Cement & concrete composites最新文献

Hydration-driven microstructural evolution mechanism of ternary waste-based geopolymer materials 三元废基地聚合物材料水化驱动的微观结构演化机制

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

Cement & concrete composites

Pub Date : 2026-01-29 DOI: 10.1016/j.cemconcomp.2026.106502

Qingbo Liu , Junchen Xiang , Zhengyu Ma , Linjie Liu , Biqi Ren , Jingping Qiu

Traditional alkali-activated solid-waste-based cementitious materials predominantly rely on strong industrial alkali activators, posing significant corrosion risks that cannot be overlooked and making long-term stability difficult to guarantee. In order to reveal the hydration-driven microstructure evolution mechanism behind the performance evolution of multi-source solid-waste-based cementitious materials, a micro-macro multiscale analysis framework was employed to elucidate the intrinsic connections between the microstructure characteristics and micromechanical behavior of reaction products and the development of hydration activity and long-term strength. The evolution of gel nanostructures and the molecular changes affecting overall performance are emphasized in this study. Coal gasification slag (CGS), municipal solid waste incineration fly ash (MSWI FA), and calcium carbide residue (CCR) were successfully utilized in preparing engineered geopolymer composites (EGC) without clinker or admixtures. The Cl⁻ introduced by MSWI FA and the OH⁻ ions generated by CCR jointly regulate the hydration reaction pathway of CGS, providing a new activation pathway. The hydration kinetic, microstructural evolution, and mechanical property development of the mortar were investigated through characterization experiments. The results show that the mortar with a 10 wt% substitution rate of MSWI FA reached a compressive strength of 3.53 MPa at 90 days. The hydration reaction kinetics and structural evolution followed a compatible developmental pathway. The evolution of the Si−O tetrahedral structure and the involvement of Cl⁻ in the hydration process altered the gel structure, contributing to the formation of a denser microstructure. This enhancement in mechanical properties was accompanied by a reduction of over 70 % in carbon emissions. These results advance the technological development of utilizing CGS and MSWI FA as cementitious materials for waste reuse, providing scientific importance in carbon reduction and waste management.

传统碱活化固废基胶凝材料主要依靠强工业碱活化剂，存在不可忽视的重大腐蚀风险，长期稳定性难以保证。为了揭示多源固体废物基胶凝材料性能演化背后的水化驱动微观结构演化机制，采用微观-宏观多尺度分析框架，阐明反应产物的微观结构特征和微观力学行为与水化活性和长期强度发展之间的内在联系。凝胶纳米结构的演变和影响整体性能的分子变化是本研究的重点。利用煤气化渣（CGS）、城市生活垃圾焚烧粉煤灰（MSWI FA）和电石渣（CCR）成功制备了不含熟料和外加剂的工程地聚合物复合材料（EGC）。MSWI FA引入的Cl−和CCR产生的OH−离子共同调控了CGS的水化反应途径，提供了一种新的活化途径。通过表征实验研究了砂浆的水化动力学、微观结构演变和力学性能发展。结果表明：MSWI FA替代率为10 wt%的砂浆，90 d抗压强度为3.53 MPa；水化反应动力学和结构演化遵循相容的发展路径。Si - O四面体结构的演化和Cl -在水化过程中的参与改变了凝胶结构，有助于形成更致密的微观结构。机械性能的提高伴随着碳排放量减少了70%以上。这些研究结果推动了CGS和MSWI FA作为胶凝材料进行废弃物回用的技术发展，对碳减排和废弃物管理具有科学意义。

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引用次数: 0

The coupling effect of viscosity modifying agents and printing process on the air-void structure formation of 3D printed air-entrained concrete 黏度改性剂与打印工艺对3D打印掺气混凝土气孔结构形成的耦合效应

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

Cement & concrete composites

Pub Date : 2026-01-23 DOI: 10.1016/j.cemconcomp.2026.106497

Yuyang Kang , Cheng Yu , Zedi Zhang , Lutao Jia , Xianggang Wang , Nemkumar Banthia , Yamei Zhang , Zijian Jia

