characteristics of the modified mortar mix were assessed through a series of experiments. The consistency test was conducted as per the IS 4031 (Part 4) [51] to identify the quantity of water that was needed to attain the standard consistency of the cement paste. The mortar was evaluated based on the flow table test as specified in IS 5512 [52] whereby the spread of the mortar was measured 25 table drops after. The flow value of this test implies the ease of handling and placement of the mortar. Compressive strength was measured at 7, 14, and 28 days using a compression testing machine in accordance with IS 4031 (Part 6) [53]. Vicat apparatus determined the setting time in accordance with IS 4031 (Part 5) [54] with the beginning and final setting times reflecting the hardening rate caused by nano-silica (NS) and calcined nano-clay (CNC) additions. Ultrasonic Pulse Velocity (UPV) (IS 13311 Part 1) [55] for density and homogeneity,

Mortar has the tendency to shrink due to loss of moisture with resulting volume reduction and cracking. The study adhered to the requirements provided in IS 4031 (Part 10) – 1988 [56]. Mortar specimens were prepared of 25 mm × 25 mm × 250 mm and cured them in water for seven days. Following the curing phase, initial length measurements were taken. To assess drying shrinkage, the samples were placed in an oven at 50°C until their length stabilized, after which the final length was measured and shrinkage determined. For the autoclave shrinkage test, the specimens were subjected to steam at 216°C and 2.1 MPa pressure for three hours. Lengths were measured before and after the autoclaving operation. The amount of water absorbed was calculated as per IS 2645 [57] to determine the permeability of the mortar. The durability performance was to be checked using the acid resistance, the specimens were immersed in a 3% sulphuric acid solution and the sulphate attack where the samples were immersed in 3% sodium sulphate solution over a period of 30 and 60 days [58]. Moreover, the microstructure of the mortar was scanned with the help of the scanning electron microscopy (SEM) to monitor the effect of NS and CNC on the internal matrix. Some of the laboratory test methods are represented in Figure 2.

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Figure 2
Laboratory test methods used in the study: (a) water saturation; (b) oven drying; (c) compressive strength test; and (d) autoclave process.

5. DISCUSSION OF EXPERIMENTAL FINDINGS

5.1. Properties of fresh mortar

The fresh properties of cement paste and mortar such as the consistency, setting time, and workability of the mentioned mixture largely depend on the NS and CNC particles. Table 3 shows the summary of the above- mentioned test results.

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Table 3
Fresh properties of mortar.

The presence of NS and CNC influences the cement mortar mixtures of fluidity and setting time. Table 3 shows that an increase in the proportions of NS and CNC causes a significant variation in both initial and final setting times. The initial and final setting time of the control mix (CM1) is 110 minutes and 240 minutes, respectively, and the consistency is 28%. Conversely, the NM8 mix, which contains 5% NS and 7% CNC, exhibits superior consistency at 35% and reduces the initial and final setting durations to 85 and 215 minutes, correspondingly.

This trend is similar to results of KUMAR et al. [39] which show NS improves early hydration because of its great specific surface area. This effect secures setting times by increasing the number of nucleation points for hydration products. Studies [38, 39, 40] similarly found that adding nano-sized particles, such NS, accelerates hydration reactions and lowers setting times because of their pozzolanic nature and high reactivity. This behavior indicates that reactivity of NS and CNC particles increases hydration process speed. The results from the flow table test reveal the variation of workability; high concentration of NS and CNC result in low flowability as a result of the increase of water demand.

The Table 3 results showed that workability was enhanced to a certain degree due to the use of NS and CNC. Mixtures of 5% NS + 7% CNC content showed higher flow percentage compared to the conventional mix indicating a higher fluidity. However, the further increment of the proportions of NS and CNC led to a moderate decrease in the flow percentage, which is likely to be caused by the high-water need associated with the fine particles of the NS and CNC. This is consistent with earlier research reports [39], which showed that nano clays can enhance fluidity by filling gaps in the mixture in addition to reducing friction between the particles.

5.2. Hardened properties of mortar

Table 4 summarizes the various experiments that were conducted to evaluate the hardened properties of the nano-modified mortar mixes.

