Cement and Concrete Research最新文献_第4页

New insights into dynamic evolution of colloidal network structure during early-age hardening of cementitious materials 胶凝材料早期硬化过程中胶体网络结构动态演化的新认识

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

Cement and Concrete Research

Pub Date : 2025-12-18 DOI: 10.1016/j.cemconres.2025.108120

Hengrui Liu , Kaiyin Zhao , Shipeng Zhang , Hanghua Zhang , Shuangshuang Liu , Lucen Hao , Hongyan Ma , Kamal Khayat , Chi Sun Poon

The evolution of microstructure in cementitious materials during their transition from fluid to solid state plays a critical role in determining their ultimate mechanical strength and overall performance. This hydration stage primarily involves a dynamic densification process occurring within the colloidal network. However, the field of cement-based materials currently lacks a comprehensive theoretical framework and associated parameters capable of effectively characterizing the specific structural regions within this network. In this study, we propose an Improved Particle Linkage (IPL) theory for describing the strength, types, and quantities of particle linkages within colloidal network. The IPL theory classifies the internal network structure into three distinct regions, namely the α_weak, β_strong and γ_inherent. The γ_inherent and β_strong region predominantly influence the strength of the colloidal network at the initial and later hydration stages, respectively, whereas the α_weak region contributes steadily to the network strength across all hydration stages. Furthermore, the progressive intensification of the β_strong region during hydration is identified as the principal driving factor for microstructural evolution, leading to a critical transition point in fresh properties. Additionally, a novel parameter, termed the network hydration index (ξ), to quantitatively characterize the overall degree of hydration within the colloidal network is establishment.

胶凝材料从流体状态向固体状态转变过程中微观结构的演变对其极限力学强度和综合性能起着至关重要的作用。这个水化阶段主要涉及发生在胶体网络内的动态致密化过程。然而，水泥基材料领域目前缺乏能够有效表征该网络中特定结构区域的综合理论框架和相关参数。在这项研究中，我们提出了一种改进的粒子连接（IPL）理论来描述胶体网络中粒子连接的强度、类型和数量。IPL理论将内部网络结构分为三个不同的区域，即α弱、β强和γ固有。γ固有区和β强区分别主要影响水化初期和后期的胶体网络强度，而α弱区则稳定影响所有水化阶段的胶体网络强度。此外，在水化过程中β强区逐渐增强被认为是微观结构演变的主要驱动因素，导致了新鲜性能的关键转变点。此外，建立了一个新的参数，称为网络水化指数（ξ），以定量表征胶体网络内的水化总体程度。

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引用次数: 0

The role of clinker mineralogy in cement properties: An analysis using statistical mixture design 熟料矿物学在水泥性能中的作用：使用统计混合料设计的分析

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

Cement and Concrete Research

Pub Date : 2025-12-17 DOI: 10.1016/j.cemconres.2025.108102

José S. Andrade Neto , Ivo C. Carvalho , Henrique A. Santana , Paulo Matos , Ana Paula Kirchheim

This study applied a statistical mixture design to assess the influence of clinker composition and mineralogy on early hydration and strength. Twenty-one mixtures were prepared using six industrial clinkers with distinct mineralogical characteristics. Hydration was assessed using isothermal calorimetry, X-ray diffraction (XRD) and thermogravimetric analysis (TGA). Compressive strength was measured at 1 and 28 days. The results revealed that alkali content (Na₂Oeq) was the most influential parameter controlling cumulative heat release up to 72 h. Interestingly, no clear correlation was observed between bulk phase content and early strength, emphasizing that mineralogical composition alone is not a reliable predictor of performance. These findings underscore the complexity of hydration mechanisms and highlight the importance of controlling clinker chemistry and mineralogy. Moreover, statistical mixture design proved an effective tool for exploring multivariate interactions governing hydration and strength development.

本研究采用统计混合设计来评估熟料组成和矿物学对早期水化和强度的影响。采用矿物学特征不同的6种工业熟料配制了21种混合料。采用等温量热法、x射线衍射（XRD）和热重分析（TGA）对水合作用进行了评价。在第1天和第28天测量抗压强度。结果表明，碱含量（Na2Oeq）是控制72 h累积放热的最重要参数。有趣的是，体相含量与早期强度之间没有明显的相关性，强调矿物成分本身并不是性能的可靠预测因子。这些发现强调了水化机制的复杂性，并强调了控制熟料化学和矿物学的重要性。此外，统计混合设计被证明是探索控制水化和强度发展的多元相互作用的有效工具。