3D printed concrete (3DPC) holds significant potential for applications in extreme environments. Air-entraining agents (AEAs) can enhance the frost resistance of concrete in cold regions by introducing uniformly distributed small air-voids. However, in 3DPC, the use of viscosity-modifying agents (VMAs) and the unique printing process may adversely affect the characteristics of entrained air-voids. This study employs X-ray computed tomography (X-CT) to quantitatively characterize the evolution of air-void structures in AEA-modified 3DPC containing different VMAs across three critical manufacturing stages: before-printing, in-printing-nozzle and after-printing. The results reveal that the shear action of the screw rod effectively refines the air-void size distribution while increasing overall air-void volume fraction. Hydroxypropyl methyl cellulose (HPMC) effectively stabilizes small bubbles (<500 μm) during before-printing stage, increasing the air-voids count via a protective film that prevents rupture. Conversely, attapulgite leaves small bubbles vulnerable to break. However, during in-printing-nozzle and after-printing stage, attapulgite better protects large bubbles (>1000 μm), maintaining their shape against shear and elongation forces with a stable shell, while HPMC offers little protection, leading to more significant elongated bubble shapes. This study provides an experimental basis for regulating air-void structure in 3D printed air-entrained concrete from the perspective of materials selection and printing processes control.

3D打印混凝土（3DPC）在极端环境中具有巨大的应用潜力。在寒冷地区，引气剂通过引入均匀分布的小空隙来提高混凝土的抗冻性。然而，在3DPC中，粘度改性剂（vma）的使用和独特的打印工艺可能会对夹带空隙的特性产生不利影响。本研究采用x射线计算机断层扫描（X-CT）定量表征了含有不同vma的aea改性3DPC在打印前、打印喷嘴中和打印后三个关键制造阶段的气孔结构演变。结果表明，螺杆的剪切作用有效地细化了气孔尺寸分布，提高了整体气孔体积分数；羟丙基甲基纤维素（HPMC）在打印前阶段有效地稳定小气泡（<500 μm），通过保护膜防止破裂，增加空隙数。相反，凹凸棒石会留下容易破裂的小气泡。然而，在打印喷嘴内和打印后阶段，凹凸棒土可以更好地保护大气泡（>1000 μm），并以稳定的外壳保持其剪切和伸长力的形状，而HPMC的保护作用较小，导致气泡形状更明显拉长。本研究从材料选择和打印工艺控制的角度为3D打印充气混凝土的气孔结构调节提供了实验依据。

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引用次数: 0

Microstructural evolution of limestone calcined clay cement (LC3) paste: Insights from hydration to drying using 1H-NMR relaxometry 石灰石煅烧粘土水泥（LC3）膏体的微观结构演化：利用1H-NMR弛豫仪从水化到干燥的见解

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

Cement & concrete composites

Pub Date : 2026-01-22 DOI: 10.1016/j.cemconcomp.2026.106496

Zhenli Yang, Luge Cheng, Ryo Kurihara, Ippei Maruyama

Understanding the microstructure change during drying in limestone calcined clay cement (LC

^{3}

) is crucial for promoting low-clinker cementitious materials and reducing the environmental impact of cement production. Building on microstructural change during hydration, this study investigates the pore structure and phase change in LC

^{3}

and its influence on macroscopic shrinkage. Composition analysis of the hydrates was conducted using X-ray diffraction and energy-dispersive X-ray spectroscopy. Additionally, proton nuclear magnetic resonance relaxometry was used to determine pore structure. Microscopically, the reacted metakaolin residues yield NMR signals that fall within the same

T_{2}

range as those typically assigned to interhydrate pores within calcium alumino-silicate hydrate (C–A–S–H), yet they originate from different structural domains. The low Ca/(Al+Si) ratio in LC

^{3}

results in sparsely packed C–A–S–H with interlayer spaces that remain structurally stable and retain water strongly during drying, showing little change even under low relative humidity. During drying, water is mainly held in and released from gel, interhydrate, and capillary pores. LC

^{3}

exhibits significantly lower shrinkage than OPC, which is attributed, based on the C–A–S–H structural model, to its lower Ca concentration and the resulting interlayer structure that remains stable and water-retentive at low humidity.

