Cement and Concrete Research最新文献

Effect of phase composition on the reactivity of DRI-EAF slags as SCM 相组成对dr - eaf炉渣反应性的影响

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

Cement and Concrete Research

Pub Date : 2026-05-01 Epub Date: 2026-02-11 DOI: 10.1016/j.cemconres.2026.108160

Morteza Tayebi , Katrin Schollbach , J.C.O. Zepper , Stefan Melzer , H.J.H. Brouwers

DRI in EAFs will reduce the availability of blast-furnace slag, necessitating alternative SCMs. Five DRI–EAF slags (four engineered, and one industrial) were investigated, spanning CaO/SiO₂ ≈ 1.3 or 2.0, FeOx ≈25 or 40 wt%, and cooling (air-cooled vs water-granulated). At 25 wt% clinker replacement, hydration and performance were quantified by isothermal and R³ calorimetry, UPV, autogenous shrinkage, XRD/TGA, compressive strength, and leaching. Cooling history, through the control of the amorphous fraction, governed reactivity: water-granulated slags exhibited higher cumulative heat, accelerated set, and superior strength activity indices compared to air-cooled analogues. Basicity and FeOx exerted secondary effects: higher basicity accelerated hydration and reduced autogenous shrinkage, whereas elevated FeOx retarded reaction. All binders formed C–S–H, ettringite, and portlandite; hydrotalcite-like LDHs were detected only for the low-basicity, water-granulated slag. All mortars complied with Dutch leaching limits and met SCM strength benchmarks, evidencing the viability of engineered DRI–EAF slags as low-CO₂ cementitious binders.

电炉的DRI将减少高炉炉渣的可用性，需要替代SCMs。研究了五种DRI-EAF渣（四种工程渣，一种工业渣），CaO/SiO₂≈1.3或2.0，FeOx≈25或40 wt%，冷却（风冷vs水粒化）。在25 wt%的熟料替代下，通过等温和R3量热法、UPV、自收缩、XRD/TGA、抗压强度和浸出来量化水化和性能。通过控制非晶部分的冷却历史，控制了反应性：与风冷类似物相比，水粒化炉渣表现出更高的累积热量、加速凝固和优越的强度活性指标。碱度和FeOx具有次要作用：较高的碱度加速了水化反应，降低了自缩水率，而较高的FeOx则延缓了反应。所有粘结剂均形成C-S-H、钙矾石和波特兰石；仅在低碱度、水粒化的矿渣中检测到类水滑石LDHs。所有砂浆均符合荷兰浸出限值，并达到SCM强度基准，证明了工程化的DRI-EAF渣作为低co₂胶凝粘合剂的可行性。

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引用次数: 0

Understanding the rheology of non-calcium metakaolin geopolymers from chemical and floc-structural perspectives: Effects of silicate concentration and alkalinity 从化学和絮团结构角度了解非钙偏高岭土聚合物的流变性：硅酸盐浓度和碱度的影响

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

Cement and Concrete Research

Pub Date : 2026-05-01 Epub Date: 2026-02-10 DOI: 10.1016/j.cemconres.2026.108158

Song Xiang , Huanchun Cai , Prannoy Suraneni , Xu Chen

The rheology of fresh geopolymers is primarily governed by Si content and alkalinity, yet the underlying mechanism in Ca-free systems remains insufficiently understood. Metakaolin geopolymers with (0–1) Na₂O:1Al₂O₃:(2–4) SiO₂:14H₂O were investigated through rheological, microstructural, and spectroscopic characterizations. Yield stress peaked at 2.4 mol SiO₂ and 0.3 mol Na₂O. At these maxima, flocculated networks showed diminished roundness (<0.25) and increased fractal dimension (~1.67), alongside maximal dissolved Al concentrations (0.11 and 0.06 mol/L), signifying gelation-driven structural complexity. As Si content and alkalinity further increased, FTIR–ICP analyses revealed that progressive enrichment of surface-adsorbed Si/Al drove condensation to its temporary limit, while precipitating low-polymerized sodium silicates. This precipitation attachment enhanced roundness, reduced fractal dimension, and thus pronouncedly decreased yield stress. In silicate-activated systems, continued Si enrichment generated unstable silica-rich layers, as declining yield stress gradually stabilized. Collectively, these findings establish a mechanistic framework that simultaneously links rheology to floc structures and interfacial chemistry.

