Cement and Concrete Research最新文献_第2页

Elucidating the behavior, kinetics and mechanism of wet carbonation in ternesite 阐述了镁铁石湿碳化的行为、动力学和机理

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2026-01-21 DOI: 10.1016/j.cemconres.2026.108144

Jixin Zhang , Kai Cui , Jun Chang

In this study, the carbonation kinetics, phase development, and microstructure evolution of ternesite (C₅S₂$) phase were investigated via wet carbonation. The results indicated that ternesite exhibited remarkable carbonation reactivity, achieving approximately 95% completion of the carbonation reaction within 15 min and facilitating CO₂ sequestration exceeding 340 g per kilogram of ternesite. The main carbonation products identified were aragonite, calcite, gypsum, and silica gel (Si-gel). The carbonation kinetics conformed to the surface coverage model, with the reaction proceeding through distinct stages of acceleration, deceleration, and stabilization, ultimately resulting in the formation of a “core-shell” structure. Notably, the crystalline phase of calcium carbonate (CC) underwent spontaneous transformation during the carbonation of ternesite. It is observed that CC exhibited a polycrystalline structure and underwent a distinct phase transformation from calcite to aragonite. The resulting CC was predominantly metastable, exhibiting low crystallinity and reduced crystallite size. These characteristics are attributed to the intrinsic properties of ternesite, particularly the presence of SO₄²⁻ ions, which promote the formation and stabilization of metastable aragonite. Furthermore, the changes in crystalline and morphology of CC, induced by dissolution and re-precipitation process, disrupted the CC layer and thereby facilitated the release of another significant product, Si-gel. These distinctive carbonation behaviors suggest that ternesite has potential for broader applications, including its use as a supplementary cementitious material or as a precursor for the synthesis of high value-added products such as aragonite whiskers and nano-sized SiO₂.

本文研究了湿法碳化法对铁氏体（C5S2$）相的碳化动力学、相发育和微观结构演变的影响。结果表明，钛辉石具有显著的碳化反应活性，在15 min内完成约95%的碳化反应，每千克钛辉石的CO2固存量超过340 g。鉴定出的主要碳酸化产物为文石、方解石、石膏和硅胶。碳化动力学符合表面覆盖模型，反应过程经历了不同的加速、减速和稳定阶段，最终形成“核-壳”结构。值得注意的是，碳酸钙（CC）的结晶相在钙镁石碳酸化过程中发生了自发转变。观察到CC呈现出多晶结构，并经历了明显的方解石到文石的相变。所得到的CC主要是亚稳态的，表现出低结晶度和减小的晶粒尺寸。这些特征是由于文石的固有性质，特别是SO42−离子的存在，促进了亚稳文石的形成和稳定。此外，由溶解和再沉淀过程引起的CC晶体和形态的变化破坏了CC层，从而促进了另一重要产物Si-gel的释放。这些独特的碳化行为表明钛石具有更广泛的应用潜力，包括作为补充胶凝材料或作为合成高附加值产品（如文石晶须和纳米SiO2）的前驱体。

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引用次数: 0

Adsorption mechanism of PCE superplasticizers in alkali activated materials containing silica fume PCE高效减水剂在含硅灰碱活性材料中的吸附机理

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2026-01-21 DOI: 10.1016/j.cemconres.2026.108143

Denis Kosenko , Alexander Wetzel , Bernhard Middendorf

Fluorescence and scanning electron microscopy were used to investigate hydroxide-activated slag-silica fume-based AAM mixes containing PCE superplasticizers. By applying two distinct fluorescent markers, the competitive adsorption of two PCEs with differing charge densities was observed. The results indicate that each PCE exhibits a location-specific affinity for certain topographical features of the precursor surface, as adsorption on the amorphous material is heterogeneous and varies significantly between the superplasticizers. Through the location-dependent investigations, the PCE on particle coverage levels of the particles were approximated at specific times and correlated with rheological measurements. A high charge density causes a high initial dispersion of the paste with a rapidly decreasing effect, while a lower charge density has a weaker but more persistent effect effect. A comparison of the spatially resolved adsorption derived from the fluorescence signal with the obtained scanning electron microscopy investigations shows that the tested PCEs used attach primarily to the early formed reaction products.

