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Article

Molecular Dynamics Simulation of CNT Reinforced Cement: A Step Toward Sustainable Construction

by
Rosario G. Merodio-Perea
1,
María-José Terrón-López
2 and
Isabel Lado-Touriño
2,*
1
On Line Department, Creative Campus, Universidad Europea de Madrid, 28006 Madrid, Spain
2
Department of Engineering, School of Architecture, Engineering, Science and Computing, Universidad Europea de Madrid, 28670 Villaviciosa de Odón, Spain
*
Author to whom correspondence should be addressed.
Sustainability 2025, 17(7), 3185; https://doi.org/10.3390/su17073185
Submission received: 11 February 2025 / Revised: 18 March 2025 / Accepted: 31 March 2025 / Published: 3 April 2025
(This article belongs to the Special Issue Integrating Sustainability in Engineering: Towards a Sustainable Future)
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Abstract

This study explores the potential of carbon nanotubes (CNTs) to enhance cement mechanical properties, aiming to develop more sustainable materials and reduce the industry’s carbon footprint. Using molecular dynamics (MDs) simulations, the effect of pristine and carboxyl-functionalized single-walled CNT incorporation on the mechanical properties of 11 Å tobermorite, a model for calcium–silicate–hydrate (CSH), was analyzed. The results demonstrated a significant increase in the elastic modulus (E) of the composite, with CNT content directly influencing this enhancement. Specifically, E increased from 77.05 GPa to 81.93 GPa upon the incorporation of pristine CNTs and further increased to 97.87 GPa with the introduction of carboxyl-functionalized CNTs. Composites containing functionalized CNTs exhibited a more pronounced increase in E, as the carboxyl groups formed hydrogen bonds with the tobermorite structure, thereby reinforcing interactions and improving mechanical properties. Thus, increasing functionalization allows for lower reinforcement content, reducing costs and CNT aggregation, as observed in experimental studies. These findings underscore the potential of functionalized CNTs to strengthen cementitious materials, offering an alternative to traditional additives. This approach could contribute to reducing the carbon emissions associated with cement production, thereby supporting the development of more sustainable and environmentally friendly cement alternatives.

