Article
Construction & Building Technology
Jiawei Wang, Zhangli Hu, Yang Chen, Jiale Huang, Yuefeng Ma, Weiwei Zhu
Summary: This study investigated the effect of porosity and chemical composition of C(-A)-S-H on its micromechanical properties using nanoindentation. The results showed that porosity and Ca/Si ratio significantly influenced the mechanical properties of C(-A)-S-H, while the addition of aluminum slightly altered its creep modulus.
CEMENT AND CONCRETE RESEARCH
(2022)
Article
Construction & Building Technology
Zhiyu Luo, Wengui Li, Yixiang Gan, Xuzhen He, Arnaud Castel, Daichao Sheng
Summary: The addition of nano-SiO2 and nano-TiO2 particles in fly ash-based geopolymers improved compressive strength and micro mechanical properties of N-A-S-H gels. Nano-SiO2 had a greater impact on macro-strength, while nano-TiO2 significantly enhanced gel micro-mechanical properties. Both nanoparticles showed a positive effect on the early reaction rate of geopolymers.
CEMENT & CONCRETE COMPOSITES
(2021)
Article
Construction & Building Technology
Rotana Hay, Jiaqi Li, Kemal Celik
Summary: The study found that Portland cement forms a large amount of highly polymerized silica gels during carbonation, achieving a high carbonation content. CaCO3 polymorphs dominate, and the carbonated material exhibits improved micromechanical properties.
CEMENT AND CONCRETE RESEARCH
(2022)
Article
Construction & Building Technology
Van Phi Dang, Dong Joo Kim
Summary: Single-fiber pullout tests were conducted on smooth-steel fibers embedded in ultra-high-performance concrete (UHPC) containing nanoparticles (NPs) at various pullout speeds. The addition of NPs to UHPC significantly increased the rate sensitivity of fiber pullout resistance. Among the NPs, the addition of 3 wt% nano-CaCO3 resulted in the highest rate sensitivities for req (DIF = 1.95) and rpeak (DIF = 2.06).
CEMENT & CONCRETE COMPOSITES
(2023)
Article
Construction & Building Technology
Daniel Wagner, Frank Bellmann, Juergen Neubauer
Summary: The study found that adding potassium hydroxide (KOH) solutions of different concentrations accelerates the hydration process of C3S, leading to an increase in the interfacial precipitation rate of C-S-H. By using isothermal calorimetry and ICP-OES measurements, it was determined that KOH solutions have an enhancing effect on the early hydration reaction rates of C3S.
CEMENT AND CONCRETE RESEARCH
(2021)
Article
Chemistry, Multidisciplinary
Hang Yin, Xuefeng Wang, Haifeng Qin, Shijie Wang, Kun Cai
Summary: This study simulated the nanoindentation on the C-S-H gel samples by the molecular dynamics method and revealed that C-S-H gels exhibit bi-modulus and transverse isotropy. The modulus in a direction increased with the loading speed, indicating the viscous behavior of C-S-H due to water motion and stress wave propagation. The saturation of water affected the moduli differently.
Article
Construction & Building Technology
Aniruddha Baral, Elena Tajuelo Rodriguez, William A. Hunnicutt, Ercan Cakmak, Hongbin Sun, Jan Ilavsky, Yann Le Pape, Thomas M. Rosseel, Nishant Garg
Summary: Research findings show that high-dose irradiation leads to stiffening and structural changes in the concrete biological shield of nuclear power plants, which has significant implications for their long-term operation worldwide.
CEMENT AND CONCRETE RESEARCH
(2022)
Article
Construction & Building Technology
Aarti Solanki, L. P. Singh, S. R. Karade, U. Sharma
Summary: The study found that silica nanoparticles (SNPs) promote the hydration of tricalcium aluminate (C3A) at the early stage of hydration, but subsequently lead to a retardation in the reaction. This retardation may be attributed to the surface coverage of C3A grains by calcium silicate hydrate (C-S-H) and calcium alumina silicate hydrate (C-A-S-H).
