A potential C-S-H nucleation mechanism: atomistic simulations of the portlandite to C-S-H transformation

Aretxabaleta, X. M.; López-Zorrilla, Jon; Labbez, Christophe; Etxebarria, I.; Manzano, Hegoi

doi:10.1016/j.cemconres.2022.106965

Cited by 20 publications

(12 citation statements)

References 79 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The exploration of stone powder in research should extensively delve into smaller scales. Recently, methods based on atomistic simulations have provided a deeper understanding of the cement hydration process. , Research on the impact of stone powder can similarly penetrate this level, thereby achieving a profound understanding of its underlying mechanisms on hydration process.…”

Section: Discussionmentioning

confidence: 99%

Sustainable Reusing Marble Powder and Granite Powder in Cement-Based Materials: A Review

Hou,

Zhang,

Zhuang

et al. 2024

ACS Sustainable Chem. Eng.

View full text Add to dashboard Cite

Marble powder (MP) and granite powder (GP) are disposed of primarily through landfilling, which leads to severe environmental issues. The utilization of stone powder in cement-based materials offers a scalable disposal method. This paper begins by presenting the two powders’ basic physicochemical and micromorphological characteristics. Then the effects and mechanisms of MP and GP on the hydration process and microstructure of the concrete are examined. Moreover, the influences of different substitution methods, water-cement ratio, and other factors on the macro properties of concrete incorporating stone powder are comprehensively summarized, bridging the gap between the microscopic changes induced by the addition of stone powder and the macroscopic differences observed in experiments. The current state of relevant technical standards is analyzed. Leveraging previous research results, we used machine learning techniques to optimize the mixture ratio of stone powder concrete with the aim of achieving a comprehensive life cycle performance index. The results reveal that by fully exploiting the fineness and composition characteristics of MP and GP, along with employing a suitable mix design, stone powders exhibit filling and nucleation effects that accelerate cement hydration, refine the pore structure, and enhance the workability, mechanical properties, and durability of concrete. Following the proposed optimization of the concrete mixture ratio, substituting 16% of cement can maintain the standard strength of 50 MPa while reducing the carbon footprint by 108.8 kg CO2e/m3 as well as saving the cost of 284.8 yuan/m3. This Review is expected to promote further applications of waste stone powder in cement-based materials to achieve sustainable development.

show abstract

Section: Discussionmentioning

confidence: 99%

Sustainable Reusing Marble Powder and Granite Powder in Cement-Based Materials: A Review

Hou,

Zhang,

Zhuang

et al. 2024

ACS Sustainable Chem. Eng.

View full text Add to dashboard Cite

show abstract

“…With the recent developments and widespread use of enhanced sampling techniques coupled with DFT and MD, the future of molecular simulations in the field of cementitious materials is promising [104,118,119]. These techniques enable wider exploration of the system essentially overcoming the limitations of time and energy barrier constraints in the normal MD or DFT simulations.…”

Section: Discussionmentioning

confidence: 99%

“…The authors highlighted the limitations of this study in terms of only looking at monomeric species, however, this was first of its kind and the first step towards understanding the formation pathway of C-A-S-H (FigureB). Recently, Aretxabaleta et al used a combination of several different techniques to assess a possible C-S-H nucleation pathway from a monolayer of portlandite[118]. The authors concluded that although such a mechanism is possible, one must consider the formation of calcium silicate complexes which could prevent the formation of the portlandite monolayer in the first place.…”

mentioning

confidence: 99%

Molecular modelling of cementitious materials: current progress and benefits

et al. 2023

View full text Add to dashboard Cite

Developing new sustainable concrete technology has become an urgent need, requiring faster and deeper insights into the fundamental mechanisms driving the cement hydration reactions. Molecular simulations have the potential to provide such understanding since the hydration reaction and the cement chemistry are particularly dominated by mechanisms at the atomic scale. In this letter, we review the application of two major approaches namely classical (including reactive) molecular dynamics simulations and density function theory calculations of cementitious materials. We give an overview of molecular simulations involving the major mineral and hydrate phases.

show abstract

“…That is the coordination of Ca atoms in the C-S-H gel intralayer region 25,26 , and it is common to use such a structural feature to characterize the early formation of C-S-H from Synchrotron X-ray powder diffraction (SXRPD) 50,51 . Our simulations indicate that the complexes may already display such coordination, and therefore they may interfere with the characterization of the solid phase.…”

Section: Computational Detailsmentioning

confidence: 99%

C-S-H nucleation pathway from atomistic simulations

Aretxabaleta

López-Zorrilla

Etxebarria

et al. 2023

Preprint

View full text Add to dashboard Cite

C-S-H nucleation is a crucial step during cement hydration and determines to a great extent the rheology, microstructure, and properties of the cement paste. Recent evidences indicate that the C-S-H nucleation is non-classical, yet detailed information on the nucleation steps is still missing. In this work, we use atomistic simulation methods, specifically DFT, evolutionary algorithms (EA), and Molecular Dynamics, to investigate the structure and formation of C-S-H prenucleation clusters (PNCs) from the ions in solution, and then discuss a possible formation pathway for the C-S-H nucleation. Our simulations indicate that even for small sizes the most stable clusters feature C-S-H structural motifs, and we identified a C4S4H2 cluster candidate to be the C-S-H basic building block. We suggest a formation path in which small clusters formed by silicate dimers merge into large elongated aggregates. Upon dehydration, the C-S-H basic building blocks can be formed within the aggregates, and eventually crystallize.

show abstract

A potential C-S-H nucleation mechanism: atomistic simulations of the portlandite to C-S-H transformation

Cited by 20 publications

References 79 publications

Sustainable Reusing Marble Powder and Granite Powder in Cement-Based Materials: A Review

Sustainable Reusing Marble Powder and Granite Powder in Cement-Based Materials: A Review

Molecular modelling of cementitious materials: current progress and benefits

C-S-H nucleation pathway from atomistic simulations

Contact Info

Product

Resources

About