采用荧光显微镜和扫描电镜对含PCE高效减水剂的氢氧化物活化渣-硅烟基AAM混合物进行了研究。应用两种不同的荧光标记，观察了两种不同电荷密度的pce的竞争吸附。结果表明，每个PCE对前驱体表面的某些地形特征表现出特定位置的亲和力，因为在非晶材料上的吸附是不均匀的，并且在不同的高效减水剂之间差异很大。通过位置相关的研究，在特定时间，颗粒覆盖水平的PCE近似与流变测量相关联。高电荷密度导致膏体初始分散度高且效果迅速降低，而低电荷密度则具有较弱但更持久的效果。由荧光信号得到的空间分辨吸附与扫描电镜观察结果的比较表明，所测试的pce主要附着在早期形成的反应产物上。

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引用次数: 0

Enhanced flowability of metakaolin-blended cement through the synergistic effect of polycarboxylate superplasticizer and retarder: Competitive adsorption and retarded hydration 通过聚羧酸型高效减水剂和缓凝剂的协同作用增强偏高岭土水泥的流动性：竞争性吸附和缓凝水化

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2026-01-19 DOI: 10.1016/j.cemconres.2026.108142

Ye Pan , Zichen Lu , Xinyang Li , Hongwei Tian , Zhen Xiang , Xiangming Kong , Zhenping Sun

The synergistic effect of polycarboxylate superplasticizer (PCE) and two typical retarders (sodium citrate (SC) and sucrose (SU)) on the flowability of metakaolin (MK)-blended cement (MKC) was investigated by mini-cone tests, rheometer, total organic carbon analysis, and calorimeter. Results show that the co-addition of retarder and PCE not only improves the initial flowability but also the flowability retention of MKC paste. Further analysis indicates that the synergistic effect on initial flowability essentially originates from the competitive adsorption of PCE and retarder. The competitive adsorption of retarder on ordinary Portland cement (OPC) could enable an increased amount of available PCE to be adsorbed on MK, which is beneficial for breaking MK agglomeration and ultimately leading to increased initial flowability. Increased flowability retention is attributed to retarded cement hydration and suppressed pozzolanic reactions of MK, which limit the formation of hydration products and the increase in new surface area, thereby slowing down the consumption of PCE.

采用微锥试验、流变仪、总有机碳分析和量热法研究了聚羧酸酯型高效减水剂（PCE）与柠檬酸钠（SC）和蔗糖（SU）两种典型缓凝剂对偏高岭土水泥（MKC）流动性的协同作用。结果表明，缓速剂与PCE的共掺不仅提高了MKC膏体的初始流动性，而且提高了其流动性保持率。进一步分析表明，对初始流动性的协同效应主要来自于PCE和缓凝剂的竞争吸附。缓凝剂在普通硅酸盐水泥（OPC）上的竞争性吸附可以增加MK上有效PCE的吸附量，有利于破坏MK的结块，最终提高初始流动性。流动性保持性的增加是由于水泥水化迟缓和MK的火山灰反应受到抑制，这限制了水化产物的形成和新表面积的增加，从而减缓了PCE的消耗。

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引用次数: 0

Fast penetration testing of printable concretes with a portable device: robustness and calibration 可打印混凝土的快速渗透测试与便携式设备：稳健性和校准

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2026-01-15 DOI: 10.1016/j.cemconres.2026.108141

L. Caneda-Martínez , M. Hassan , L. Demont , E. Keita , P. Belin , V. de Bono , R. Mesnil , J.F. Caron , B. González-Fonteboa , N. Roussel

Concrete 3D printing demands rheological control tools tailored to this emerging construction technology. Conventional rheometry is often unsuitable for routine monitoring in industrial environments. This study investigates the use of a fast penetration test with a portable device as a simple, effective method to evaluate yield stress and structuration rate of printable concretes. Emphasis is placed on robustness, assessed through measurement variability rather than absolute values. Tests on clay-based reference pastes identify probe geometries minimizing operator influence and data dispersion. Probe and sample size effects are also examined. Calibration on reference pastes establishes geometry-specific conversion factors between penetration force and yield stress. These factors are then used to monitor yield stress evolution in printed concrete, with results compared to those from a pocket vane test. Findings indicate that the fast penetration method yields more robust, consistent measurements, supporting its suitability for rheological quality control in concrete 3D printing.