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Materials Science, Ceramics
Wensheng Zhang, Jiangtao Zhang, Jiayuan Ye, Xuehong Ren, Lei Liu, Weiguo Shen
Summary: The study shows that NaAlO2 significantly enhances the hydration kinetics of Al-doped beta-C2S, increases early-age mechanical strength, promotes the incorporation of Al in the C-(A)-S-H structure, and accelerates the formation of C-(A)-S-H phases containing tetra-, penta- and hexa-coordinated Al.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2022)
Article
Construction & Building Technology
Sumin Im, Hyeonseok Jee, Heongwon Suh, Manabu Kanematsu, Satoshi Morooka, Hongbok Choe, Nishio Yuhei, Akihiko Machida, Jihoon Kim, Seungmin Lim, Sungchul Bae
Summary: In this study, the mechanical properties and deformation behavior of synthetic C-S-H pastes with different Ca/Si ratios under external loading were investigated. It was found that the presence of multiscale pores in the pastes allowed the stress to be transferred from the surface to the particles, resulting in different deformation behavior.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Construction & Building Technology
Gyeongryul Kim, Sumin Im, Hyeonseok Jee, Heongwon Suh, Seongmin Cho, Manabu Kanematsu, Satoshi Morooka, Taku Koyama, Yuhei Nishio, Akihiko Machida, Jihoon Kim, Sungchul Bae
Summary: This study explored the effect of M-S-H formation on the local atomic arrangements and mechanical properties of C-S-H. It was found that at high Mg/Si ratios, the low pH environment facilitated the formation of M-S-H, leading to a change in the dominant phase from C-S-H to M-S-H and an increase in the elastic modulus of the samples.
CEMENT AND CONCRETE RESEARCH
(2022)
Article
Chemistry, Multidisciplinary
Marcel Maslyk, Tobias Gaeb, Galina Matveeva, Phil Opitz, Mihail Mondeshki, Yasar Krysiak, Ute Kolb, Wolfgang Tremel
Summary: The study demonstrates that CO2 emissions during clinker production of cement can be reduced by utilizing a metathesis reaction at room temperature in ball-mills. This method involves forming aNaSiCC, an amorphous intermediate, by mechanochemical activation of CaCO3 and Na2SiO3. It helps understand the interplay between thermodynamics and kinetics in complex reactions of alkali-activated binders and for CaCO3 crystallization in industrial and geochemical settings.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Physical
Dongbo Li, Jing Zhu, Qinlong Liu, Qinde Qi, Zhentao Bai
Summary: Water molecules confined in nanopores at elevated temperatures can interfere with the structure of C-S-H, causing pore expansion and increasing the diffusion coefficient of confined water. High temperatures can also promote hydrolysis reactions and the breakage of chemical bonds, leading to a decrease in the mechanical properties of C-S-H. Additionally, uniaxial tensile tests at high temperatures show thermal curling of the silicate chains in the C-S-H substrate.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Mohammad Rafat Sadat, Krishna Muralidharan, George N. Frantziskonis, Lianyang Zhang
Summary: A multiscale approach combining molecular dynamics (MD) and peridynamics (PD) simulations was used to investigate the mechanical behavior of geopolymer composites (GC). The MD determined intrinsic mechanical properties which were then input into PD simulations. It was found that the strength of GC increases with increasing domain sizes of the constituent phases.
COMPUTATIONAL MATERIALS SCIENCE
(2021)
Article
Chemistry, Physical
Lingmin Sun, Junshu Wu, Jinshu Wang, Yunfei Yang, Wenyuan Zhou, Yilong Yang, Yucheng Du, Peng Hu, Yongli Li, Hongyi Li
Summary: The translation discusses the reutilization of spent adsorbents to economically and realistically recover metals and rare earth elements, forming functional nanocomposites. The method involves successfully retaining metal ions and recovering noble metals through decalcification reactions, ultimately leading to the formation of SiO2-based heterostructures containing nanocrystalline metals or rare-earth oxides.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2022)
Article
Construction & Building Technology
Rotana Hay, Jiaqi Li, Kemal Celik
Summary: The study found that Portland cement forms a large amount of highly polymerized silica gels during carbonation, achieving a high carbonation content. CaCO3 polymorphs dominate, and the carbonated material exhibits improved micromechanical properties.
CEMENT AND CONCRETE RESEARCH
(2022)
Article
Construction & Building Technology
Inderjeet Singh, Rotana Hay, Kemal Celik
Summary: The study investigated the direct carbonation of brucite recovered from reject brine and observed significant improvement in mechanical properties post-carbonation. Findings suggest that cost-effective synthesis of brucite from reject brine could sequester CO2, making it a promising material for the construction industry.
CEMENT AND CONCRETE RESEARCH
(2022)
Article
Construction & Building Technology
Rotana Hay, Liang Li, Kemal Celik
Summary: This study investigated the effect of different levels of hemihydrate sulfation on the autogenous shrinkage of limestone calcined clay cement (LC3) based mixes. The results showed that optimal mechanical performance could be achieved at a specific sulfation level. The study also revealed the coupling effect of physicochemical and microstructural changes on autogenous shrinkage and the performance of LC3-based concrete composites.