1. Introduction

The cement industry is a cornerstone of global infrastructure development but is also one of the largest contributors to greenhouse gas emissions, accounting for nearly 8% of global CO2 emissions [1]. Since the 1960s, emissions from cement production have increased dramatically, more than doubling since the early 2000s. Currently, the world produces over four billion metric tons of cement annually. These emissions stem primarily from the energy-intensive clinker production process and the chemical reactions involved in calcination [2]. Additionally, the use of fossil fuels in cement kilns significantly contributes to the industry’s carbon footprint. As urbanization and infrastructure demands continue to rise, the need to balance construction needs with environmental sustainability has become increasingly urgent. It is imperative that the cement industry adopts more sustainable practices and explores innovative alternatives to reduce its environmental impact while simultaneously meeting the growing demands for global infrastructure.
To address this challenge, there is an increasing emphasis on developing alternative materials and enhancing the performance of existing ones. Improving the mechanical properties and durability of cementitious materials can reduce the volume of the cement required, thereby directly lowering emissions [3]. Additionally, the integration of innovative solutions, such as supplementary cementitious materials [4], recycled industrial by-products [5,6], and nanotechnology-based reinforcements [7,8,9], including carbon nanotubes (CNTs) [10,11], into cement paste offers substantial potential for reducing clinker content and enhancing the overall sustainability of cement. These advancements are pivotal in aligning the cement industry with global targets for carbon neutrality and greener construction practices. By optimizing formulations and leveraging novel technologies, researchers and industry stakeholders can significantly mitigate the climate impact of cement production while meeting the growing demand for durable and efficient infrastructure.
The incorporation of CNTs in concrete offers significant advancements in sustainability within the construction industry. By enhancing the mechanical properties of concrete, such as compressive, tensile, and flexural strength, CNTs enable a reduction in the amount of cement required [12,13,14]. This reduction is decisive, as cement production is a major source of CO2 emissions, as mentioned earlier. Consequently, using less cement directly contributes to lowering the carbon footprint of construction projects. Among the properties enhanced by the addition of CNTs to cement are the following: compressive and flexural strength, with improvements of up to 60% and 43.4%, respectively [15,16,17]; and durability [18], including carbonation resistance [11,12,19,20], chloride penetration resistance [21], water absorption [22], and freeze–thaw cycles [19]. This enhanced durability extends the lifespan of concrete structures, reducing the frequency of repairs and replacements, which in turn conserves resources and minimizes waste generation. The reduced permeability to these substances is attributed to the ability of CNTs to decrease porosity and improve the microstructure of concrete [23,24]. The role of CNTs in enhancing cement mechanical properties, particularly in preventing crack propagation and increasing fracture toughness, has been widely discussed in the scientific literature. For instance, Lan et al. [25] found that adding 0.15 wt% of CNTs to concrete increased the cracking time by 42.1% under semi-closed conditions and 41.2% under closed conditions. Additionally, CNTs improved concrete initiation fracture toughness by 31.0%, unstable fracture toughness by 32.4%, and fracture energy by 24.6%. Bogas et al. [26] found that adding CNTs to concrete helped mitigate the negative effects of both natural and artificially induced cracks on its durability. The beneficial effects of CNTs were most pronounced in the areas immediately surrounding the cracks in the concrete. Hassan et al. [27] attributed the improved mechanical properties to CNTs acting as bridges across microcracks in the concrete structure, as observed through SEM analysis. In a recent study, Joshi [28] found that microscopic analysis showed CNTs were adequately distributed in the concrete, helping to bridge and delay the propagation of both micro and macro cracks. Moreover, CNT-reinforced concrete exhibits self-sensing capabilities, allowing for real-time structural health monitoring [29,30]. This smart property enables early detection of damage, thereby preventing catastrophic failures and reducing maintenance costs. On the other hand, CNTs’ ability to improve thermal conductivity in concrete can enhance energy efficiency in buildings by providing better thermal insulation [31].
However, the production of CNTs remains energy-intensive [11], and their environmental impact during large-scale manufacturing requires further investigation. Addressing these challenges through green synthesis methods or improved scalability could enhance the sustainability profile of CNTs, making them a promising option for creating more resilient, efficient, and environmentally friendly construction materials.
The primary challenge in using CNTs as reinforcements in cementitious matrices lies in achieving their homogeneous distribution, as inadequate dispersion negatively impacts the mechanical properties of the resulting materials [11,14,31]. CNTs naturally tend to agglomerate and form bundles due to van der Waals forces, which hinder their proper integration within the cement and reduce their adhesion to the matrix. To overcome this issue, various strategies have been developed. These approaches often involve the use of ultrasonic energy in conjunction with functionalization agents that modify the CNT surfaces [32]. One effective method is the introduction of carboxyl groups on the CNT surface, which increases their hydrophilicity and promotes the formation of chemical bonds with the cementitious matrix. This modification significantly improves adhesion between the CNTs and the matrix [33,34].
In addition to studying the properties of materials from an experimental perspective, simulation techniques, such as molecular dynamics (MDs), can be utilized. These methods provide valuable insights into the relationship between material properties and their atomic structure. Numerous studies have investigated the properties of pure cement and cement reinforced with carbonaceous nanostructures using MDs techniques, revealing that the properties of cement are significantly enhanced when reinforced with CNTs. Cui et al. [35], through a study combining experimental data and MDs simulations, reported that incorporating CNTs into low-carbon concrete enhanced 28-day compressive strength by 27.8% and flexural strength by 16.7%. They attributed the enhancement to CNTs improving the interfacial transition zone, promoting the formation of ettringite and gibbsite, which enhanced hydration. MDs simulations confirmed that CNTs acted as seeds at the interphase, reducing its width and strengthening bonding by facilitating the formation of these phases. Zhao et al. [36] found that incorporating CNTs into the concrete matrix enhanced the Young’s modulus to 35 GPa and the final strength to 35.38 MPa. MDs simulations effectively captured these improved mechanical properties. Roopa et al. [37] reported that increasing the CNT content up to 0.5% by weight in the cement matrix enhanced mechanical properties by approximately 12% while exceeding this threshold led to a 5% reduction due to nanotube agglomeration. They also found that higher CNT proportions also improved electron mobility, as shown by the density of states analysis in simulations. Qin et al. [38] observed that adding up to 0.5% CNTs improved mechanical properties, while excess CNTs caused agglomeration and strength reduction. MDs simulations estimated a maximum Young’s modulus of 46 GPa for the 0.5% CNT-reinforced composite. The CNTs also contributed to crack bridging, further enhancing the material’s durability. Sindu et al. [39] found that incorporating CNTs into the CSH system enhanced strength, elastic modulus, and shear modulus while increasing ductility. They quantified the transformation from brittleness to ductility, enabling the design of cementitious composites with tailored mechanical properties. Yu et al. [40] demonstrated through MDs simulations that CNTs provide superior reinforcement to concrete compared to other fibers. Their study analyzed the CNT–cement structure and its mechanical behavior under high temperatures, highlighting the nanoscale interactions between CNTs and the CSH phase. Most MDs studies were based on the hypothesis that CNTs enhance the interfacial strength of the cement matrix by promoting adhesion between components. Thus, these methods are ideal for investigating these phenomena at the atomic level, as they enable detailed simulations of atomic interactions and material behavior at the nanoscale.
In our previous research, we explored the interaction between tobermorite and CNTs functionalized with different numbers of carboxyl groups using MDs simulations [41]. This study highlighted the significant improvements in mechanical properties brought about by the addition of both functionalized and pristine CNTs to the tobermorite structure. The functionalization of CNTs, in particular, was found to enhance their interaction with the cementitious matrix, further contributing to the observed improvements. Building on these previous findings, this study explores how the number and degree of CNT functionalization affect the mechanical properties of tobermorite using MDs simulations. The results provide atomic-scale insights into CNT–cement interactions, enabling a detailed analysis of interfacial bonding and the role of functionalization in mechanical reinforcement. By systematically varying CNT quantity and surface functional groups, we assess their impact on material performance. Given that excessive CNT concentrations can cause aggregation, compromising mechanical properties and increasing costs, this research aims to identify the key CNT characteristics that optimize cement reinforcement while minimizing CNT content. Previous studies have shown promising results, highlighting the importance of these factors in achieving superior mechanical properties [36].

2. Materials and Methods

In this section, the models, simulation methods, and computational techniques employed to examine the influence of CNT concentration and functionalization on the mechanical properties of tobermorite are outlined.

2.1. Models

To study the effect of CNT quantity on the mechanical properties of 11 Å tobermorite, CNTs (2, 2) with a diameter of 2.71 Å and a length of 9.84 Å were used. These CNTs were functionalized with either two or four carboxyl groups. The CNTs (2, 2) were selected for their small diameter, which minimizes structural distortion within the tobermorite matrix. Table 1 provides an overview of the nomenclature and the number of CNTs in each model. To maintain a consistent weight ratio across all systems, the number of CNTs in the models with two carboxyl groups differs from that in the other two cases. The number in parentheses in the right column indicates the weight percentage of CNTs in each model.
The amorphous cell module of the Materials Studio 7.0 software [42] was utilized to incorporate the CNTs into the tobermorite crystal and construct the simulation cells. Initially, multiple cells were constructed, and the ones exhibiting the most uniform CNT distribution were selected for mechanical property calculations. Figure 1a,b depict the tobermorite matrix structure with 3 CNTs and 12 CNTs, respectively.
Figure 2 shows the structural characteristics of the CNTs analyzed in this study, including (a) pristine CNTs, (b) CNTs functionalized with two carboxyl groups, and (c) CNTs functionalized with four carboxyl groups.