了解石灰石煅烧粘土水泥（LC33）在干燥过程中的微观结构变化，对于推广低熟料胶凝材料和减少水泥生产对环境的影响至关重要。本研究以水化过程中的微观结构变化为基础，研究LC33的孔隙结构和相变化及其对宏观收缩的影响。利用x射线衍射和能量色散x射线光谱对水合物进行了成分分析。此外，质子核磁共振弛豫仪测定孔隙结构。在显微镜下，反应后的偏高岭土残留物产生的核磁共振信号与钙铝硅酸盐水合物（C-A-S-H）中通常分配给水合物间孔隙的核磁共振信号处于相同的T2T2范围内，但它们来自不同的结构域。LC33的低Ca/(Al+Si)比导致C-A-S-H结构稀疏，层间空间在干燥过程中保持结构稳定和强保水性，即使在低相对湿度下也几乎没有变化。在干燥过程中，水主要从凝胶、水合物和毛细孔中被保留和释放。根据C-A-S-H结构模型，LC33的收缩率明显低于OPC，这是由于LC33的Ca浓度较低，导致其层间结构在低湿度下保持稳定和保水性。

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引用次数: 0

Retention mechanisms of stable- and radioactive- Cs and Sr in geopolymer materials: Insights into gel structural evolution and leaching behavior 稳定和放射性铯和锶在地聚合物材料中的保留机制：对凝胶结构演化和浸出行为的见解

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

Cement & concrete composites

Pub Date : 2026-01-22 DOI: 10.1016/j.cemconcomp.2026.106490

Guiyan Xiong , Andrew B. Cundy , Xiaolu Guo

Geopolymers are potentially useful materials for radioactive wastes stabilization or immobilization. This study explores the retention mechanisms of stable- and radioactive-Cs and Sr in fly ash (FA)/ground granulated blast furnace slag (GGBS) blended geopolymer materials by examining the evolution of phases evolution and gel structures during geopolymer curing and subsequent element/radionuclide leaching behavior in Milli Q water (MW) and simulated Sellafield underground water (UW). Results show that Cs⁺ incorporation altered gel structures, while Sr²⁺ disrupted the geopolymerization process and generated SrCO₃. Diffusion and dissolution mechanisms governed the leaching of Cs⁺ from the geopolymer, with geopolymer undergoing gel structural transformations during leaching in both MW and UW, while Cs ⁺ may facilitate Al release in the UW. Diffusion mechanism primarily drove the leaching of Sr²⁺ from geopolymer into Milli Q water, involving localized structural reorganization. Leaching in the UW probably involved gel transformation/reorganization and SrCO₃ dissolution. Cs was more mobile than Sr regardless of whether stable or radioactive nuclides were applied, and compared with conventional cement stabilisers, geopolymer exhibited better immobilization. The leaching results and immobilization mechanisms of geopolymer for stable and radioactive nuclides were not always completely aligned, warranting further direct investigation using radioactive nuclides. This study provides a perspective on product evolution both during geopolymer incorporation and subsequent leaching of Cs and Sr, and highlights the potential of geopolymer materials to effectively stabilize and immobilize Cs and Sr-containing nuclear wastes.

地聚合物是稳定或固定放射性废物的潜在有用材料。本研究通过考察地聚合物固化过程中相演化和凝胶结构的演变，以及随后在Milli Q水（MW）和模拟Sellafield地下水（UW）中的元素/放射性核素浸出行为，探讨了稳定型和放射性铯和锶在粉煤灰(FA)/磨粒高炉渣（GGBS）混合地聚合物材料中的保留机制。结果表明，Cs+的掺入改变了凝胶结构，而Sr2+破坏了地聚合过程，生成了SrCO3。Cs+从地聚合物中浸出主要受扩散和溶解机制的控制，在MW和UW浸出过程中，地聚合物都发生了凝胶结构转变，而Cs+可能促进Al在UW中的释放。扩散机制主要驱动Sr2+从地聚合物中浸出到Milli Q水中，涉及局部结构重组。UW的浸出可能涉及凝胶转化/重组和SrCO3溶解。无论使用稳定核素还是放射性核素，Cs都比Sr具有更强的可移动性，并且与常规水泥稳定剂相比，地聚合物具有更好的固定性。地质聚合物对稳定核素和放射性核素的浸出结果和固定机制并不总是完全一致，需要进一步使用放射性核素进行直接研究。本研究提供了在地聚合物掺入和随后的Cs和Sr浸出过程中产物演变的视角，并强调了地聚合物材料在有效稳定和固定含Cs和Sr的核废料方面的潜力。