新鲜地聚合物的流变性主要受Si含量和碱度的影响，但其在无ca体系中的潜在机制尚不清楚。通过流变学、微观结构和光谱表征研究了（0-1）Na2O:1Al2O3:(2-4) SiO2:14H2O的偏高岭土聚合物。屈服应力在2.4 mol SiO2和0.3 mol Na2O时达到峰值。在这些最大值处，絮凝网络的圆度减小（<0.25），分形维数增加（~1.67），溶解Al浓度最大（0.11和0.06 mol/L），表明凝胶驱动的结构复杂性。随着Si含量和碱度的进一步增加，FTIR-ICP分析显示，表面吸附的Si/Al逐渐富集，导致缩聚达到暂时的极限，同时沉淀低聚合的硅酸钠。这种沉淀附着增强了圆度，降低了分形维数，从而明显降低了屈服应力。在硅酸盐活化体系中，随着屈服应力的逐渐稳定，持续的硅富集产生了不稳定的富硅层。总的来说，这些发现建立了一个机制框架，同时将流变学与絮团结构和界面化学联系起来。

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引用次数: 0

Comparative study on phosphogypsum-based cemented paste backfill prepared with ordinary Portland cement and calcium aluminate cement: Correlations among macroscopic properties, thermodynamic behavior and hydration mechanism 普通硅酸盐水泥与铝酸钙水泥制备磷石膏基胶结体充填体的对比研究：宏观性能、热力学行为及水化机理的相关性

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

Cement and Concrete Research

Pub Date : 2026-05-01 Epub Date: 2026-02-10 DOI: 10.1016/j.cemconres.2026.108161

Qiusong Chen , Tianjiao Yu , Daolin Wang , Bin Liu , Yan Feng , Qinli Zhang , Yikai Liu

Calcium aluminate cement (CAC), characterized by superior properties and low-carbon emission, shows strong potential to replace traditional ordinary Portland cement (OPC) in in-situ phosphogypsum (PG) backfill. Although the microstructural characteristics and pollutant immobilization have been investigated, its hydration kinetics, microstructural evolution, and carbon reduction behavior remain insufficiently explored. This study aims to investigate the intrinsic links between hydration mechanisms and macroscopic properties. The flowability, setting behavior, strength development, hydration characteristics and carbon footprints of CAC-based and OPC-based backfill systems were systematically evaluated through experiments and thermodynamic simulations. The results show that PG alters the hydration of CAC, exerting a dual effect on its macroscopic properties. Thermodynamic simulations indicate sequential formation of amorphous Al (OH)₃, ettringite and OH-hydrotalcite, with synergistic interactions enhance strength development. The comparison of both systems shows that differences in product types, formation conditions and interactions fundamentally govern their macroscopic variations.

铝酸钙水泥（CAC）具有优异的性能和低碳排放，在原位磷石膏（PG）充填中具有取代传统普通硅酸盐水泥（OPC）的巨大潜力。虽然对其微观结构特征和污染物固定化进行了研究，但对其水化动力学、微观结构演化和碳还原行为的探索还不够充分。本研究旨在探讨水化机制与宏观性能之间的内在联系。通过实验和热力学模拟，系统评价了活性炭基和opc基充填体的流动性、凝结特性、强度发展、水化特性和碳足迹。结果表明，PG改变了CAC的水化，对其宏观性能产生了双重影响。热力学模拟表明，无定形Al (OH)3、钙矾石和OH-水滑石依次形成，协同作用增强了强度的发展。两种体系的比较表明，产物类型、形成条件和相互作用的差异从根本上决定了它们的宏观变化。

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引用次数: 0

Pore solution matching: A method to resolve superplasticizer distributions in blended cements 孔隙溶液匹配：一种解决混合水泥中高效减水剂分布的方法