2.2. Calculations

MDs calculations were conducted using the Forcite module of Materials Studio 7.0 software to calculate the mechanical properties of the models. The simulations were carried out in the NPT ensemble (constant particle number N, pressure P, and temperature T), with a temperature of 298 K maintained by a Nose–Hoover thermostat [43] and a pressure of 1 × 10−4 GPa using a Berendsen barostat [44]. The simulations lasted between 1000 and 2000 ps, with a time step of 1 fs, which was sufficient to achieve equilibrium in the system’s potential energy.
The force field used to calculate the interactions between tobermorite and CNTs was the Condensed-Phase Optimized Molecular Potential for Atomistic Simulation Studies (COMPASSII) force field [45]. COMPASSII, based on ab initio calculations, accurately describes the structure and properties of condensed-phase molecules and systems across a broad range of temperatures and pressures. This force field has been successfully applied in simulations of systems containing CNTs and various cement-derived materials [46,47,48,49,50].
To calculate the mechanical properties (Young’s modulus E, Poisson’s ratio ν, shear modulus G, and bulk modulus K), the elastic method was employed. This methodology determines the system response to an imposed strain by evaluating the second derivative of the potential energy with respect to strain. The relaxation process under the applied strain was analyzed using the Hessian matrix. The approach was implemented on the final ten frames of the MDs trajectory, averaging the elastic constants, K and G, across all frames. Comparable techniques have been adopted in previous studies, yielding results that closely align with experimental measurements of the mechanical properties of both CSH gel and CNT-reinforced polymers [49,51,52]. These studies validate the accuracy and reliability of the computational approaches used in this research.
To determine the mechanical properties of the composite materials, the Voigt–Reuss–Hill (VRH) approximation [53] was employed. This method offers a more precise estimation of the elastic moduli by averaging the upper and lower bounds of material stiffness. Through this approximation, E and ν were calculated using the following equations, which incorporate the values of K and G obtained from the MDs simulations.
E = 9 · K · G 3 · k + G
ν = 3 · K − 2 · G 2 3 · k + G

3. Results and Discussion

3.1. Mechanical Properties

In this section, the mechanical properties of the tobermorite–CNT composites are analyzed, with a specific focus on how the number and degree of CNT functionalization influence the values of K, G, E, and ν.
Table 2 presents the calculated values of K, G, E, and ν, derived using Equations (1) and (2) based on the MDs method outlined earlier.
The results in Table 2 reveal a clear trend of improved mechanical properties with the incorporation of CNTs and their functionalization with carboxyl groups. Pristine tobermorite shows the lowest values for K (43.99 GPa), G (31.98 GPa), and E (77.05 GPa). The addition of pristine CNTs (PTCNT3, PTCNT7, PTCNT12) improves the mechanical properties, with the enhancement directly proportional to the CNT content, emphasizing the reinforcing effect of these nanostructures. Furthermore, functionalization with carboxyl groups further amplifies this enhancement by improving the interfacial bonding between the CNTs and the tobermorite matrix. Overall, the data highlight the synergistic effects of CNT quantity and functionalization, demonstrating that optimal mechanical performance is achieved with a combination of high CNT content and extensive carboxyl functionalization. Another important conclusion drawn from these data is the following: as shown in Table 1, the CNT weight percentages across all models are quite similar. However, even a slight increase in the number of CNTs and, more significantly, their degree of functionalization results in improved mechanical properties. The key factor appears to be the enhanced interactions at the interface between carboxyl groups and tobermorite atoms. This suggests that even at low CNT concentrations, a high surface functionalization density may be sufficient to improve the mechanical properties of cement. This finding is particularly significant, as high CNT concentrations can increase material costs and lead to CNT agglomeration, which negatively impacts mechanical properties. Therefore, the optimal solution would be to use highly functionalized CNTs at low concentrations.
Several authors have investigated the moduli of tobermorite using molecular MDs simulations, obtaining results consistent with those presented in this study. Bhuvaneshwari et al. [46] calculated the moduli for three types of tobermorite (9 Å, 11 Å, and 14 Å) as well as jennite, with their findings aligning with the values reported here for 11 Å tobermorite. Similarly, Arar [50] obtained comparable results, further confirming the consistency of these findings. Previous studies have also explored the mechanical properties of tobermorite reinforced with both pristine [52,54] and functionalized CNTs [39,55,56,57,58]. These studies report significant improvements in the tensile strength of CNT-reinforced CSH, particularly along the CNT axis, regardless of functionalization, when compared to unreinforced CSH. The results of this study are in good agreement with these previous findings.
To present the results more clearly, Figure 3 shows the E values obtained for each type of structure. It can be observed that E increases with higher quantities of both pristine and functionalized CNTs. This enhancement may result from the stronger interaction between the matrix and the reinforcement as more CNTs are incorporated. Furthermore, the functionalization of the CNTs enhances their interaction with tobermorite through the introduced functional groups. The greater the number of functional groups, the stronger the interaction.
It is important to note that experimentally measured values are generally lower than those predicted by theoretical models. This discrepancy can be attributed to factors such as defects, impurities, and microstructural variations in real materials, which are not considered in idealized calculations. It should be noted that in real systems, increasing the concentration of CNTs in a cement matrix can negatively affect mechanical properties due to factors such as agglomeration, increased porosity, interference with hydration, weak interfacial bonding, and reduced workability. While our ideal models do not account for these effects, they demonstrate that increasing the number of interaction points between CNTs and cement can enhance the material’s strength. Experimentally, the challenge lies in determining the optimal conditions to use the appropriate amount of functionalized CNTs, balancing reinforcement with avoiding the negative effects mentioned, and ensuring the material mechanical properties are not compromised.
Vélez [59] explored the relationship between porosity and E in various clinker phases and cementitious components. His findings revealed that materials with zero porosity exhibit higher modulus values, highlighting the significant impact of porosity on mechanical properties. As porosity increases, the elastic modulus decreases due to the presence of voids, which weaken the material structure. Jennings [60] introduced a colloidal model consisting of globular CSH particles, which can be arranged into two distinct structures depending on their packing density: high-density CSH (HD CSH) and low-density CSH (LD CSH). A practical approach to quantifying the correlation between E and porosity involves applying the equation formulated by Knudsen and Helmuth [59]. This equation provides a means to calculate the elastic modulus as a function of porosity, allowing for a more accurate prediction of mechanical properties in materials with varying levels of porosity. By incorporating porosity into the calculations, this approach helps bridge the gap between theoretical predictions and experimental measurements, offering a more realistic assessment of material performance:
E = E 0 e − 3.4 p
In this equation, E0 represents the elastic modulus in the absence of porosity (calculated E), while p denotes the porosity. The coefficient 3.4 is an empirical factor derived from fitting various experimental datasets [61], accounting for the impact of porosity on the material’s mechanical properties.
Table 3 presents the E values derived from the calculated E0 values in Table 2, using Equation (3). These calculated values account for the average porosities of HD and LD structures, with average porosities of 0.26 and 0.36, respectively, as mentioned earlier. This approach provides a more realistic assessment of the material performance, considering the inherent porosity in HD and LD structures.
As shown in Table 3, an increase in porosity significantly reduces the E values. For tobermorite, our calculated values closely align with those reported by Fu et al. [62]: 31.45 GPa and 18.11 GPa for the HD and LD structures, respectively. Similarly, Arar [50] reported values of 15 GPa (HD) and 25 GPa (LD), while González et al. [63] found values of 32.2 GPa (HD) and 16.3 GPa (LD).
Experimental measurements of E for HD and LD structures have also been conducted by Constantinides [64] and Keinde [65] using nanoindentation techniques. Their results yielded values ranging from 21.7 GPa (LD) to 29 GPa (HD), further validating the calculated results and highlighting the impact of porosity on the mechanical properties of tobermorite. However, it is important to note that in real materials containing CNTs, the elastic modulus may exceed the values calculated using Equation (3). This is due to the pore-sealing effect of CNTs, which can reduce the material’s overall porosity and enhance its mechanical properties. As previously mentioned, the incorporation of CNTs, especially when functionalized, can significantly improve the interaction between the CNTs and the tobermorite matrix, leading to better load transfer and higher elastic modulus values. Overall, these findings underscore the critical role of porosity in determining the mechanical properties of tobermorite and highlight the potential of CNT reinforcement to enhance these properties further.