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引用次数: 0

Synergistic effects of triethanolamine and nano-SiO2 on the hydration and hardening properties of Limestone calcined clay cement 三乙醇胺和纳米sio2对石灰石煅烧粘土水泥水化硬化性能的协同作用

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

Cement & concrete composites

Pub Date : 2026-01-21 DOI: 10.1016/j.cemconcomp.2026.106492

Mingqing Liu , Zhonghao Niu , Xiangming Zhou , Pengkun Hou , Ran Hai , Shuang Liang , Yuzhou Sun

This study investigates the synergistic effects of triethanolamine (TEA) and nano-SiO₂ (NS) on the hydration, mechanical properties and microstructure of Limestone Calcined Clay Cement (LC³). Isothermal calorimetry results reveal that NS primarily enhances the hydration degree of the silicate phase, whereas TEA preferentially accelerates aluminate hydration through Al³⁺ complexation and surface adsorption, which modifies ion availability and delays C-S-H nucleation, thereby regulating the timing of the silicate peak. Both NS and TEA can increase the intensity of the aluminate peak, while their combination produces an even stronger synergistic effect. TEA consistently contributes to LC³ strength development at all ages, while NS mainly improves early-age strength. The synergistic effect of NS and TEA is more pronounced than either additive alone, with the LC³-3NS-0.2 %TEA (with 3 % NS and 0.2 % TEA) blend exhibiting the best performance across all ages. TEA leads to a greater consumption of CH compared to NS, while NS-TEA blends yield a higher volume of hydrates, including C-(A)-S-H gel, AFm, and AFt phases. Moreover, TEA primarily influences pore size distribution rather than total porosity, shifting larger, more harmful pores into smaller, less detrimental ones. The NS-TEA synergistic blend achieves the most favourable pore structure, characterised by the lowest content of harmful pores (>100 nm) and the highest proportion of fine pores (4.5–50 nm and <4.5 nm).

研究了三乙醇胺（TEA）和纳米sio2 （NS）对石灰石煅烧粘土水泥（LC3）水化、力学性能和微观结构的协同作用。等温量热分析结果表明，NS主要增强硅酸盐相的水化程度，而TEA则通过Al3+络合和表面吸附优先加速铝酸盐的水化，从而改变了离子的可用性，延缓了C-S-H成核，从而调节了硅酸盐峰的时间。NS和TEA均能增加铝酸盐峰的强度，两者的联合产生更强的协同效应。TEA对各年龄段LC3强度的发展有一致的促进作用，而NS主要对早期强度有促进作用。NS和TEA的协同作用比单独添加任何一种添加剂都更明显，lc3 - 3ns - 0.2% TEA（含有3% NS和0.2% TEA）的混合料在各年龄段表现最佳。与NS相比，TEA导致更多的CH消耗，而NS-TEA混合物产生更大体积的水合物，包括C-(a)- s - h凝胶，AFm和AFt相。此外，TEA主要影响孔径分布，而不是总孔隙率，将较大、更有害的孔隙转移到较小、更无害的孔隙中。NS-TEA增效共混物孔隙结构最优，有害孔隙（100 nm）含量最低，细孔（4.5 ~ 50 nm和4.5 nm）比例最高。

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引用次数: 0

5-1-7 phase regulation and performance enhancement of magnesium oxysulfate cement: Research progress and engineering perspectives 硫酸镁水泥的物相调控与性能提升：研究进展与工程展望