CEMENT & CONCRETE COMPOSITES
(2022)
Article
Construction & Building Technology
Jiaqi Li, Qi Zheng
Summary: This study investigates the effect of GO and PCE on the nanomechanical properties of C-S-H and finds that PCE-induced GO nanoplatelets can strengthen the basal planes of C-S-H, enhancing the macroscopic properties of the material, but have little impact on the c-axis of C-S-H.
CEMENT AND CONCRETE RESEARCH
(2022)
Article
Engineering, Environmental
Jiaqi Li, Qingxu Jin, Wenxin Zhang, Chen Li, Paulo J. M. Monteiro
Summary: This paper explores the potential of using biosilica as a byproduct from diatom-based biofuel production in cementitious materials. The study finds that replacing some portland cement with biosilica can improve the durability performance of the materials, although it may increase drying shrinkage. The research also demonstrates the feasibility of using biosilica as a sustainable cement substitute.
RESOURCES CONSERVATION AND RECYCLING
(2022)
Article
Materials Science, Multidisciplinary
David W. Gardner, Jiaqi Li, Martin Kunz, Wei-Chih Liao, Chenhui Zhu, Carlo Carraro, Paulo J. M. Monteiro, Roya Maboudian
Summary: This article investigates the intergrain and intragrain interactions of calciumsilicate-hydrates (C-S-H), nanocrystalline forms of tobermorites, which control the long-term stress response of concrete. Through experiments, it is found that layer stacking disorder significantly increases in 11 angstrom tobermorite powder. Similar results are observed in nanocrystalline C-S-H powders, where layer stacking disorder (in the form of intragrain deformation) increases with low water content and large basal spacing.
Article
Construction & Building Technology
Rotana Hay, Bo Peng, Kemal Celik
Summary: This study explored the impact of different CaCO3 polymorphs from limestone and seashell on the hydration and carbonation kinetics of reactive MgO cement (RMC). The results showed that the limestone powder had superior filler effects, enhancing the early stage of hydration and increasing the compressive strength under air curing. The nucleation effect of limestone did not promote more brucite formation but involved the creation of amorphous phases, which encapsulated and passivated the MgO substrate, thereby restricting its hydration. Under carbonation, nucleation induced by both CaCO3 forms improved the composite strengths by producing carbonation products of larger morphologies, resulting in pore filling and matrix densification. Amorphous phases with hydromagnesite-like and fused structures were observed.
CEMENT AND CONCRETE RESEARCH
(2023)
Article
Engineering, Multidisciplinary
Jiaqi Li, Wenxin Zhang
Summary: The study reveals the texture formation of C-S-H under pressure and the time-dependence of the preferred orientation development. These findings are crucial for understanding the mechanical performance of concrete.
COMPOSITES PART B-ENGINEERING
(2022)
Article
Construction & Building Technology
Rotana Hay, Abdullah Khalil, Cornelius Otchere, Sara Alanis, Kemal Celik
Summary: This study assessed the influence of PCE-based superplasticizers on the hydration and carbonation kinetics of reactive magnesium oxide (MgO) cement. Highly workable RMC-based composites were achieved with the addition of superplasticizers and fibers, and a higher compressive strength was obtained under carbonation conditions. The PE fibers provided crack control mechanism, and the finalized mix was successfully applied for the construction of a large-scale architectural structure.
JOURNAL OF MATERIALS IN CIVIL ENGINEERING
(2023)
Article
Construction & Building Technology
Xiaohong Zhu, Yuying Zhang, Liang Chen, Lei Wang, Bin Ma, Jiaqi Li, Chi Sun Poon, Daniel C. W. Tsang
Summary: This study investigated the interfacial transition zone (ITZ) in biochar-augmented carbon-negative cementitious materials using various analysis techniques. The results revealed significant changes in hydration degree and porosity at the edge of biochar. The integration of biochar and cement was mainly achieved through the formation of Ca-rich hydration products. In terms of mechanical behavior, biochar exhibited viscous-elastic deformation while hardened cement displayed plastic-elastic properties. The distinct differences in deformation contributed to the higher compressive strength of biochar-cement composites.
CEMENT & CONCRETE COMPOSITES
(2023)
Review
Construction & Building Technology
Chen Li, Jiaqi Li, Qiaomu Zheng, Qiang Ren, Zhengwu Jiang
Summary: Extending the service life of structures is crucial for mitigating environmental impacts, such as global warming. While the durability of reinforced concrete has been studied for decades, its impact on eco-efficiency has only recently gained attention. This review discusses the recent advances in durability-based life cycle assessment (LCA) and highlights the need for a unified methodology in this field. It proposes a framework that combines prescriptive and performance-based design methods to unify existing divergent methodologies and improve sustainability in engineering codes.