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

Cement and Concrete Research

Pub Date : 2026-05-01 Epub Date: 2026-02-07 DOI: 10.1016/j.cemconres.2026.108149

Sirajuddin Moghul , Léa Köller , Astrid Sidos , Franco Zunino , Robert J. Flatt

In blended cements, superplasticizers may distribute unevenly between the different mineral components, a challenge compounded by the heterogeneity of supplementary cementitious materials (SCMs). While it is understood that this may impact both rheology and hydration kinetics, the topic has not yet been addressed either systematically or quantitatively. This study does this by developing a quantitative framework called Pore Solution Matching (PSM), which enables systematic characterization superplasticizer distribution in multicomponent binders, using limestone calcined clay cement (LC3) as a representative system. This is done by using a polycarboxylate ether (PCE) and a diphosphonate superplasticizers. Protocols are established to conduct adsorption studies on the individual components of LC3, clinker, calcined clay, and limestone, to obtain results that represent an early-age LC3 paste. Integrating such data into a surface-based mass balance model it is possible to reconstruct polymer distributions and surface coverages across the different phases in LC3. As revealed by isothermal calorimetry this has important implications on hydration kinetics. Specifically, it is shown that the retardation response of LC3 varies linearly with the surface coverage of OPC by either of the superplasticizer used.

Though demonstrated here for LC3, the methodology and insights presented are applicable to a broad class of SCM-rich binders, offering a generalizable strategy for admixture design in a broad range of cementitious systems, including but not limited to low carbon cements.

在混合水泥中，高效减水剂可能在不同矿物组分之间分布不均匀，而补充胶凝材料（SCMs）的非均质性使这一挑战更加严峻。虽然可以理解这可能会影响流变学和水化动力学，但该主题尚未得到系统或定量的解决。本研究通过开发一种称为孔隙溶液匹配（PSM）的定量框架来实现这一目标，该框架使用石灰石煅烧粘土水泥（LC3）作为代表系统，可以系统地表征高减水剂在多组分粘合剂中的分布。这是通过使用聚羧酸醚（PCE）和二膦酸盐高效减水剂来完成的。建立了对LC3、熟料、煅烧粘土和石灰石的各个组分进行吸附研究的方案，以获得代表早期LC3浆料的结果。将这些数据整合到基于表面的质量平衡模型中，可以重建LC3中不同相的聚合物分布和表面覆盖率。等温量热法表明，这对水化动力学具有重要意义。结果表明，LC3的缓速响应随两种高效减水剂对OPC表面覆盖的影响呈线性变化。虽然这里展示的是LC3，但所提出的方法和见解适用于广泛的一类富含scm的粘合剂，为广泛的胶凝系统（包括但不限于低碳水泥）的外加剂设计提供了一种通用策略。

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引用次数: 0

Carbon-negative magnesium-based manufactured aggregates development for carbon negative cement-based materials 负碳镁基人造骨料在负碳水泥基材料中的应用

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

Cement and Concrete Research

Pub Date : 2026-05-01 Epub Date: 2026-02-10 DOI: 10.1016/j.cemconres.2026.108147

Xi Chen , Dhanendra Kumar , En-Hua Yang

An alternative approach to developing low-carbon concrete is through carbon mineralization in aggregates. This research focuses on carbon mineralized magnesium (Mg)-based manufactured aggregates. First, a low-carbon synthesis process for brucite [Mg(OH)₂] and the incorporation of silica fume to enhance the strength and carbon sequestration capacity were investigated. The 25% (by weight) of silica fume improved the mechanical strength (~31 MPa) and carbon sequestration capacity (~26 wt%) of manufactured aggregates. The underlying chemical and microstructural characterizations showed that silica fume acts as an inert filler. Carbon emission assessments yielded a negative carbon footprint of 0.186 kg CO₂/kg of aggregates. The 50% volumetric replacement of natural fine aggregates with manufactured aggregates in 50 MPa concrete retained the compressive strength, while also achieving a 10% reduction in embodied carbon. In the case of 20 MPa mortar, 100% of natural fine aggregates could be replaced with Mg-based manufactured aggregates developed in his study.

开发低碳混凝土的另一种方法是通过骨料中的碳矿化。本研究的重点是碳矿化镁（Mg）基人造骨料。首先，研究了水镁石[Mg(OH)2]的低碳合成工艺，并研究了硅灰的掺入以提高水镁石的强度和固碳能力。25%（重量）的硅灰提高了合成集料的机械强度（~31 MPa）和固碳能力（~26 wt%）。基础化学和微观结构表征表明，硅灰作为一种惰性填料。碳排放评估得出的负碳足迹为0.186 kg CO₂/kg骨料。在50 MPa的混凝土中，用人造骨料代替50%的天然细骨料，保留了抗压强度，同时也实现了10%的碳减排。在20mpa砂浆条件下，研制的mg基人造骨料可替代100%的天然细骨料。