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

Cement & concrete composites

Pub Date : 2026-01-21 DOI: 10.1016/j.cemconcomp.2026.106495

Yanling Guo , Bin Li , Xiangrui Meng , Zhenzhen Liu , Yao Xiao , Bing Chen

Magnesium oxysulfate cement (MOSC), as a green cementitious material, has gradually attracted widespread attention. Its advantages mainly stem from low carbon emissions, excellent high-temperature resistance, and lightweight properties. However, the performance of MOSC fundamentally depends on the formation and stability of a specific crystalline phase, especially the 5-1-7 phase (5Mg(OH)₂·MgSO₄·7H₂O). This key crystalline phase not only determines the material's mechanical properties but is also crucial for improving its insufficient water resistance and optimizing its functional applications. However, few reviews systematically summarize the application of the 5-1-7 phase in this important field of modified MOSC. In this review, we comprehensively summarize the research progress on the hydration process and representative crystal structures of MOSC in the MgO–MgSO₄–H₂O system, focusing on the formation mechanism of the 5-1-7 phase and exploring its significant impact on the mechanical strength, high-temperature resistance, and lightweight applications of MOSC. This paper also systematically reviews existing modification strategies, with a particular focus on analyzing the mechanisms by which admixtures and fillers affect the formation of the 5-1-7 phase and improve the overall material properties. Furthermore, we summarize the application progress of MOSC across multiple engineering scenarios and systematically evaluate the pivotal role of 5-1-7 phase regulation in engineering applications. Finally, this paper identifies key scientific issues that urgently need to be addressed in current research and proposes future research directions, providing necessary theoretical support for accelerating its application in the engineering field.

硫酸氧镁水泥作为一种绿色胶凝材料，逐渐受到广泛的关注。其优点主要源于低碳排放、优异的耐高温性能和轻质性能。然而，MOSC的性能从根本上取决于特定晶相的形成和稳定性，特别是5-1-7相（5Mg(OH)2·MgSO4·7H2O）。这种关键的晶相不仅决定了材料的机械性能，而且对于改善其不足的耐水性和优化其功能应用也至关重要。然而，很少有文献系统地总结5-1-7相在改性MOSC这一重要领域的应用。本文综合总结了MgO-MgSO4-H2O体系中MOSC的水化过程和代表性晶体结构的研究进展，重点探讨了5-1-7相的形成机理，并探讨了其对MOSC机械强度、耐高温性能和轻量化应用的重要影响。本文还系统地回顾了现有的改性策略，重点分析了外加剂和填料影响5-1-7相形成和改善材料整体性能的机制。在此基础上，总结了多工程场景下MOSC的应用进展，系统评价了5-1-7相位调节在工程应用中的关键作用。最后，本文明确了当前研究中急需解决的关键科学问题，并提出了未来的研究方向，为加快其在工程领域的应用提供了必要的理论支持。

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引用次数: 0

Influence of matrix strengthening, interface enhancement and fiber orientation on the flexural behavior and damage evolution of UHPC 基体增强、界面增强和纤维取向对UHPC弯曲行为和损伤演化的影响

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

Cement & concrete composites

Pub Date : 2026-01-21 DOI: 10.1016/j.cemconcomp.2026.106494

Junjie Du , Fengling Zhang , Huigang Xiao , Leong Hien Poh

The damage evolution of performance-enhanced ultra-high-performance concrete (UHPC) has always been a research focus. Herein, a combination of acoustic emission (AE) and digital image correlation (DIC) is adopted to systematically investigate the effects of interface enhancement, matrix strengthening and fiber orientation on the damage temporal evolution of UHPC. Nano-SiO₂ coated steel fibers and high dosage of nano-SiO₂ are adopted to achieve interface enhancement and matrix strengthening, respectively. The results indicate that interface enhancement, matrix strengthening and fiber orientation can effectively delay the unstable propagation of the main crack in UHPC, and the failure initiation time of UHPC is delayed by more than 20 s. Different from the single crack failure of matrix-strengthened UHPC, interface-enhanced UHPC is more prone to multi-crack failure. The principal component analysis results indicate that the acoustic energy of matrix cracking in interface-enhanced UHPC increases by more than 200 %, significantly improving the strength utilization of the matrix, and this tendency is promoted after orientation. The high dosage of nano-SiO₂ simultaneously strengthened both the interface and the matrix. Compared with unreinforced UHPC, the failure initiation time of interface-enhanced and matrix-strengthened UHPC was delayed by 28s and 61s, respectively, and the failure duration increases by 19s and 102s, respectively. By combining the load-displacement curve and AE characteristic parameters, the boundary values of the historic index (HI) and severity (S_r) are proposed, which has potential significance to provide safety warning for UHPC structures based on AE technology.