3.2. Hydrogen Bond Analysis

CNTs functionalized with COOH groups can form hydrogen bonds (H-bonds) with the oxygen atoms in tobermorite. Several studies [39,66,67,68] have highlighted a positive correlation between the mechanical performance of cement matrices reinforced with carbon-based nanostructures and the interactions, both chemical and non-bonding, that occur at the interface between the two materials.
Table 4 presents the average number of hydrogen bonds (NHB) formed between the CNTs and the tobermorite crystal, as well as the average bond length. The presence of H-bonds produces a strong interaction between the functionalized CNTs and the tobermorite matrix, contributing to the enhanced mechanical properties observed in the reinforced material. The criteria used to define a H-bond were as follows: a distance of less than 2.5 Å between the hydrogen atom of the donor group (D) and the oxygen atom of the acceptor group (A), and a D-H-A angle greater than 90°. Hydrogen bonds were analyzed from the last 10 frames of the models, which were also used to calculate the mechanical properties.
The analysis of the data in Table 4 reveals several key insights. First, increasing the functionalization of CNTs with carboxyl groups and incorporating a higher number of CNTs into the tobermorite crystal significantly enhances the number of H-bonds at the interface. This indicates that both functionalization and CNT concentration are critical in strengthening the interaction between the reinforcement and the matrix. As functionalization increases, the number of H-bonds also rises, suggesting that the carboxyl groups on the CNTs facilitate stronger and more numerous interactions with the oxygen atoms in the tobermorite matrix. Furthermore, adding more CNTs to the matrix amplifies this effect, leading to a higher total number of H-bonds.
Interestingly, the slight increase in H-bond length with a higher number of bonds suggests that structural adjustments within the crystal lattice may be occurring. These adjustments, possibly due to steric or spatial constraints as more CNTs are incorporated, result in marginally longer bonds. Despite this small increase in bond length, the overall number of H-bonds remains crucial in enhancing the interaction at the interface.
The increase in NHB with higher functionalization and CNT concentration indicates that these factors significantly strengthen the interaction at the interface, likely contributing to the improved mechanical properties of the composite material, as shown in Table 2 and Figure 3. Higher CNT content and functionalization lead to better mechanical performance, including an increased E.
Overall, these findings emphasize the potential of optimizing CNT functionalization and concentration to improve the mechanical properties of composite materials. By carefully controlling these factors, it is possible to achieve materials with superior mechanical strength and performance, making them ideal for advanced engineering applications.
Figure 4 shows the H-bonds, depicted as black dashed lines, formed between tobermorite and a CNT functionalized with four COOH groups.
The results of this study highlight the considerable potential of CNTs, especially when functionalized with higher numbers of carboxyl groups, in improving the mechanical properties of cementitious materials. By improving the elastic modulus and reinforcing interactions at the interface, CNTs contribute to the development of composites with superior performance and durability. These improvements allow for the reduction in cement volume required in construction, directly addressing the high carbon footprint of the cement industry. Furthermore, this work underscores the importance of MDs simulations in understanding the atomic-scale interactions that govern macroscopic properties.

4. Conclusions

Using MDs simulations, this study demonstrates the effectiveness of CNTs as reinforcements for cementitious materials, particularly when functionalized with carboxyl groups. The results indicate that, at similar CNT weight percentages, a higher density of functional groups leads to greater improvements in mechanical properties. This suggests that optimizing functionalization could be a key strategy for enhancing reinforcement efficiency while minimizing material aggregation and reducing costs. The main conclusions are as follows:
  • The incorporation of CNTs into the tobermorite structure significantly enhances the elastic modulus of the composite. Functionalized CNTs exhibit a stronger effect due to hydrogen bond formation between carboxyl groups and the matrix, reinforcing interfacial interactions.
  • A direct correlation is observed between the density of functional groups and mechanical reinforcement. Increasing the degree of CNT functionalization enhances mechanical performance without requiring higher CNT concentrations, enabling the design of optimized reinforcement strategies with reduced material costs and aggregation issues.
  • Structural parameters such as CNT length, diameter, and alternative functional groups (e.g., amino or epoxy) should be investigated to further improve CNT dispersion and reinforcement efficiency in cementitious matrices. Additionally, combining CNTs with other nanomaterials, such as nanoparticles or fibers, could lead to hybrid reinforcement systems with superior mechanical and durability properties.
  • From a computational perspective, coarse-grained MDs simulations could address the limitations of all-atom MDs models (small systems, short calculation times, presence of defects, porosity, etc.), allowing the study of larger system sizes and longer time scales while preserving essential insights into the mechanical behavior of cement–CNT composites.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/su17073185/s1.