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引用次数: 0

Quantitative characterization of interfacial enhancement in microfiber-reinforced recycled cementitious composites after carbonation using nanoindentation combined with 4D CT 纳米压痕结合4D CT定量表征微纤维增强再生胶凝复合材料碳化后界面增强

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

Cement and Concrete Research

Pub Date : 2025-12-17 DOI: 10.1016/j.cemconres.2025.108115

Changqing Wang , Yuelan Lu , Zhiming Ma

This study systematically explores the interfacial transition zone (ITZ) strengthening mechanisms in microfiber-reinforced recycled cementitious composites (MF-RCC) under carbonation treatment, primarily through quantitative nanoindentation mapping combined with supportive 4D CT imaging. Nanoindentation was innovatively adopted to quantify ITZ enhancement, revealing significant increases of approximately 42 % in local hardness and 48 % in elastic modulus after carbonation. A statistical deconvolution model was established to interpret the nanoindentation data, clearly showing a shift toward higher hardness and reduced variability (homogeneity improved by approximately 35 %) in the carbonated specimens. Complementary 4D CT characterization validated these findings, indicating a noticeable reduction of porosity by approximately 40 %, thus supporting the mechanical densification of the ITZ. The integrated nanoindentation and statistical modeling results highlight carbonation combined with microfiber reinforcement as an effective approach to optimize interfacial properties and mechanical stability, providing quantitative insights for the sustainable design of recycled cementitious materials.

本研究系统探讨了碳化处理下微纤维增强再生胶凝复合材料（MF-RCC）的界面过渡区（ITZ）强化机制，主要通过定量纳米压痕成像结合支持性4D CT成像。创新地采用纳米压痕来量化ITZ增强，显示碳化后局部硬度显著提高约42%，弹性模量显著提高48%。建立了一个统计反褶积模型来解释纳米压痕数据，清楚地显示碳化样品向更高的硬度和更少的可变性（均匀性提高了约35%）转变。补充4D CT表征证实了这些发现，表明孔隙度显著降低了约40%，从而支持了ITZ的机械致密化。综合纳米压痕和统计建模结果表明，碳化结合超细纤维增强是优化界面性能和机械稳定性的有效方法，为再生胶凝材料的可持续设计提供了定量见解。

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引用次数: 0

Revisiting MgO reactivity: The critical role of mesopores and surface defects of particles 重述氧化镁的反应性：颗粒的介孔和表面缺陷的关键作用

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

Cement and Concrete Research

Pub Date : 2025-12-16 DOI: 10.1016/j.cemconres.2025.108118

Jiaze Wang , Hangjie Zhou , Yufeng Song , Chengzhuo Xie , Cise Unluer , Shaoqin Ruan

The reactivity of magnesia (MgO) is a critical determinant of the performance of magnesia-based cements. While conventional theory correlates MgO reactivity primarily with specific surface area (SSA), this study utilizes a multi-technique approach to reveal a more complex dependency governed by the interplay between pore structure and surface defect density. Through controlled synthesis of MgO from calcinating Mg(OH)₂ at 400, 500, and 600 °C for 2 h, we demonstrate that the sample calcined at 500 °C (S5–2) exhibits the highest reactivity, despite possessing a lower SSA than the 400 °C counterpart. A multi-technique approach, combining TEM, in-situ XRD, BET, LF-NMR, XPS, PL, and ESR analyses, reveals that this enhanced reactivity is strongly correlated with a synergistic combination of a favorable mesoporous architecture (~10–100 nm), hypothesized to facilitate efficient water transport, and a maximized concentration of surface oxygen vacancies, which are believed to promote hydrolysis. This perspective supplements existing theory and provides guidance for designing magnesia cements with stable and reproducible performance, addressing one of the major challenges in this field.

氧化镁（MgO）的反应性是决定镁基水泥性能的关键因素。虽然传统理论将MgO反应性主要与比表面积（SSA）联系起来，但本研究利用多技术方法揭示了由孔隙结构和表面缺陷密度之间的相互作用决定的更复杂的依赖关系。通过对Mg(OH)2在400、500和600℃下煅烧2小时合成MgO的控制，我们发现在500℃（S5-2）下煅烧的样品表现出最高的反应活性，尽管其SSA低于400℃的样品。结合TEM、原位XRD、BET、rf - nmr、XPS、PL和ESR分析的多技术方法表明，这种增强的反应性与有利的介孔结构（~ 10-100 nm）（假设有助于有效的水输送）和最大的表面氧空位浓度（被认为有助于促进水解）的协同作用密切相关。这一观点补充了现有理论，为设计性能稳定、可重复的镁质水泥提供了指导，解决了该领域的主要挑战之一。