混凝土3D打印需要针对这种新兴建筑技术量身定制的流变控制工具。传统的流变仪通常不适合工业环境中的常规监测。本研究探讨了使用便携式快速渗透试验作为一种简单有效的方法来评估可打印混凝土的屈服应力和结构速率。重点放在稳健性上，通过测量变异性而不是绝对值来评估。基于粘土的参考膏体测试确定探针几何形状，最大限度地减少操作员影响和数据分散。探针和样本大小的影响也进行了检查。参考膏体的校准建立了穿透力和屈服应力之间的几何特定转换因子。然后使用这些因素来监测打印混凝土中的屈服应力演变，并将结果与口袋叶片测试的结果进行比较。研究结果表明，快速渗透方法产生更稳健，一致的测量结果，支持其在混凝土3D打印流变质量控制中的适用性。

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引用次数: 0

Heterogeneous fracture toughness of aggregate-reinforced materials via efficient mesoscopic modeling 基于高效细观模型的集料增强材料非均质断裂韧性研究

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2026-01-12 DOI: 10.1016/j.cemconres.2025.108130

Aram Bahmani , Farzan Farahmand , Hadi G. Kouchaki , Zakiye Nazari , Ramin Yousefi Nooraie , M.R.M. Aliha

Accurate assessment of fracture toughness in aggregate-reinforced materials, such as concrete, is essential for predicting failure under various loading conditions. Conventional methods rely on homogeneous fracture parameters, overlooking the critical influence of mesostructural heterogeneity. We present a comprehensive framework to quantify heterogeneous fracture toughness by incorporating aggregate-scale features into finite element models. Realistic mesostructures were used to compute geometry factors and T-stress variations along the crack front, revealing substantial local variability due to aggregate dispersion and spatial randomness. By integrating these results with previously reported critical fracture loads, we determined lower and upper bounds of heterogeneous fracture toughness. Linear equations were developed to convert conventional homogeneous values into corresponding heterogeneous bounds. These findings underscore the role of mesostructure in defining fracture threshold zones. Our approach provides a generalizable methodology for evaluating fracture behavior in concrete, asphalt, and other aggregate-reinforced composites, with implications for design, performance assessment, and durability.

准确评估集料增强材料（如混凝土）的断裂韧性对于预测其在各种荷载条件下的破坏至关重要。传统方法依赖于均匀的裂缝参数，忽略了细观结构非均质性的关键影响。我们提出了一个全面的框架，量化非均质断裂韧性，将聚集尺度特征纳入有限元模型。利用真实的细观结构计算几何因子和沿裂缝前沿的t应力变化，揭示了由于聚集分散和空间随机性而产生的大量局部变异性。通过将这些结果与先前报道的临界断裂载荷相结合，我们确定了非均质断裂韧性的下限和上限。建立了线性方程，将传统的齐次值转化为相应的异质边界。这些发现强调了介观结构在确定断裂阈值区的作用。我们的方法为评估混凝土、沥青和其他骨料增强复合材料的断裂行为提供了一种通用的方法，对设计、性能评估和耐久性具有指导意义。

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引用次数: 0

Evaluation of atmospheric CO₂ sequestration by 50-year-old concrete structures based on 14C and 13C measurements 基于14C和13C测量的有50年历史的混凝土结构对大气CO 2封存的评价

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2026-01-10 DOI: 10.1016/j.cemconres.2025.108129

Ippei Maruyama , Haruka Takahashi , Yoshihiro Asahara , Hidekazu Yoshida , Abudushalamu Aili , Masayo Minami

This study examines the long-term sequestration of atmospheric CO₂ as an inorganic carbonate through carbonation in concrete structures. Two buildings, each approximately 50 years old, were analyzed using two cores per structure. Measurements of radiocarbon (¹⁴C) concentration, δ¹³C, and total inorganic carbon (TIC) of the core samples were conducted. For one building containing limestone aggregate, additional analyses, visual inspection, polarized light microscopy, and X-ray diffraction with Rietveld refinement were performed to evaluate the material and mineral distributions. The results indicate that δ¹³C varies with pH changes during carbonation, while the concentration of ¹⁴C reflects the historical fluctuations in atmospheric ¹⁴C. By applying the √t relationship for carbonation depth, the amount of CO₂ fixed from the atmosphere can be determined, even in the presence of limestone aggregate. This study provides a methodology for assessing long-term CO₂ sequestration in existing concrete structures.