Author Contributions

Conceptualization, I.L.-T.; methodology, M.-J.T.-L.; software, R.G.M.-P.; validation, R.G.M.-P.; investigation, I.L.-T. and R.G.M.-P.; data curation, M.-J.T.-L. and R.G.M.-P.; writing—original draft preparation, R.G.M.-P.; writing—review and editing, I.L.-T. and M.-J.T.-L. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

The original contributions presented in this study are included in the article/Supplementary Materials. Further inquiries can be directed to the corresponding author.

Conflicts of Interest

The authors declare no conflicts of interest.

References

  1. Cheng, D.; Reiner, D.M.; Yang, F.; Cui, C.; Meng, J.; Shan, Y.; Liu, Y.; Tao, S.; Guan, D. Projecting future carbon emissions from cement production in developing countries. Nat. Commun. 2023, 14, 8213. [Google Scholar] [PubMed]
  2. Nikolakopoulos, A.; Steriotis, T.; Charalambopoulou, G.; Karagiannakis, G.; Dimitrakis, D.; Michalis, V.; Katsiotis, M. Reducing carbon emissions in cement production through solarization of the calcination process and thermochemical energy storage. Comput. Chem. Eng. 2024, 180, 108506. [Google Scholar]
  3. Wang, W.; Chu, H.; Jiang, J.; Zhu, B. Enhancing mechanical performance and durability of high strength mortar with incineration bottom ash via Al2O3 micro-powder: An experimental study. J. Build. Eng. 2024, 89, 109268. [Google Scholar]
  4. Juenger, M.C.G.; Snellings, R.; Bernal, S.A. Supplementary cementitious materials: New sources, characterization, and performance insights. Cem. Concr. Res. 2018, 122, 257–273. [Google Scholar]
  5. Bergonzoni, M.; Melloni, R.; Botti, L. Analysis of sustainable concrete obtained from the by-products of an industrial process and recycled aggregates from construction and demolition waste. Procedia Comput. Sci. 2023, 217, 41–51. [Google Scholar]
  6. Navaratnam, S.; Tushar, Q.; Jahan, I.; Zhang, G. Environmental Sustainability of Industrial Waste-Based Cementitious Materials: A Review, Experimental Investigation and Life-Cycle Assessment. Sustainability 2023, 15, 1873. [Google Scholar] [CrossRef]
  7. Huseien, G.F. A Review on Concrete Composites Modified with Nanoparticles. J. Compos. Sci. 2023, 7, 67. [Google Scholar] [CrossRef]
  8. Reaches, Y. Nanoparticles as concrete additives: Review and perspectives. Constr. Build. Mater. 2018, 175, 483–495. [Google Scholar]
  9. Selima, F.A.; Amina, M.S.; Ramadana, M.; Hazem, M.M. Effect of elevated temperature and cooling regimes on the compressive strength, microstructure and radiation attenuation of fly ash–cement composites modified with miscellaneous nanoparticles. Constr. Build. Mater. 2020, 258, 119648. [Google Scholar]
  10. El-Gamal, S.M.A.; El-Hosiny, F.I.; Amin, M.S.; Sayed, D.G. Ceramic waste as an efficient material for enhancing the fire resistance and mechanical properties of hardened Portland cement pastes. Constr. Build. Mater. 2015, 154, 1062. [Google Scholar]
  11. Ahmad, J.; Zhou, Z. Properties of concrete with addition carbon nanotubes: A review. Constr. Build. Mater. 2023, 393, 132066. [Google Scholar]
  12. Jayakumari, Y.; Swaminathan, E.N.; Partheeban, P. A review on characteristics studies on carbon nanotubes-based cement concrete. Constr. Build. Mater. 2023, 367, 130344. [Google Scholar]
  13. Makul, N. Advanced smart concrete—A review of current progress, benefits and Challenges. J. Clean. Prod. 2020, 274, 122899. [Google Scholar]
  14. Bhatrola, K.; Maurya, S.K.; Kothiyal, N.C. An updated review on scientometric analysis and physico-mechanical performance of nanomaterials in cementitious composites. Structures 2023, 58, 105421. [Google Scholar]
  15. Mohsen, O.; Al Ansari, M.S.; Taha, R.; Al Nuaimi, N.; Taqa, A.A. Carbon Nanotube Effect on the Ductility, Flexural Strength, and Permeability of Concrete. J. Nanomater. 2019, 2019, 6490984. [Google Scholar]
  16. Ghogare, R.B.; Londhe, S.K.; Hande, S.A.; Bhosale, C.G.; Mane, A.V. To Improve the Strength of Concrete by Using Carbon Nanotubes (CNTs). Int. J. Res. Appl. Sci. Eng. Technol. 2023, 11, 6344. [Google Scholar]
  17. Güler, Ö.; Cacim, N.N.; Evin, E.; Yahia, I.S. The synergistic effect of CNTs-polymeric surfactant on the properties of concrete nanocomposites: Comparative study. J. Compos. Mater. 2020, 55, 1371–1384. [Google Scholar]
  18. Onaizi, A.M.; Huseien, G.F.; Lim, N.H.; Amran, M.; Samadi, F. Effect of nanomaterials inclusion on sustainability of cement-based concretes: A comprehensive review. Constr. Build. Mater. 2021, 306, 124850. [Google Scholar]
  19. Abdel-Mohti, A.; Soliman, E.; Shen, H. Effect of Adding Carbon Nanotubes on the Freeze-Thaw and Thermal Fatigue Resistance of Latex Modified Mortar. Fibers 2018, 6, 19. [Google Scholar] [CrossRef]
  20. Rodriguez, B.; Correa, E.; Arias, Y.P.; Quintero, J.H.; Calderon, J.A.; Mendoza, O.A. Carbonation study in a cement matrix with carbon nanotubes. J. Phys. 2019, 1247, 12024. [Google Scholar]
  21. Panagiotakopoulou, C.; Papandreopoulos, P.; Batis, G. Investigation of Corrosion Protection Through CNTs/CNFs Modified Cement Mortars. Curr. Nanomat. 2024, 9, 266. [Google Scholar]