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引用次数: 0

Evolution of hydration in cement blends with incorporation of activated low-kaolinite clays: Insights into the preferred aluminum uptake by C-(A)-S-H 掺入活化低高岭石粘土的水泥混合物中水化的演变：C-(A)- s - h对铝的首选吸收的见解

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

Cement and Concrete Research

Pub Date : 2025-12-12 DOI: 10.1016/j.cemconres.2025.108086

Amrita Hazarika , Liming Huang , Joao Figueira , Arezou Babaahmadi

Despite their global abundance, heterogenous clays are often excluded from SCM applications, due to their limited pozzolanicity. This study investigates hydration evolution, particularly aluminum uptake pathways, in statistically designed cement blends incorporating thermo-mechanochemically activated low-kaolinite clays.

Despite kaolinite contents below 40%, a 30% binary blend achieved 110% and 125% of OPC strength at 7 and 56 days, respectively, while reducing total porosity by 42% at 56 days. ²⁹Si NMR indicated an increase in silicate chain length in C-(A)-S-H, correlating with pore structure refinement and strength gain in 56 days of hydration. ²⁷Al NMR revealed a preferential incorporation of aluminum into C-(A)-S-H rather than AFm phases. This behavior is attributed to the lower alumina availability in the system compared to LC3 blends, suggesting that in such environments, C-(A)-S-H becomes the dominant host phase for aluminum. This incorporation pathway reduces the Al availability for carbonate-AFm formation, limiting the synergy typically observed in LC3 systems with added limestone.

尽管非均质粘土在全球范围内丰富，但由于其有限的火山喷发性，它们通常被排除在SCM应用之外。本研究调查了统计设计的水泥混合物中水化演化，特别是铝的吸收途径，这些水泥混合物含有热机械化学活化的低高岭石粘土。尽管高岭石含量低于40%，但30%的二元共混物在第7天和第56天分别达到了OPC强度的110%和125%，同时在第56天将总孔隙度降低了42%。29Si核磁共振表明，C-(A)- s - h中的硅酸盐链长增加，这与水化56 d后孔隙结构的细化和强度的增加有关。27Al核磁共振显示铝优先掺入C-(a)- s - h相，而不是AFm相。这种行为归因于与LC3混合物相比，体系中氧化铝的可用性较低，这表明在这种环境下，C-(A)- s - h成为铝的主要宿主相。这种掺入途径降低了Al对碳酸盐- afm形成的可用性，限制了在添加石灰石的LC3体系中通常观察到的协同作用。

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引用次数: 0

In situ reaction-strengthening of ice-templated porous geopolymers for high anisotropy and robustness 高各向异性和坚固性的冰模板多孔地聚合物的原位反应强化

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

Cement and Concrete Research

Pub Date : 2025-12-11 DOI: 10.1016/j.cemconres.2025.108104

Fangxian Li , Chaofeng Zhang , Qiang Yu , Li Zheng , Jiangxiong Wei , Qijun Yu

Ice-templating enables ordered porous architectures but fails in geopolymers due to suppressed reactions at cryogenic temperatures and water loss during sublimation, yielding fragile scaffolds. We propose an in situ reaction strategy that converts ice from a passive porogen into a controlled-release solvent. By introducing a staged low-temperature polymerization (−5 °C to +5 °C) before sublimation, the gradually melting ice initiates geopolymerization in situ, forming a C-(A)-S-H gel that strengthens pore walls. This approach prevents collapse, ensures faithful ice-template replication, and yields porous geopolymers with compressive strength above 6.5 MPa, far exceeding conventional counterparts (<2 MPa). The materials exhibit pronounced anisotropy (σ_z/σ_y > 3.6) and well-defined lamellar pores. This strategy addresses a key limitation in ice-templating and opens pathways for fabricating high-performance porous materials from water-dependent reactive systems.

冰模板可以实现有序的多孔结构，但由于在低温下抑制反应和升华过程中的水分损失，在地聚合物中失败，产生脆弱的支架。我们提出了一种原位反应策略，将冰从被动多孔介质转化为控释溶剂。通过在升华前引入阶段低温聚合（- 5°C至+5°C），逐渐融化的冰在原位引发地聚合，形成C-(a)- s - h凝胶，增强孔壁。这种方法可以防止坍塌，确保忠实的冰模板复制，并产生抗压强度超过6.5 MPa的多孔地聚合物，远远超过传统的同类产品（2 MPa）。材料具有明显的各向异性（σz/σy > 3.6）和清晰的层状孔隙。该策略解决了冰模板的一个关键限制，并为利用依赖水的反应体系制造高性能多孔材料开辟了途径。