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Table 4
Hardened properties of NS and CNC blended mortar mixes.

The test findings suggests that the addition of NS and CNC positively affected the strength and internal quality of cement mortar. The conventional mix (CM1) exhibited compressive strength values of 22.10 MPa at 7 days and 36.40 MPa at 28 days. The strength values of all nano-modified mixtures were better at 28 days with a range of 37.05 Mpa to 39.62 Mpa, as depicted in Figure 3. The optimal performance was noted for the mixture which includes 4% NS and 6% CNC. This behavior suggests that nanoparticles enhance hydration process which provide a denser cement matrix when utilized in appropriate amounts [59, 60]. In the early stage, compressive strength ranged between 21.50 to 24.25 Mpa. Certain mixtures exhibited only modest enhancement or a slight reduction in early strength, attributable to the augmented surface area of nanomaterials that raises water requirements and influences early hydration if dispersion is inadequate.

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Figure 3
Strength evolution of mortar mixes with curing age.

Improved matrix density resulted in an increase in compressive strength to NM7. The minor decrease in NM8 may be attributed to the presence of an excessive amount of nanomaterials, which can result in weaker bonding and poor dispersion. These trends have been observed in earlier studies, with moderate levels of nanomaterials enhancing strength, and high levels leading to the reduction of strength [61, 62, 63].

The flexural strength data at 28 days exhibited a consistent trend. The control mix observed a flexural strength of 5.20 MPa, while the nano-modified mortars demonstrated values ranging from 5.81 MPa to 7.05 MPa. The improved flexural performance means higher resistance against crack initiation and propagation. This has been enhanced by better packing of the particles and strengthening of the cement matrix to allow uniform distribution of stress when subjected to a bending load [64, 65].

Figure 4 depicts the UPV test results on various nano-modified mortar mixes. At 28 days, the UPV was 3.97 km/s to 4.35 km/s, indicating that the range of all mixtures fell under the good to very excellent category of the group of mixtures as shown by IS 13311 (Part 1). The reduced UPV value of the control mix represents an indication of a relatively porous composition of the mix but high values in nano-modified mixes represent an increase in density and internal consistency. Increased UPV values typically signify a reduction in internal voids and a more cohesive, dense matrix., which enhance the transmission of waves.

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Figure 4
UPV test results of mortar mixes.

The findings indicate that NS and CNC can substantially enhance the mechanical properties and internal integrity of cement mortar. The findings emphasize that proper proportions are essential, as an excess of nano-material content does not necessarily result in proportional enhancements. When accurately administered, NS and CNC collaborate to optimize the microstructure, enhance strength development, and elevate overall mortar quality.

5.3. Shrinkage test on mortar specimens

The drying shrinkage and autoclave shrinkage tests were carried out on mortar specimens to study their dimensional stability. The average drying shrinkage values of the mixes ranged from 0.056 to 0.065 mm/m, while the autoclave shrinkage ranged from 0.18 to 0.24 mm/m, as illustrated in Figure 5. A gradual reduction in shrinkage was noticed up to the NM3 mix (0.6%), after which a slight increase occurred for higher dosages. The reduction in shrinkage up to NM3 can be linked to the dense microstructure formed by the fine nano-particles, which help reduce water loss and pore spaces. Mix NM3 had the lowest shrinkage and this implies that it has a higher volume stability and less tendency of cracking as opposed to the CM.

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Figure 5
Shrinkage results of mortar mixes.

5.4. Durability performance of mortar mixes

5.4.1. Water absorption

The absorption of water was significantly lower in all mortar mixtures that contained calcined nano-clay (CNC) and nano-silica (NS) than in the standard mortar, as exhibited in Figure 6. The control mix had a water absorption value of 5.80, while the modified mixtures had values that ranged from 4.35 to 5.40 percent. The mixture of 4 percent NS and 6 percent CNC exhibited the lowest absorption, with a value of 4.35 percent. Absorption of water was also reduced because of reduced pore connectivity and a more condensed microstructure [63]. This resulted in a reduction in the capillary porosity, which in turn limited the migration of water across the mortar. The results confirmed that the incorporation of NS and CNC improves moisture ingress resistance, which is beneficial for enhancing the long-term durability of cement mortar.