  22. Sldozian, R.; Burakova, I.; Burakov, A.; Aljaboobi, Z.; Hamad, A.; Tkachev, A. The effect of multi-walled carbon nanotubes on mechanical properties and water adsorption of lightweight foamed concrete. Res. Eng. Struct. Mater. 2024, 10, 1139. [Google Scholar]
  23. Singh, N.B.; Rai, S. Properties of cementitious materials in presence of nano carbon. Mater. Today Proc. 2020, 29, 999–1005. [Google Scholar]
  24. Wang, J.; Dong, S.; Pang, S.D.; Zhou, C.; Han, B. Pore structure characteristics of concrete composites with surface-modified carbon nanotubes. Cem. Concr. Compos. 2022, 128, 104453. [Google Scholar]
  25. Lan, Y.; Zheng, B.; Shi, T.; Ma, C.; Liu, Y.; Zhao, Z. Crack resistance properties of carbon nanotube-modified concrete. Mag. Concr. Res. 2022, 74, 1165–1175. [Google Scholar]
  26. Bogas, J.A.; Ahmed, H.H.; Diniz, T. Influence of Cracking on the Durability of Reinforced Concrete with Carbon Nanotubes. Appl. Sci. 2021, 11, 1672. [Google Scholar] [CrossRef]
  27. Hassan, A.; Elkady, H.; Shaaban, I.G. Effect of Adding Carbon Nanotubes on Corrosion Rates and Steel-Concrete Bond. Sci. Rep. 2019, 9, 6285. [Google Scholar]
  28. Joshi, M.; Bavache, P.; Jamdar, M.; Bhanase, S.; Bhonge, S.; Chougule, S. Concrete Structure by Using Carbon Nanotube and Its Use to Monitor Its Structural Health. Int. J. Res. Appl. Sci. Eng. Technol. 2023, 11, 1995. [Google Scholar]
  29. Liu, Y.; Zhong, X.; Mohammadian, H.R. Role carbon nanomaterials in reinforcement of concrete and cement; A new perspective in civil nengineering. Alex. Eng. J. 2023, 72, 649–656. [Google Scholar]
  30. Pisello, A.L.; D’Alessandro, A.; Sambuco, S.; Rallini, M.; Ubertini, F.; Asdrubali, F.; Materazzi, A.L.; Cotana, F. Multipurpose experimental characterization of smart nanocomposite cement-based materials for thermal-energy efficiency and strain-sensing capability. Sol. Energy Mater. Sol. Cells 2017, 161, 77–88. [Google Scholar]
  31. Dinesh, A.; Ashwathi, R.; Kamal, B.; Akash, S.; Sujith, S. Influence of carbon nanotube on the mechanical and electrical characteristics of concrete—A review. Mater. Today Proc. 2023, 29, 999–1005. [Google Scholar] [CrossRef]
  32. Al-Rub, R.K.A.; Asce, M.; Tyson, B.M.; Asce, S.M.; Yazdanbakhsh, A.; Grasley, Z. Mechanical Properties of Nanocomposite Cement Incorporating Surface-Treated and Untreated Carbon Nanotubes and Carbon Nanofibers. J. Nanomechanics Micromech. 2011, 2, 1–6. [Google Scholar] [CrossRef]
  33. Yan, X.; Cui, H.; Qin, Q.; Tang, W.; Zhou, X. Study on Utilization of Carboxyl Group Decorated Carbon Nanotubes and Carbonation Reaction for Improving Strengths and Microstructures of Cement Paste. Nanomaterials 2016, 6, 153. [Google Scholar] [CrossRef] [PubMed]
  34. Li, S.; Zhang, Y.; Cheng, C.; Wei, H.; Du, S.; Yan, J. Surface-treated carbon nanotubes in cement composites: Dispersion, mechanical properties and microstructure. Constr. Build. Mater. 2021, 310, 125262. [Google Scholar] [CrossRef]
  35. Cui, K.; Liang, K.; Jiang, T.; Zhang, J.; Lau, D.; Chang, J. Understanding the role of carbon nanotubes in low-carbon concrete: From experiment to molecular dynamics. Cem. Concr. Compos. 2023, 142, 105189. [Google Scholar] [CrossRef]
  36. Zhao, L.; Nasution, M.K.N.; Hekmatifar, M.; Sabetvand, R.; Kamenskov, P.; Toghraie, D. The improvement of mechanical properties of conventional concretes using carbon nanoparticles using molecular dynamics simulation. Sci. Rep. 2021, 11, 20265. [Google Scholar] [CrossRef]
  37. Roopa, A.K.; Hunashyal, A.M.; Patil, A.Y.; Patil, A.; Soudagar, M.; Shahapurkar, K.; Khan, Y.; Kalam, M.A. Study on Interfacial Interaction of Cement-Based Nanocomposite by Molecular Dynamic Analysis and an RVE Approach. Adv. Civ. Eng. 2023, 2023, 8404335. [Google Scholar] [CrossRef]
  38. Qin, R.; Zhou, A.; Yu, Z.; Wang, Q.; Lau, D. Role of carbon nanotube in reinforcing cementitious materials: An experimental and coarse-grained molecular dynamics study. Cem. Concr. Res. 2021, 147, 106517. [Google Scholar] [CrossRef]
  39. Sindu, B.S.; Sasmal, S. Molecular dynamics simulations for evaluation of surfactant compatibility and mechanical characteristics of carbon nanotubes incorporated cementitious composite. Constr. Build. Mater. 2020, 253, 119190. [Google Scholar]
  40. Yu, Z.; La, D. Evaluation on mechanical enhancement and fire resistance of carbon nanotube (CNT) reinforced concrete. Coupled Syst. Mec. 2017, 6, 335. [Google Scholar]
  41. Merodio-Perea, R.G.; Páez-Pavón, A.; Lado-Touriño, I. Reinforcing cement with pristine and functionalized carbon nanotubes: Experimental and simulation studies. Int. J. Smart Nano Mater. 2020, 11, 370–386. [Google Scholar] [CrossRef]
  42. Biovia Materials Studio, an Integrated, Multi-Scale Modelling Environment. Available online: https://www.3ds.com/productsservices/biovia/products/molecular-modeling-simulation/biovia-materials-studio (accessed on 14 January 2025).
  43. Hoover, W.G. Canonical dynamics: Equilibrium phase-space distributions. Phys. Rev. A 1985, 31, 1695–1697. [Google Scholar] [CrossRef] [PubMed]
  44. Nosé, S. A molecular dynamics method for simulations in the canonical ensemble. Mol. Phys. 1984, 52, 255–268. [Google Scholar] [CrossRef]