引用次数: 0

Hydration mechanisms in Roman seawater concrete: Archaeological analogue for validation of long-term ageing reactive transport model 罗马海水混凝土的水化机制：验证长期老化反应输运模型的考古模拟

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

Cement and Concrete Research

Pub Date : 2025-12-10 DOI: 10.1016/j.cemconres.2025.108114

Fructueux Jesugnon Sohounme , Mejdi Neji , Nicolas Seigneur , Katia Schörle , Arnaud Coutelas , T. Charpentier , Mélanie Moskura , Cyrielle Jardin , Alexandre Dauzères

Cement-based materials are considered for sealing plugs in deep geological disposal of radioactive waste. Ensuring their long-term durability is critical for safety over millennia. The Roman Concrete (RoC) project uses ancient Roman underwater concretes as analogues to validate reactive transport models for long-term ageing. This study focuses on hydration mechanisms in Roman concrete made with Phlegrean pozzolan, slaked lime, and seawater. Various techniques (XRD, SEM-EDS, NMR, nanoindentation, microtomography, ICP-OES, ion chromatography) were used to characterize hydration products. Casting underwater led to aragonite and brucite layers with a 60 GPa Young's modulus, protecting the concrete from further degradation. In the core, pozzolanic reactions produce C-(A)-S-H phases (Ca/Si = 1.2; Al/Si = 0.2) with a modulus of 12 GPa. HYTEC modeling confirmed the mechanism: incongruent pozzolan dissolution releases ions (K⁺, SiO₄⁴⁻, Al³⁺, Na⁺), promoting C-(A)-S-H formation and portlandite consumption.

在放射性废物的深部地质处置中，考虑使用水泥基材料作为密封塞。确保它们的长期耐用性对几千年的安全至关重要。罗马混凝土（RoC）项目使用古罗马水下混凝土作为模拟物来验证长期老化的反应传输模型。本研究的重点是罗马混凝土的水化机制，由Phlegrean火山灰，熟石灰和海水制成。采用XRD、SEM-EDS、NMR、纳米压痕、微层析成像、ICP-OES、离子色谱等技术对水化产物进行表征。水下浇筑产生了文石和水镁石层，杨氏模量为60 GPa，保护混凝土免受进一步降解。在岩心中，火山灰反应生成C-(A)- s - h相（Ca/Si = 1.2; Al/Si = 0.2），模量为12 GPa。HYTEC模型证实了其机理：不一致的火山灰溶解释放离子（K+, SiO₄4−,Al3+, Na+），促进C-(A)- s - h的形成和硅酸盐的消耗。

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引用次数: 0

Square-root law prediction of chloride penetration rates in stabilized cement pastes 稳定水泥浆中氯离子渗透速率的平方根定律预测

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

Cement and Concrete Research

Pub Date : 2025-12-09 DOI: 10.1016/j.cemconres.2025.108101

Thomas Bernard , William Wilson

The chloride penetration rate in a cementitious system characterizes its ability to resist chloride-induced corrosion. Assessing this property involves determining a diffusion coefficient obtained from diffusion or migration tests, or from models. The evolution of penetration depth can be used to predict the durability of a cementitious system, as it follows a linear relationship with the square root of time, known as the square root law. However, given the many assumptions behind this law, it remains unclear when and how it can be used to predict future penetration depths. This study investigates the applicability of the law for seven binders and shows that it can be used to monitor the evolution of penetration depth before the stabilization of the properties of the specimen, except when glass powder is used. However, predicting future penetration depths is more accurate when both the microstructure and surface content are stable.

氯离子在胶凝体系中的渗透速度表征了其抗氯离子腐蚀的能力。评估这一特性包括确定从扩散或迁移试验或从模型获得的扩散系数。穿透深度的变化可以用来预测胶凝体系的耐久性，因为它与时间的平方根呈线性关系，称为平方根定律。然而，考虑到这一定律背后的许多假设，目前尚不清楚何时以及如何使用它来预测未来的渗透深度。本研究考察了该定律在7种粘结剂中的适用性，结果表明，除了使用玻璃粉外，该定律可用于监测试样性能稳定之前的渗透深度演变。然而，当微观结构和表面含量都稳定时，预测未来的穿透深度更为准确。

引用次数: 0

Examining the pH dependence of Fe behavior in hydrotalcite-group structures 水滑石基团结构中铁行为的pH依赖性研究

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

Cement and Concrete Research

Pub Date : 2025-12-05 DOI: 10.1016/j.cemconres.2025.108097

Jiaxing Ban , Barbara Lothenbach , John L. Provis , George Dan Miron , Zeyu Zhou , Dengquan Wang , Sergey V. Churakov , Bin Ma