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引用次数: 0

An advanced understanding for synergistic effect of limestone and ethanol di-isopropanolamine on slag-limestone ternary cement 石灰石与乙醇二异丙醇胺对矿渣-石灰石三元水泥增效作用的进一步认识

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

Cement and Concrete Research

Pub Date : 2026-05-01 Epub Date: 2026-02-12 DOI: 10.1016/j.cemconres.2026.108172

Jihoon Lee , Franco Zunino , Juhyuk Moon

The use of limestone can mitigate the limited availability of supplementary cementitious materials while reducing the clinker factor, but it often decreases strength. This study demonstrates that ethanoldiisopropanolamine (EDIPA) enables an increase in strength of slag-limestone cement. EDIPA facilitated the aluminate reaction, enhancing the formation of monocarbonate and ettringite in limestone-containing binder. Meanwhile, additional aluminates were preferentially incorporated into C–A–S–H rather than AFm phases in limestone-free binder. EDIPA improved the slag reactivity, increasing C–A–S–H precipitation with a lower Ca/Si ratio and a higher Al/Si ratio. Although neither EDIPA nor limestone influenced early sulfate adsorption on C–A–S–H, they seem to cause its desorption, resulting in additional ettringite formation at later ages. Consequently, EDIPA did not improve the strength of the limestone-free binder, but the combined increase in hydration products by EDIPA and limestone refined the pore structure and enhanced the strength, exceeding that of limestone-free binder despite a 20% limestone replacement.

石灰石的使用可以缓解补充胶凝材料的有限可用性，同时降低熟料系数，但通常会降低强度。本研究表明，乙醇二异丙醇胺（EDIPA）能够提高矿渣-石灰石水泥的强度。EDIPA促进了铝酸盐反应，促进了含石灰石粘结剂中单碳酸盐和钙矾石的生成。同时，在无石灰石粘结剂中，额外的铝酸盐优先掺入C-A-S-H相，而不是AFm相。EDIPA提高了渣的反应性，增加了C-A-S-H的析出量，降低了Ca/Si比，提高了Al/Si比。虽然EDIPA和石灰岩都没有影响早期硫酸盐在C-A-S-H上的吸附，但它们似乎引起了硫酸盐的解吸，导致后期形成额外的钙矾石。因此，EDIPA并没有提高无石灰石粘结剂的强度，但EDIPA与石灰石水化产物的共同增加细化了孔隙结构，提高了强度，即使添加20%的石灰石，也超过了无石灰石粘结剂的强度。

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引用次数: 0

Aqueous carbonation-induced self-healing of UHPFRC: Role of sulfur/magnesium-rich expansive agents in crack closure and mechanical restoration 水碳化诱导UHPFRC自愈：富硫/富镁膨胀剂在裂纹闭合和力学修复中的作用

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

Cement and Concrete Research

Pub Date : 2026-05-01 Epub Date: 2026-02-05 DOI: 10.1016/j.cemconres.2026.108159

Qiaomu Zheng , En-Hua Yang , Yanqun Xu , Chen Li , Xinping Zhu , Zuhua Zhang , Zhengwu Jiang

By incorporating characteristic expansive agents, the crack self-healing capability of UHPFRC under aqueous carbonation is enhanced. Synergistic use of sulfur (ye'elimite-based, S-EA)- and magnesium (periclase-based, M-EA)-rich expansive agents reduces the capillary pore content/size through crystalline filling while increasing the gel pore volume by hydration promotion. Such a dual influence balances the overall chemical stability and the surface ion exchange capacity of UHPFRC. Post-cracking, slower periclase hydration from M-EA sustains the alkalinity of crack solution, thus stimulating secondary hydration and subsequent self-healing. S-EA-derived ettringite improves the spatial uniformity of self-healing products by templating the oriented carbonate nucleation during the early carbonation, whereas M-EA-derived brucite promotes the crack closure via prolonging the crack solution supersaturation and facilitating the calcite-aragonite intergrowth. During the later carbonation, Mg-calcite contributes to enhanced nanomechanical properties and modulated failure modes of self-healing products through localized lattice stress fields. Aragonite further reconstructs a more integrated self-healing phase-quartz aggregate interface through the reduction of lattice mismatches. These two mechanisms collectively reinforce the mechanical property restoration of UHPFRC.