  45. Sun, H.; Ren, P.; Fried, J.R. The COMPASS force field: Parameterization and validation for phosphazenes. Comput. Theor. Polym. Sci. 1998, 8, 229–246. [Google Scholar] [CrossRef]
  46. Bhuvaneshwari, B.; Palani, G.S.; Karunya, R.; Iyer, N.R. Nano mechanical properties on the mineralogical array of calcium silicate hydrates and calcium hydroxide through molecular dynamics. Curr. Sci. 2015, 108, 1058–1065. [Google Scholar]
  47. Li, K.; Shui, Z.H.; Dai, W. Molecular dynamic simulation of structural and mechanical properties of cement hydrates: From natural minerals to amorphous phases. Mater. Res. Innov. 2011, 16, 338–344. [Google Scholar] [CrossRef]
  48. Hajilar, S.; Shafei, B. Nano-scale investigation of elastic properties of hydrated cement paste constituents using molecular dynamics simulations. Comput. Mater. Sci. 2015, 101, 216–226. [Google Scholar] [CrossRef]
  49. Afsharhashemkhani, S.; Jamal-Omidi, M.; Tavakolian, M. A molecular dynamics study on the mechanical properties of defective CNT/epoxy nanocomposites using static and dynamic deformation approaches. Int. Polym. Process. 2022, 37, 176–190. [Google Scholar] [CrossRef]
  50. Arar, A. Elastic Properties of Cement Phases Using Molecular Dynamic Simulation. Ph.D. Thesis, Toronto Metropolitan University, Toronto, Canada, 2016. [Google Scholar]
  51. Hajilar, S.; Shafei, B. Molecular Dynamics Simulation of Elastic Properties of Ordered CSH Gel: Case Study of Tobermorite and Jennite. In Proceedings of the 5th International Symposium of Nanotechnology in Construction (NICOM-5), Chicago, IL, USA, 24–26 May 2015. [Google Scholar]
  52. Hajilar, S.; Shafei, B. Molecular dynamics simulation of elastic properties of tobermorite family. In Proceedings of the 4th RILEM International Symposium on Concrete Modeling (CONMOD 2014), Beijing, China, 12–14 October 2014. [Google Scholar]
  53. Cho, B.H.; Chung, W.; Nam, B.H. Molecular Dynamics Simulation of Calcium-Silicate-Hydrate for Nano-Engineered Cement Composites—A Review. Nanomaterials 2020, 10, 2158. [Google Scholar] [CrossRef]
  54. Chung, D.H.; Buessem, W.R. The Voigt-Reuss-Hill Approximation and Elastic Moduli of Polycrystalline MgO, CaF2, ZnS, ZnSe, and CdTe. J. Appl. Phys. 2004, 38, 2535. [Google Scholar]
  55. Eftekhari, M.; Mohammadi, S. Molecular Dynamics Simulation of the Nonlinear Behavior of the CNT-Reinforced Calcium Silicate Hydrate (C-S-H) Composite. Compos. A Appl. Sci. Manuf. 2016, 82, 78–87. [Google Scholar]
  56. Musso, S.; Tulliani, J.M.; Ferro, G.; Tagliaferro, A. Influence of carbon nanotubes structure on the mechanical behavior of cement composites. Compos. Sci. Technol. 2009, 69, 1985–1990. [Google Scholar]
  57. Wang, J.F.; Zhang, L.W.; Liew, K.M. Multiscale simulation of mechanical properties and microstructure of CNT-reinforced cement-based composites. Comput. Methods Appl. Mech. Eng. 2017, 319, 393–413. [Google Scholar]
  58. Ramezani, M.; Dehghani, A.; Sherif, M.M. Carbon nanotube reinforced cementitious composites: A comprehensive review. Constr. Build. Mater. 2022, 315, 125100. [Google Scholar]
  59. Velez, K.; Maximilien, S.; Damidot, D.; Fantozzi, G.; Sorrentino, F. Determination by nanoindentation of elastic modulus and hardness of pure constituents of Portland cement clinker. Cem. Concr. Res. 2001, 31, 555–561. [Google Scholar]
  60. Jennings, H.M. A model for the microstructure of calcium silicate hydrate in cement paste. Cem. Concr. Res. 2000, 30, 110–116. [Google Scholar]
  61. Yoshimura, H.N.; Molisani, A.L.; Narita, N.E.; Cesar, P.F.; Goldenstein, H. Porosity dependence of elastic constants in aluminum nitride ceramics. Mater. Res. 2007, 10, 127–133. [Google Scholar]
  62. Fu, J.; Bernard, S.; Kamali-Bernard, S. Assessment of the elastic properties of amorphous calcium silicates hydrates (I) and (II) structures by molecular dynamics simulation. Mol. Simul. 2018, 44, 285–299. [Google Scholar]
  63. González-Teresa, R.; Morales-Florez, V.; Manzano, H.; Dolado, J.S. Modelos estructurales del empaquetamiento aleatorio de partículas esféricas de Tobermorita: Una aproximación computacional sencilla. Mater. Constr. 2010, 60, 7–15. [Google Scholar]
  64. Constantinides, G.; Ulm, F.J. The effect of two types of C-S-H on the elasticity of cement-based materials: Results from nanoindentation and micromechanical modeling. Cem. Concr. Res. 2004, 34, 67–80. [Google Scholar]
  65. Keinde, D. Etude du Béton à l’échelle Mesoscopique: Simulation Numérique et Tests de Micro-Indentation. Ph.D. Thesis, Institut National des Sciences Appliquées de Rennes, Rennes, France, 2014. [Google Scholar]
  66. Sánchez, F.; Zhang, L. Molecular dynamics modeling of the interface between surface functionalized graphitic structures and calcium–silicate–hydrate: Interaction energies, structure, and dynamics. J. Colloid. Interface Sci. 2008, 323, 349–358. [Google Scholar] [CrossRef] [PubMed]
  67. Yilmaz, Y.I. Analyzing Single Fiber Fragmentation Test Data by Using Stress Transfer Model. J. Compos. Mater. 2002, 36, 537–551. [Google Scholar]
  68. Al-Muhit, B.; Sanchez, F. Nano-engineering of the mechanical properties of tobermorite 14 Å with graphene via molecular dynamics simulations. Constr. Build. Mater. 2020, 233, 117237. [Google Scholar] [CrossRef]