本研究考察了通过混凝土结构中的碳化作用对大气中二氧化碳作为无机碳酸盐的长期封存。两栋大约有50年历史的建筑，每个结构使用两个核心进行分析。测定了岩心样品的放射性碳（14C）浓度、δ13C和总无机碳（TIC）。对于一个含有石灰石骨料的建筑，进行了额外的分析、目视检查、偏振光显微镜和Rietveld细化的x射线衍射来评估材料和矿物分布。结果表明，碳酸化过程中δ13C随pH变化而变化，而14C浓度反映了大气14C的历史波动。通过应用碳酸化深度的√t关系，可以确定大气中固定的CO₂的量，即使存在石灰石骨料。该研究为评估现有混凝土结构的长期CO₂封存提供了一种方法。

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引用次数: 0

Pore-scale simulation of reactive transport processes at the steel–concrete interface 钢-混凝土界面反应输运过程的孔隙尺度模拟

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2026-01-09 DOI: 10.1016/j.cemconres.2026.108132

Thilo Schmid , O. Burkan Isgor , Ueli Angst

Corrosion of steel in concrete involves complex transport and (electro-) chemical processes at the steel–concrete interface (SCI). Reactive transport modeling is a powerful tool to investigate these mechanisms and has strong potential to provide critical insights into corrosion-related deterioration and thereby contribute to ensuring the durability of traditional and modern low-carbon concretes. Traditional reactive transport models use homogenization techniques that are computationally efficient but overlook the detailed pore structure at the SCI. Our study introduces an approach that leverages high-resolution FIB-SEM nanotomograms to create discretized finite element domains, enabling direct pore-scale reactive transport modeling. We showcase selected examples involving aqueous species relevant to corrosion, including corrosion product precipitation in the interfacial pore network. Simulation results demonstrate that pore structure gives rise to significant local variations in concentrations and precipitate formation, thereby explaining the heterogeneity of corrosion phenomena in cementitious materials. Notably, narrow pores acting as transport bottlenecks caused local aqueous

accumulation, promoting

precipitation in contrast to more open regions. For comparison, a homogenized model – using independently computed diffusion tortuosity and porosity from 3D pore structures – was implemented. Remarkably, without parameter fitting, this model captured average trends but failed to resolve key localized phenomena like early corrosion product precipitation. We conclude that explicitly modeling pore-scale structures is essential for accurately capturing reactive transport processes at the SCI. Our framework offers a path towards more accurate simulation of micron- and sub-micron scale processes, challenging simplifying assumptions in traditional models, and emphasizing the need for incorporating local structural features at the SCI in corrosion modeling.

钢筋在混凝土中的腐蚀涉及复杂的钢-混凝土界面（SCI）传输和（电）化学过程。反应输运模型是研究这些机制的有力工具，具有强大的潜力，可以提供与腐蚀相关的恶化的关键见解，从而有助于确保传统和现代低碳混凝土的耐久性。传统的反应输运模型使用均匀化技术，计算效率高，但忽略了SCI的详细孔隙结构。我们的研究引入了一种方法，利用高分辨率FIB-SEM纳米层析成像来创建离散的有限元域，从而实现直接的孔隙尺度反应输运建模。我们展示了一些与腐蚀有关的水性物质的例子，包括界面孔隙网络中的腐蚀产物沉淀。模拟结果表明，孔隙结构会引起局部浓度和沉淀形成的显著变化，从而解释了胶凝材料中腐蚀现象的异质性。值得注意的是，与更开放的区域相比，狭窄的孔隙作为运输瓶颈导致了局部水积累，促进了降水。为了进行比较，采用了一种均质模型——使用独立计算的三维孔隙结构的扩散弯曲度和孔隙度。值得注意的是，在没有参数拟合的情况下，该模型捕获了平均趋势，但未能解决关键的局部现象，如早期腐蚀产物沉淀。我们得出结论，明确地模拟孔隙尺度结构对于准确捕获SCI的反应性输运过程至关重要。我们的框架为更精确地模拟微米和亚微米尺度过程提供了一条途径，挑战了传统模型中简化的假设，并强调了在腐蚀模型中纳入SCI局部结构特征的必要性。