CEMENT & CONCRETE COMPOSITES
(2023)
Article
Construction & Building Technology
Ke Xu, Qingxu Jin, Jiaqi Li, Daniela M. Ushizima, Victor C. Li, Kimberly E. Kurtis, Paulo J. M. Monteiro
Summary: The application of machine learning and computer vision in microtomography allows for the analysis of microstructural evolutions in strain-hardening cementitious composites (SHCC) under tensile load. This study developed a machine learning pipeline combined with digital volume correlation for automated microtomography segmentation analysis (MSA) to separate different components and quantify the 3D morphological properties of fibers and pore networks in SHCC. The research revealed that strain localization and crack initiation occurred around interconnected pores, rather than at the weakest cross-section defined by the fiber distribution and porosity. The study also found that fibers reinforced crack planes through various mechanisms, contributing to crack width control and ductility of SHCC. This work is important for understanding the progressive damage mechanisms of SHCC and refining the characterization, modeling, and design of the composite material.
CEMENT AND CONCRETE RESEARCH
(2023)
Article
Construction & Building Technology
Qi Zheng, Chengyao Liang, Jinyang Jiang, Haiyan Mao, Karen C. Bustillo, Chengyu Song, Jeffrey A. Reimer, Paulo J. M. Monteiro, Haimei Zheng, Shaofan Li
Summary: This study used scanning transmission electron microscopy to examine defects in cement particles at the single-atom level. The researchers identified different types of defects and found that they play a crucial role in cement hydration, facilitating dissolution and providing nucleation sites for hydration products.
CEMENT AND CONCRETE RESEARCH
(2024)
Article
Construction & Building Technology
Anuj Parashar, Shashank Bishnoi
Summary: This study investigated the hydration of siliceous fly ash, slag, and metakaolin with calcium hydroxide, and found that the rate of hydration and phase assemblage is influenced by the alkali and sulphate content, while siliceous fly ash is less affected by alkalis and sulphates.
CEMENT AND CONCRETE RESEARCH
(2024)
Article
Construction & Building Technology
Peimin Zhan, Juan Wang, Hanbing Zhao, Wengui Li, Surendra P. Shah, Jing Xu
Summary: This study investigates the influence of hydrothermal synthetic conditions on the properties of C-S-H seeds and reveals the correlations between C-S-H seeds properties, hydration kinetics, and paste performances. It is found that low reactant concentrations and calcium-to-silicon ratios facilitate the production of C-S-H seeds with small size and high purity. Using C-S-H seeds with high effective surface area accelerates the hydration process of cement, resulting in refined pore structure and enhanced strength.
CEMENT AND CONCRETE RESEARCH
(2024)
Article
Construction & Building Technology
Zhaozheng Meng, Qing-feng Liu, Neven Ukrainczyk, Song Mu, Yufei Zhang, Geert De Schutter
Summary: This study developed a numerical framework to investigate the combined attack of sulfate and chloride ions on cementitious materials in marine and saline environments. The study quantified various chemical reactions and solved the electrostatic potential caused by multi-ion coupling. The results showed that neglecting the multi-ions coupling effect could result in an underestimated chemical coupling strength in competitive chloride-sulfate binding.
CEMENT AND CONCRETE RESEARCH
(2024)
Article
Construction & Building Technology
Ning Li, Cise Unluer
Summary: This study aimed to improve the carbonation efficiency and reduce processing time of recycled concrete aggregates (RCAs). Wet carbonation with seawater was found to be more efficient than dry carbonation, leading to significant reduction in water absorption and increase in density of RCAs. The compressive strength of recycled aggregate concrete (RAC) prepared with 1-hour seawater carbonated RCAs was also improved. The formation of ettringite and calcite under wet carbonation contributed to the increased density and strength, as well as improved bond strength in the interfacial transition zone of RAC. Seawater presents several advantages as a medium for wet carbonation, including its abundant availability, CO2 capture capacity, and accelerated hydration and carbonation.
CEMENT AND CONCRETE RESEARCH
(2024)
Article
Construction & Building Technology
Yong Tao, Yining Gao, Yanjie Sun, Roland J. -M. Pellenq, Chi Sun Poon
Summary: Decalcification of calcium silicate hydrates (C-S-H) is an important issue for the long-term safety of cement-based infrastructures. Using molecular simulations, this study reveals an important mechanism of accelerated C-S-H decalcification in seawater, which involves ion exchange between surface Ca and electrical double layers, resulting in a decrease in Ca dissolution free energy. This finding enhances the understanding and prediction of cementitious materials' degradation.