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Figure 6
Comparison of water absorption values for mortar mixes.
5.4.2. Acid resistance test

The findings of the acid attack indicate that all mortar mixes were deteriorated over time due to exposure to an acidic environment, which was measured by gains in weight loss and reduction of strength with time. The weight reduction of the control mix (CM1) was 1.84 after 30 days and 2.56 after 60 days. Mortars containing NS and CNC had slightly reduced weight loss values throughout the two exposure durations, ranging from 1.68 to 1.98 percent at 30 days and 2.30 to 2.62 percent at 60 days, as depicted in Figure 7. The inclusion of nanomaterials facilitated the reduction of surface disintegration caused by acid infiltration [34].

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Figure 7
Effect of acid exposure on weight loss and strength degradation of mortar mixes.

The same trend was observed in strength degradation. The control mortar had loss in strength of 2.30 percent after 30 days and 5.21 percent after 60 days and the nano-modified mixes had loss per strength of 2.10 percent-2.47 percent after 30 days and 4.87 percent-5.13 percent after 60 days. Though all the mixes had higher degradation with long-term exposure mortars with NS and CNC had higher percentages of their original strengths, relative to the control mixture.

The enhanced acid resistance of the nano-modified mortars may be explained by the fact that fine particles of NS and CNC make the microstructure more dense and make the pores less connected and prevent the acid penetration. The refined matrix inhibits the leaching of calcium-based compounds and also inhibits the degradation process [39, 66]. The findings would indicate that the addition of NS and CNC would increase the resistance of cement mortar against the acidic conditions, resulting in an increase on its durability when it is subjected to a long-term acidic condition.

5.4.3. Sulphate attack

The sulphate attack results showed an increased resistance of cement mortar when NS and CNC were incorporated related to the conventional mix. After 30 days of exposure the weight loss of the control mix (CM1) was found to be 1.6% and the lower values between 1.22 to 1.50% were recorded for the modified mixes as shown in Figure 8. With an increase in the exposure duration to 60 days, weight loss increased for all mixes, however, mortars consisting of NS and CNC continued to have better performances with values between 1.68% and 2.05% compared to 2.2% for the control mix.

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Figure 8
Effect of sulphate exposure on weight loss and strength degradation of mortar mixes.

The trend was similar for degradation of strength. The strength losses for the conventional mortar were 6.2% and 7.6% at 30 and 60 days, while strength losses for the nano-modified mortars varied between 4.7% and 5.8% and 5.3% and 7.1% at 30 and 60 days, respectively. Among the modified mixes, mixes with moderate content of nano-material exhibited lower strength loss indicating better resistance against sulphate penetration.

The intensified sulphate resistance can be attributed to the development of a dense microstructure as a result of the fine particle size of NS and CNC. This microstructure reduces the permeability and also restricts the access of sulphate ions. This leads to reduced formation of expansive reaction products and better strength retention. The results confirmed that the significant effect of the addition of NS and CNC on the sulphate durability of cement mortar under prolonged.

5.5. SEM examination of nano modified and control mortar mixes

The control mix and the optimal mix (4% NS + 6% CNC) were chosen to compare microstructural characteristics. The SEM images of conventional and nano-modified mortar are exhibited in Figures 9(a) and 9(b). The SEM micrograph of the control cement mortar shows a microstructure with irregular and angular particles and rough and non-uniform surface texture. The matrix is loosely packed and capillary pores and inter-particle voids are seen clearly, indicating that the matrix is not fully dense. Hydration products are only in limited amounts and unevenly spread so the cementitious network is discontinuous. In several regions weak particle contacts and micro-cracks are obvious which are indicative of poor bonding between the cement paste and sand particles. Such a porous and heterogeneous microstructure is typical of conventional mortar and accounts for the relatively lower mechanical strength and reduced resistance to long-term durability-related deterioration.

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Figure 9
SEM photograph (a) control mix; (b) 4% nano-silica and 6% calcined nano-clay mix.