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引用次数: 0

Effect of Al/Si ratio on the reactivity of waste- and two-step carbonation-derived alumina-silica gel 铝硅比对废二步碳化衍生铝硅凝胶反应性的影响

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2026-01-08 DOI: 10.1016/j.cemconres.2025.108131

Shunmin Xiao, Yi Jiang, Zihan Ma, Long Jiang, Jionghuang He, Qi Liu, Peiliang Shen, Chi Sun Poon

Alumina-silica gels are highly reactive pozzolans derived from the carbonation of solid waste containing calcium and aluminosilicate. Their microstructure and reactivity are critically influenced by the Al/Si ratio, which in turn varies greatly depending on the original composition of the raw materials. In this study, alumina-silica gels with Al/Si ratios of 0.01–0.91 were synthesized through a two-step carbonation process, aiming at revealing their differences in pozzolanic reactivity. Findings indicate that their pozzolanic reactivity and reaction pathways were governed by chemical composition, AlSi microstructural configuration, and resulting physical properties. An Al/Si ratio of 0.01 resulted in a gel with the highest porosity and specific surface area, as well as the lowest particle size. This gel rapidly formed C–S–H and nearly completed the reaction within 1 d, releasing the highest cumulative heat of 764.9 J/g during its reaction with calcium hydroxide. However, when the Al/Si ratio increased to 0.35, the gel reacted more slowly and exhibited two low-intensity exothermic peaks of 1.7 and 0.6 mW/g that were associated with C–A–S–H and strätlingite formation, respectively. Despite similar compositions and physical properties, gels differed in depolymerization and reaction rates. This was because the incorporation of Na acted as charge-balancing ions when Al tetrahedra replaced some of the Si tetrahedra. Particularly, for the gel with the highest Al/Si ratio of 0.91, its rich Na content greatly accelerated depolymerization. This caused a sharp increase in heat release between 12 and 60 h (218.2 J/g), with strätlingite as the main product.

铝硅凝胶是由含钙和硅酸铝的固体废物碳化而成的高活性火山灰。它们的微观结构和反应性受到Al/Si比的严重影响，而Al/Si比又因原材料的原始成分而有很大变化。本研究通过两步碳化法合成了Al/Si比值为0.01-0.91的氧化铝-硅胶，旨在揭示它们在火山灰反应性上的差异。研究结果表明，它们的火山灰反应活性和反应途径受化学成分、AlSi微观结构构型和所产生的物理性质的控制。Al/Si比为0.01时，凝胶的孔隙率和比表面积最高，粒径最小。该凝胶快速生成C-S-H，并在1 d内基本完成反应，与氢氧化钙反应时释放的累积热量最高，为764.9 J/g。然而，当Al/Si比增加到0.35时，凝胶反应变慢，并表现出两个低强度放热峰，分别与C-A-S-H和strätlingite的形成有关，分别为1.7和0.6 mW/g。尽管组成和物理性质相似，但凝胶的解聚和反应速率不同。这是因为当Al四面体取代一些Si四面体时，Na的加入起到了电荷平衡离子的作用。特别是Al/Si比最高的凝胶为0.91，其丰富的Na含量大大加速了解聚。这导致热释放在12至60 h之间急剧增加（218.2 J/g），以strätlingite为主要产品。

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引用次数: 0

Unravelling chemical-microstructural pathways of deformation in MgO-fly ash cementitious systems mgo -粉煤灰胶凝体系中变形的化学-微观结构路径揭示

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2026-01-03 DOI: 10.1016/j.cemconres.2025.108128

Shuai Ding , Cise Unluer , Kai Li , Yanlong Ren , Ning Li , Zhangli Hu , Jiaping Liu

MgO expansive agents (MEA) and fly ash (FA) are widely combined to mitigate shrinkage in concrete, yet their interaction mechanisms remain unclear. This study clarifies how FA regulates MEA-induced expansion through microstructural evolution and pore solution chemistry, with swelling and crystallization pressures identified as the driving forces. At early stages, FA lowered pH, elevated Mg²⁺ concentration, accelerating periclase hydration. Higher mesoporosity enlarged dissolution interface, promoted formation of finer brucite with stronger water adsorption capacity, increasing swelling pressure. At later stages, pozzolanic reaction of FA reduced portlandite formation, diminishing spatial confinement near MEA and alleviating crystallization pressure. Suppressed portlandite barriers and enhanced Mg²⁺ mobility promoted brucite precipitation into surrounding voids, refining pore structure and improving dimensional stability. This work extends understanding of MEA-induced deformation to a coupled chemical–microstructural level and shows that FA regulates expansion driving forces through ionic and microstructural interactions, establishing a framework for achieving full-stage shrinkage compensation.