CEMENT AND CONCRETE RESEARCH
(2024)
Article
Construction & Building Technology
Kumaran Coopamootoo, Enrico Masoero
Summary: This study uses kinetic simulations to investigate the relationship between dissolution rate and saturation index in minerals in solution. Two distinct regimes are observed, with stresses at crystallographic defects controlling the transition between them. A parameterization of the interaction potentials is proposed to obtain consistent interfacial energies with water. The findings contribute to the current discussion on controlling reactivity using materials and defects.
CEMENT AND CONCRETE RESEARCH
(2024)
Article
Construction & Building Technology
Faping Li, Qianshi Chen, Yiyan Lu, Yunlong Zou, Shan Li
Summary: In this study, the impact of functionalized multi-walled carbon nanotubes and a silane coupling agent on the performance and microstructure of alkali-activated fly ash/slag pastes was investigated. The results showed that the addition of these materials can prolong setting time, improve flowability and mechanical strength, and reduce mass loss and drying shrinkage.
CEMENT AND CONCRETE RESEARCH
(2024)
Article
Construction & Building Technology
Yaozeng Wang, Wencui Yang, Ai Zhang, Penghuan Liu, Yong Ge
Summary: Low-temperature low-field nuclear magnetic resonance was used to analyze icing in water saturated white cement paste specimens during the freeze-thaw process at different temperatures. The experimental results were compared with classical theory, showing agreement at certain temperatures but discrepancies at others. New equations were proposed based on the analysis of specimens saturated with different solutions to relate the volume of frozen water to temperature during freezing and thawing of cementitious materials.
CEMENT AND CONCRETE RESEARCH
(2024)
Article
Construction & Building Technology
Shengjie Yan, Yingjie Liang
Summary: This paper proposes a fractal derivative model with a non-linear distributed-order (DOFM) to describe the multi-scaling behaviors of particle diffusion in alkali-activated materials. The DOFM is tested using experimental data and is found to effectively describe the multi-scaling diffusion behaviors of particles in the materials.
CEMENT AND CONCRETE RESEARCH
(2024)
Article
Construction & Building Technology
Cecilia Pesce, Richard J. Ball, Marco Molinari, Shaun Reeksting, Giovanni Luca Pesce
Summary: This study evaluates the effect of ten organic additives on the microstructure of portlandite crystals during CaO hydration. It was found that the presence of carbohydrates and sulfonates can alter the structure of portlandite and the properties of lime can be controlled by adding carbohydrates. This has significant implications for the development of new binders and reducing CO2 emissions.
CEMENT AND CONCRETE RESEARCH
(2024)
Article
Construction & Building Technology
Daniel Jansen, Alexander German, Dominique Ectors, Frank Winnefeld
Summary: This study used X-ray diffraction and Rietveld refinement technique to investigate a hydrous carbonate-containing brucite and found that the 001 reflection of this phase split into different patterns at different temperatures. The presence of water and/or carbonate influenced the distance between the layers in the brucite structure.
CEMENT AND CONCRETE RESEARCH
(2024)
Article
Construction & Building Technology
Dylan Singh, Trinh Thao My Nguyen, Evann Bustamantes, Abdul Wahab, Ahmad Hamzah Yousaf, Ian Shortt, Frank W. Foss Jr, Maria Konsta-Gdoutos, Sang Soo Lee, Erika La Plante
Summary: This study analyzes the chemical structure and morphology of magnesium silicate hydrate (MSH) grown under different concentration ratios and temperatures. The results show that increasing the magnesium to silicon ratio reduces silicate polymerization in MSH, and at higher temperatures and longer reaction times, oriented attachment of nanoparticles and enhanced crystallinity are observed. These findings provide insights into the precise chemical synthesis of MSH and its widespread use as a binder in construction.
CEMENT AND CONCRETE RESEARCH
(2024)
Article
Construction & Building Technology
J. C. O. Zepper, S. R. van der Laan, K. Schollbach, H. J. H. Brouwers
Summary: This study presents a method to calculate the main phases of BOF slag based on chemical composition and validates the proposed final model through quantitative model assessment and validation approaches.
CEMENT AND CONCRETE RESEARCH
(2024)
Article
Construction & Building Technology
Yierfan Maierdan, Samuel J. Armistead, Rebecca A. Mikofsky, Qiqi Huang, Lola Ben-Alon, Wil V. Srubar III, Shiho Kawashima
Summary: This research investigated the effects of sodium alginate on the stability and 3D printability of kaolinite suspensions. The findings showed that sodium alginate could enhance the stability of kaolinite and improve the strength of printable mixtures, as well as shift the printability window.
CEMENT AND CONCRETE RESEARCH
(2024)