通过加入特征膨胀剂，提高了UHPFRC在水碳酸化作用下的裂缝自愈能力。富硫（ye' elimte -based, S-EA）和富镁（periclase-based, M-EA）膨胀剂的协同使用通过晶体填充减少了毛细管孔隙含量/大小，同时通过水化促进增加了凝胶孔隙体积。这种双重影响平衡了UHPFRC的整体化学稳定性和表面离子交换能力。开裂后，M-EA较慢的方解石水化维持了裂纹溶液的碱性，从而刺激了二次水化和随后的自愈。s - ea衍生钙矾石在碳酸化早期通过模板化碳酸盐定向成核提高了自愈产物的空间均匀性，而m - ea衍生水镁石通过延长裂缝溶液过饱和期和促进方解石-文石共生来促进裂缝闭合。在碳酸化后期，镁方解石通过局部点阵应力场增强了纳米力学性能，并调节了自愈产物的破坏模式。文石通过减少晶格错配进一步重建了一个更完整的自愈相-石英聚集界面。这两种机制共同加强了UHPFRC的力学性能恢复。

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引用次数: 0

Chemical and mechanical origin of ettringite morphology and packing properties 钙矾石形态和堆积特性的化学和力学成因

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

Cement and Concrete Research

Pub Date : 2026-05-01 Epub Date: 2026-02-05 DOI: 10.1016/j.cemconres.2026.108146

Laura Caneda-Martínez , Hela Bessaies-Bey , Xiaohan Yu , Karen Mourda , Patrick Belin , Belén González-Fonteboa , Nicolas Roussel

The contribution of early hydration products is often neglected in rheological studies of cementitious systems, particularly with respect to the quantitative evaluation of their influence on particle packing. Ettringite, owing to its predominance as an early-age hydration product and its frequently elongated morphology, is the most relevant phase to consider in this context. This study investigates the factors controlling ettringite morphology in the absence of admixtures and evaluates their impact on packing behaviour. Ettringite was synthesised under controlled solution conditions and analysed via microscopic techniques to assess the effect of ion concentration on morphology. In addition, the packing properties of ettringite samples of different morphology were studied by applying controlled compressive stress through centrifugation experiments. Results show that ettringite morphology is defined by solution supersaturation with respect to ettringite and mechanical stress: reduced supersaturation (i.e. dilution of the system) favours the formation of longer, thinner crystals, while stress induces breaking, with the resulting aspect ratio of the crystals dictated by the magnitude of the applied stress. Ettringite crystals were found to exhibit poor packing properties compared to those of common building materials. Moreover, a clear correlation between aspect ratio and packing properties was identified, consistent with predictive models for elongated macroscopic particles. These findings have significant practical implications, as understanding and controlling ettringite morphology can provide an effective means to tune early-age rheology in cement-based materials. We finally suggest that these findings are specifically relevant for low-clinker content binders where supersaturation is expected to be lower than traditional binders.

在胶凝体系的流变学研究中，早期水化产物的贡献常常被忽视，特别是在定量评估它们对颗粒堆积的影响方面。钙矾石，由于其作为早期水化产物的优势和其经常拉长的形态，是在这种情况下最相关的相考虑。本研究探讨了在没有外加剂的情况下控制钙矾石形态的因素，并评估了它们对堆积行为的影响。在控制溶液条件下合成了钙矾石，并通过显微技术分析了离子浓度对其形貌的影响。另外，通过离心实验对不同形貌的钙矾石试样施加可控压应力，研究了其充填性能。结果表明，钙矾石的形态是由钙矾石的溶液过饱和和机械应力决定的：过饱和的降低（即系统的稀释）有利于形成更长、更薄的晶体，而应力则导致破裂，晶体的长径比由施加应力的大小决定。与普通建筑材料相比，钙矾石晶体表现出较差的堆积性能。此外，还发现了纵横比与堆积性能之间的明显相关性，这与拉长宏观颗粒的预测模型相一致。这些发现具有重要的实际意义，因为了解和控制钙矾石的形态可以为调整水泥基材料的早期流变性提供有效的手段。我们最后建议，这些发现是特别相关的低熟料含量粘合剂，其中过饱和预期低于传统粘合剂。

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引用次数: 0

The Matthew effect in cement hydration: Hydroxylation-driven wetting of C2S mesopores 水泥水化中的马修效应：氢化驱动的C2S介孔润湿