MgO膨胀剂（MEA）和粉煤灰（FA）被广泛用于减缓混凝土收缩，但它们的相互作用机制尚不清楚。本研究阐明了FA如何通过微观结构演化和孔溶液化学来调控mea诱导的膨胀，膨胀压力和结晶压力被确定为驱动力。早期FA降低了pH，升高了Mg2+浓度，加速了方石酶的水化。介孔率越高，溶解界面越大，水镁石越细，吸附能力越强，溶胀压力越大。在后期，FA的火山灰反应减少了波特兰岩的形成，减少了MEA附近的空间限制，减轻了结晶压力。抑制波特兰岩屏障，增强Mg2+迁移率，促进水镁石向周围空隙中析出，改善孔隙结构，提高尺寸稳定性。这项工作将对mea引起的变形的理解扩展到化学-微观结构的耦合水平，并表明FA通过离子和微观结构的相互作用调节膨胀驱动力，建立了实现全阶段收缩补偿的框架。

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引用次数: 0

Adsorption phenomena and surface interactions between superplasticisers and ground blast furnace slag and metakaolin particles in alkali solutions: Implications for low-carbon cements 碱溶液中高效增塑剂与高炉矿渣和偏高岭土颗粒的吸附现象和表面相互作用：对低碳水泥的影响

IF 13.1 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Cement and Concrete Research

Pub Date : 2026-01-02 DOI: 10.1016/j.cemconres.2025.108127

Micael Rubens Cardoso da Silva , Jiahui Qi , Ian Ross , Ana Paula Kirchheim , Brant Walkley

The performance of superplasticisers in alkali-activated materials (AAMs) remains poorly understood, limiting the wider adoption of low-carbon cement technologies. This study examines the behaviour of lignosulfonate- (LS), naphthalene- (NP), and polycarboxylate ether (PCE)-based superplasticisers in NaOH/Na₂SiO₃-activated systems with ground granulated blast furnace slag (GGBFS) and metakaolin (MK). The adsorption phenomena and polymer conformation were investigated by combining mini-slump tests (flow behaviour), ATR-FTIR (chemical interactions), DLS (polymer size), TEM-EDX (polymer conformation), zeta potential measurements (surface charge), and total organic carbon analysis (polymer uptake). Results show that in both GGBFS and MK systems, high alkalinity alters polymer ionisation, suppresses electrostatic interactions, reduces superplasticiser solubility, and drives polymer agglomeration. In GGBFS systems, Ca²⁺ enhances superplasticiser adsorption to solid particles. LS-based superplasticisers demonstrated superior alkaline resistance, slump retention, and adsorption capacity relative to NP and PCE. These findings provide new mechanistic insights to guide the design of high-performance superplasticisers tailored for low-carbon AAM systems.

碱活化材料（AAMs）中超塑化剂的性能仍然知之甚少，这限制了低碳水泥技术的广泛采用。本研究考察了木质磺酸盐- (LS)、萘- (NP)和聚羧酸醚（PCE）基高效增塑剂在NaOH/Na₂SiO₃活化体系中的行为，该体系含有磨粒高炉渣（GGBFS）和偏高岭土（MK）。通过结合微坍落度测试（流动行为）、ATR-FTIR（化学相互作用）、DLS（聚合物尺寸）、TEM-EDX（聚合物构象）、zeta电位测量（表面电荷）和总有机碳分析（聚合物吸收），研究了吸附现象和聚合物构象。结果表明，在GGBFS和MK体系中，高碱度改变了聚合物的电离，抑制了静电相互作用，降低了超塑剂的溶解度，并促进了聚合物的团聚。在GGBFS系统中，Ca2+增强了超塑剂对固体颗粒的吸附。与NP和PCE相比，ls基高效减水剂具有更强的耐碱性、坍落度保持和吸附能力。这些发现为指导低碳AAM体系高性能高效减水剂的设计提供了新的机理见解。

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引用次数: 0