In contrast, the mortar with 4% nano-silica and 6% calcined nano-clay has a very fine and compact microstructure. Nano-silica particles are efficient at filling in micro- and nano-sized pores, and serving as the nucleation sites for further reaction products and formation of a more continuous matrix. The plate-like morphology of calcined nano-clay also favors the packing of particles and also plays a role in the formation of a denser interfacial transition zone between the binder and fine aggregate [62]. In the result, there are much less porosity, good matrix continuity and micro-defects or cracks in the microstructure. The combined action of the nano-silica and calcined nano-clay makes an obvious effect on the improvement of internal densification, the reduction of weak zones and the strengthening of the bonding of particles. These microstructural improvements are directly related to the enhancement in mechanical strength and durability performance of the nano-modified mortar in comparison to the conventional mix.

5.6. Economic feasibility analysis

The inclusion of NS and CNC slightly raises the initial mortar cost since nanomaterials are expensive compared to traditional cement materials. The modified mortar however demonstrated enhanced strength and durability, which can help in reducing the cost of repair and maintenance in the service life of the structure [41, 50]. The optimum mix provided a superior overall performance at a minimal level of addition of nano-material, which is more practical and efficient. These changes in water absorption and resistance to acid and sulphate attack have shown the modified mortar to be able to do better in the conditions of moisture and resistance to acid and sulphate attack. This makes it suitable when used in projects such as municipal buildings, water infrastructure and repair works where the durability is a key consideration. Consequently, while the initial material expense is significantly increased, the enhanced long-term performance could lead to economic advantages in actual construction applications.

6. CONCLUSIONS

This study investigated the impact of NS and CNC on the fresh, mechanical, durability and microstructural characteristics of cement mortar of 1:3 mix proportion. Based on the experimental observation, the following conclusions are drawn:

  1. The incorporation of NS and CNC had increased the water demand of the mortar due to their high fineness but by using a suitable superplasticizer the workability of all the mixes was ensured. The modified mortars exhibited lower initial and final setting time than the conventional mix suggesting accelerated hydration in the presence of nanomaterials.

  2. Mortars with NS and CNC had better compressive and flexural strength especially at 28 days. Mixes with moderate values of NS and CNC showed better behavior compared to the control mix and mixes with higher replacement levels emphasizing the importance of balancing nano-material dosage.

  3. Durability performance was much improved in nano-modified mortars. Lower weight loss and reduced strength degradation were observed under acid and sulphate exposure, confirming better resistance to aggressive environments. Water absorption values were also lowered, which means the matrix is more dense and less permeable.

  4. UPV results showed superior internal quality and homogeneity of the modified mortars as compared to the conventional mix. All nano-modified mixes were in the good to excellent quality range, indicating the improved compactness.

  5. SEM analysis showed that the conventional mortar had a porous and non-uniform microstructure, which was different from the mortar that contained NS and CNC with a dense, compact and well-connected matrix, containing less empty space and micro-cracks. This microstructural refinement is the source behind the observed improvements in strength and durability.

  6. Overall, the combined application of NS and CNC was proved to be effective in improving the performance of the cement mortar. These materials can be regarded as promising additives for the production of high-quality and long-lasting mortar for advanced construction applications.

6.1. Future research directions

Despite the fact that this research shows the positive impacts of NS CNC on cement mortar performance, additional studies should be done to elaborate and intensify these results. Further research can be done on testing the long-term stability of nano-modified mortars when subjected to prolonged exposure to aggressive factors like marine conditions, cyclic wet-dry conditions, and temperature fluctuations. The blending of nanoparticles with additional supplemental cementitious materials requires investigation to enhance comprehension of their potential in creating more sustainable and high-performance mortar systems. As well, the dispersion mechanisms of nanomaterials and how they interact with various admixtures should be studied in some detail to help optimize mix design and enhance consistency in large scale applications. It is also possible to investigate the effect of NS and CNC on shrinkage cracking, creep behaviour, and bond strength in masonry and repair applications.

7. ACKNOWLEDGMENTS

The authors declare that there are no acknowledgements.

8. DATA AVAILABILITY

The data that support the findings of this study are available from the corresponding author upon reasonable request.

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Publication Dates

  • Publication in this collection
    29 June 2026
  • Date of issue
    2026

History

  • Received
    03 Feb 2026
  • Accepted
    22 May 2026
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