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Figure 1. Tobermorite matrix containing 3 CNTs (a) and 12 CNTs (b). Cell dimensions: A = 20.205 Å, B = 36.920 Å, and C = 44.974 Å. Carbon is represented in gray, hydrogen in white, oxygen in red, silicon in orange, and calcium in green.
Figure 1. Tobermorite matrix containing 3 CNTs (a) and 12 CNTs (b). Cell dimensions: A = 20.205 Å, B = 36.920 Å, and C = 44.974 Å. Carbon is represented in gray, hydrogen in white, oxygen in red, silicon in orange, and calcium in green.
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Figure 2. (a) Pristine CNT, (b) CNT functionalized with two carboxyl groups, and (c) CNT functionalized with four carboxyl groups. Carbon is represented in gray, hydrogen in white, and oxygen in red.
Figure 2. (a) Pristine CNT, (b) CNT functionalized with two carboxyl groups, and (c) CNT functionalized with four carboxyl groups. Carbon is represented in gray, hydrogen in white, and oxygen in red.
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Figure 3. Young’s modulus values obtained for each structure.
Figure 3. Young’s modulus values obtained for each structure.
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Figure 4. Close-up view of the hydrogen bonds (black dashed lines) formed between tobermorite and a CNT functionalized with four carboxyl groups. Carbon is represented in gray, hydrogen in white, silicon in orange and oxygen in red.
Figure 4. Close-up view of the hydrogen bonds (black dashed lines) formed between tobermorite and a CNT functionalized with four carboxyl groups. Carbon is represented in gray, hydrogen in white, silicon in orange and oxygen in red.
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Table 1. Composition of studied structures (in the nomenclature shown in parentheses, “PT” indicates pristine CNTs (non-functionalized), the first number represents the number of carboxyl groups used to functionalize the CNTs, and the last number denotes the number of CNTs in the structure).
Table 1. Composition of studied structures (in the nomenclature shown in parentheses, “PT” indicates pristine CNTs (non-functionalized), the first number represents the number of carboxyl groups used to functionalize the CNTs, and the last number denotes the number of CNTs in the structure).
StructureNo. of CNTs
Tobermorite + CNT (PTCNT3)3 (2.5)
Tobermorite + CNT (PTCNT7)7 (2.6)
Tobermorite + CNT (PTCNT12)12 (2.7)
Tobermorite + CNT + 2COOH (CNT2C2)2 (2.5)
Tobermorite + CNT + 2COOH (CNT2C6)6 (2.6)
Tobermorite + CNT + 2COOH (CNT2C10)10 (2.7)
Tobermorite + CNT + 4COOH (CNT4C3)3 (2.5)
Tobermorite + CNT + 4COOH (CNT4C7)7 (2.6)
Tobermorite + CNT + 4COOH (CNT4C12)12 (2.7)
Table 2. Computed mechanical properties.
Table 2. Computed mechanical properties.
StructureK (GPa)G (GPa)E (GPa)ν
Tobermorite43.9931.9877.050.21
PTCNT345.4332.4678.120.21
PTCNT746.9333.1780.200.21
PTCNT1265.5632.5381.930.27
CNT2C289.9432.4182.180.27
CNT2C652.0534.5484.600.22
CNT2C1068.6934.2387.640.28
CNT4C354.2233.4891.910.24
CNT4C780.0637.3596.550.29
CNT4C1257.5040.9097.870.20
Table 3. Values of E calculated using Equation (3) as a function of the average porosity for HD (0.26) and LD (0.36) structures.
Table 3. Values of E calculated using Equation (3) as a function of the average porosity for HD (0.26) and LD (0.36) structures.
StructureEo (GPa)E (Gpa)
p = 0.26		E (Gpa)
p = 0.36
Tobermorite77.0531.8322.66
PTCNT378.1232.2722.97
PTCNT780.2033.1323.58
PTCNT1281.9333.8524.09
CNT2C282.1833.9524.16
CNT2C684.6034.9524.88
CNT2C1087.6436.2025.77
CNT4C391.9137.9727.03
CNT4C796.5539.8928.39
CNT4C1297.8740.4328.78
Table 4. Average number of H-bonds (NHB) and length (dHB) between CNTs and the tobermorite surface.
Table 4. Average number of H-bonds (NHB) and length (dHB) between CNTs and the tobermorite surface.
StructureNHBdHB (Å)
CNT2C210.001.85
CNT2C637.001.92
CNT2C1049.001.95
CNT4C325.001.89
CNT4C752.671.97
CNT4C1286.001.93
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Merodio-Perea, R.G.; Terrón-López, M.-J.; Lado-Touriño, I. Molecular Dynamics Simulation of CNT Reinforced Cement: A Step Toward Sustainable Construction. Sustainability 2025, 17, 3185. https://doi.org/10.3390/su17073185

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Merodio-Perea RG, Terrón-López M-J, Lado-Touriño I. Molecular Dynamics Simulation of CNT Reinforced Cement: A Step Toward Sustainable Construction. Sustainability. 2025; 17(7):3185. https://doi.org/10.3390/su17073185

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Merodio-Perea, Rosario G., María-José Terrón-López, and Isabel Lado-Touriño. 2025. "Molecular Dynamics Simulation of CNT Reinforced Cement: A Step Toward Sustainable Construction" Sustainability 17, no. 7: 3185. https://doi.org/10.3390/su17073185

APA Style

Merodio-Perea, R. G., Terrón-López, M.-J., & Lado-Touriño, I. (2025). Molecular Dynamics Simulation of CNT Reinforced Cement: A Step Toward Sustainable Construction. Sustainability, 17(7), 3185. https://doi.org/10.3390/su17073185

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