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

Cement and Concrete Research

Pub Date : 2026-05-01 Epub Date: 2026-02-05 DOI: 10.1016/j.cemconres.2026.108154

Gen Li, Xiong Qian, Yining Gao, Peiliang Shen, Yong Tao, Chi Sun Poon

Water adsorption and capillary condensation in cementitious mesopores govern early transport and hydration kinetics, yet how surface chemistry couples to pore wetting remains unclear. Using grand canonical Monte Carlo simulations, we quantify water uptake and condensation in slit-shaped dicalcium silicate mesopores with varying surface hydroxylation degree. We identify a Matthew effect in hydration, i.e., a positive-feedback process in which water accumulation promotes surface hydroxylation, which in turn strengthens solid-liquid interactions and accelerates further uptake. The enhanced water adsorption on hydroxylated surfaces arises from more interfacial hydrogen bonds and shorter bonding distances, increasing the orientational ordering and structuring of interfacial water. Therefore, more reactive minerals develop more hydroxylated surfaces that increase water uptake and promote further hydration, exacerbating interphase heterogeneity in the hydration degree of cement paste. These results clarify the preferential transport and accumulation of water in cement mesopores and provide explanations for long-term hydration degree disparities of clinker phases.

水在胶凝介孔中的吸附和毛细凝结控制着早期的运输和水化动力学，但表面化学如何耦合到孔隙润湿仍然不清楚。利用大规范蒙特卡罗模拟，我们量化了具有不同表面羟基化程度的狭缝状硅酸二钙介孔中的吸水和凝结。我们确定了水合作用中的马太效应，即一个正反馈过程，在这个过程中，水的积累促进了表面羟基化，这反过来加强了固液相互作用并加速了进一步的吸收。羟基化表面对水的吸附增强是由于界面氢键的增加和键距的缩短，界面水的取向有序和结构增加。因此，更多活性矿物形成更多的羟基化表面，从而增加水吸收并促进进一步水化，加剧了水泥浆体水化程度的相间不均匀性。这些结果阐明了水在水泥介孔中的优先运输和积累，并为熟料相水化程度的长期差异提供了解释。

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引用次数: 0

Speciation of Mn in electric arc furnace clinker 电弧炉熟料中Mn的形态

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

Cement and Concrete Research

Pub Date : 2026-05-01 Epub Date: 2026-02-14 DOI: 10.1016/j.cemconres.2026.108162

Jianhang Feng , Shiju Joseph , Mingrui Yang , Tatjana Jantzen , Klaus Hack , Rohit Prajapati , Zushu Li , Cyrille F. Dunant , Rupert J. Myers

Co-producing clinker and steel during electric arc furnace (EAF) steelmaking is an emerging pathway to reduce carbon emissions in cement production. However, several elements in steel may compromise EAF clinker performance. This study investigated the distribution of Mn in EAF clinker produced from normal steel scrap. The results reveal that these EAF clinkers contained 7–8 wt% Mn oxide and Mn in divalent and trivalent forms. The average Mn fractions substituting for Ca, Si, and Al in calcium silicate and aluminate phases were below 3.4 wt%, but up to 7.2 wt% in brownmillerite, Ca₄(Al_1-x-yFe_xMn_y)₄O₁₀, generally with y < 0.25. Most (44–58 wt%) of the Mn was distributed in the RO phase (i.e. divalent metal oxide solid solution), consistent with the thermodynamic modelling results. These findings demonstrate that Mn can be incorporated into several EAF clinker phases, which is an important initial step to understanding and controlling the effects of Mn on EAF clinker properties such as reactivity.

电弧炉炼钢过程中熟料与钢的联产是降低水泥生产碳排放的新途径。然而，钢中的一些元素可能会影响电炉熟料的性能。研究了以普通废钢为原料生产的电炉熟料中Mn的分布。结果表明，这些电炉熟料含有7-8 wt%的氧化锰和二价和三价锰。在硅酸钙相和铝酸钙相中，Mn取代Ca、Si和Al的平均分数低于3.4 wt%，而在褐粒矿Ca4(Al1-x-yFexMny) 40o10中，Mn取代Ca、Si和Al的平均分数高达7.2 wt%，一般为y <； 0.25。大多数Mn （44-58 wt%）分布在RO相（即二价金属氧化物固溶体），与热力学模拟结果一致。这些发现表明，Mn可以掺入多个电炉熟料相中，这是了解和控制Mn对电炉熟料反应性等性能影响的重要一步。

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引用次数: 0