Hydrotalcite-group layered double hydroxide (LDH) phases are important in many technical and geological contexts, and in applications ranging from environmental processes to catalysts to cements. This study systematically investigates the roles of Fe in LDH structures across varying pH conditions relevant to concrete environments, combining laboratory-based characterization, synchrotron-based techniques, and thermodynamic modeling. Elevated pH enhances Fe incorporation into the LDH phase, while suppressing ferrihydrite formation. At pH > 11, partial LDH dissolution is observed. Thermodynamic modeling and diffractometry reveal the transformation mechanism: control of the initial pH increases promotes Al(III) and Fe(III) uptake into LDH structures, while further alkalinization (pH > 11) triggers selective Al(III) dissolution, thereby increasing the M²⁺/M³⁺ ratio and altering unit cell parameters. These findings elucidate the dynamics between Fe(III) incorporation in LDH and ferrihydrite precipitation, governed by pH-dependent solubility and charge-balance constraints.

水滑石-组层状双氢氧化物（LDH）相在许多技术和地质背景下，以及从环境过程到催化剂到水泥的应用中都很重要。本研究结合基于实验室的表征、基于同步加速器的技术和热力学建模，系统地研究了铁在与混凝土环境相关的不同pH条件下在LDH结构中的作用。pH值升高会促进铁与LDH相结合，同时抑制水合铁的形成。在pH >； 11下，LDH部分溶解。热力学模型和衍射分析揭示了转化机制：控制初始pH的增加促进Al（III）和Fe（III）被LDH结构吸收，而进一步的碱化（pH > 11）触发Al（III）选择性溶解，从而增加M2+/M3+比率并改变单元胞参数。这些发现阐明了铁（III）掺入LDH和水合铁沉淀之间的动力学，受ph依赖性溶解度和电荷平衡约束。

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引用次数: 0

Multi-scale mechanical behaviors of ultra-high performance fiber-reinforced concrete influenced by ultra-fine mineral additives: A hierarchical perspective on toughness gain modulation 超细矿物添加剂对超高性能纤维增强混凝土多尺度力学行为的影响：韧性增益调节的分层视角

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

Cement and Concrete Research

Pub Date : 2025-12-03 DOI: 10.1016/j.cemconres.2025.108099

Qiaomu Zheng , En-Hua Yang , Chen Li , Qiang Ren , Hongen Zhang , Wenting Li , Sifan Zhang , Zhengwu Jiang

Enhancing the toughness gain of ultra-high performance fiber-reinforced concrete (UHPFRC) through fundamental unit (e.g., nanostructure) optimization remains a challenge. This work explores the multi-scale mechanical behaviors of UHPFRC under four-point flexural loads, incorporating silica fume (SF) and ultra-fine fly ash (UFFA) as the ultra-fine mineral additives. SF and UFFA promote the formation of C(A)SH with high Si/Ca and Al/Ca ratio, altering the structural characteristics of both cement matrix and fiber-matrix interface. At the nanoscale, SF enhances the C(A)SH modulus through higher cohesion force, while UFFA elevates its friction coefficient; although both additives decrease C(A)SH hardness by reduced intrinsic modulus, their synergism improves C(A)SH stiffness. At the micro/macroscale, the stiffness of cement matrix and modulus of fiber-matrix interface dominate the strain-hardening behavior before fiber debonding, whereas the stiffness and friction coefficient of interface control the strain-softening process during fiber pulling-out. These insights highlight the hierarchical pathway to toughness modulation in UHPFRC.

通过优化基本单元（如纳米结构）来提高超高性能纤维增强混凝土（UHPFRC）的韧性增益仍然是一个挑战。以硅灰（SF）和超细粉煤灰（UFFA）为超细矿物添加剂，研究了UHPFRC在四点弯曲载荷下的多尺度力学行为。SF和UFFA促进了高Si/Ca和Al/Ca比的C(A)SH的形成，改变了水泥基体和纤维-基体界面的结构特征。在纳米尺度上，SF通过提高黏聚力提高C(A)SH模量，UFFA通过提高摩擦系数提高C(A)SH模量；虽然两种添加剂都通过降低固有模量来降低C(A)SH硬度，但它们的协同作用提高了C(A)SH刚度。在微观和宏观尺度上，水泥基体刚度和纤维-基体界面模量主导着纤维脱粘前的应变硬化行为，而界面刚度和摩擦系数控制着纤维脱粘过程中的应变软化过程。这些见解强调了UHPFRC韧性调节的分层途径。

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引用次数: 0