高性能混凝土（UHPC）的损伤演化一直是研究的热点。本文采用声发射（AE）和数字图像相关（DIC）相结合的方法，系统地研究了界面增强、基体增强和纤维取向对UHPC损伤时间演化的影响。采用纳米sio2包覆钢纤维和高剂量的纳米sio2分别实现界面增强和基体强化。结果表明：界面增强、基体强化和纤维取向能有效延缓UHPC主裂纹的不稳定扩展，使UHPC的破坏起裂时间延迟20 s以上；与基体增强UHPC的单裂纹破坏不同，界面增强UHPC更容易出现多裂纹破坏。主成分分析结果表明，界面增强UHPC的基体开裂声能提高200%以上，显著提高了基体的强度利用率，定向后这种趋势得到促进。高剂量的纳米sio2同时强化了界面和基体。与未增强UHPC相比，接口增强和基体增强UHPC的失效起始时间分别延迟了28秒和61秒，失效持续时间分别延长了19秒和102秒。结合荷载-位移曲线和声发射特征参数，提出了历史指数（HI）和严重程度（Sr）的边界值，对基于声发射技术的超高性能混凝土结构安全预警具有潜在意义。

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引用次数: 0

CO2-induced rheological response of cement paste driven by the evolution of interparticle interactions 颗粒间相互作用演化驱动的co2诱导水泥浆体流变响应

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

Cement & concrete composites

Pub Date : 2026-01-20 DOI: 10.1016/j.cemconcomp.2026.106486

Chunjin Li , Xiaodi Dai , Zhiyuan Liu , Xianqing Xia , Qiang Ren , Zhengwu Jiang

Growing interest in CO₂ injection during mixing stems from its coupled impacts on early-age properties and CO₂ uptake. Here we elucidate the rheological response by quantifying how interparticle interactions govern this effect. We combined rheological measurements with zeta potential analysis, atomic force microscopy (AFM) pull-off force mapping, inductively coupled plasma optical emission spectrometry (ICP-OES) and pH characterization of pore solution, thermogravimetric analysis (TGA), transmission electron microscopy (TEM), low-field proton nuclear magnetic resonance (¹H NMR), and interparticle-force simulations using Hamaker 2.2. Results show that CO₂ injection decreases particle zeta potential by 22.5 %–64.7 % via carbonate precipitation and ionic enrichment, weakening electrostatic repulsion while strengthening van der Waals attraction and promoting carbonate bridging. Consequently, a rigid flocculated network forms, raising yield stress (∼41.3 % under pure CO₂ injection) and apparent viscosity. Under shear, the reduced energy barrier facilitates bond rupture and agglomerate breakdown, resulting in lower plastic viscosity. In parallel, early hydration is retarded, slowing structural build-up, illustrating 37.5 % reduction in storage modulus. These findings establish a mechanistic link between early-age carbonation, interparticle forces, and macroscopic rheology, and provide guidance for optimizing CO₂ injection to balance flowability and CO₂ uptake in low-carbon cementitious materials.

对混合过程中二氧化碳注入的兴趣越来越大，因为它对早期特性和二氧化碳吸收的耦合影响。在这里，我们通过量化粒子间相互作用如何控制这种效应来阐明流变响应。我们结合了流变学测量和zeta电位分析、原子力显微镜（AFM）拉脱力图、电感耦合等离子体光学发射光谱（ICP-OES）和孔隙溶液的pH表征、热重分析（TGA）、透射电子显微镜（TEM）、低场质子核磁共振（1H NMR）以及使用Hamaker 2.2进行粒子间力模拟。结果表明，CO2注入通过碳酸盐沉淀和离子富集使粒子zeta电位降低22.5% ~ 64.7%，减弱静电斥力，增强范德华引力，促进碳酸盐桥接。因此，形成刚性絮凝网络，提高屈服应力（在纯CO2注入下约41.3%）和表观粘度。剪切作用下，能垒降低，有利于粘结断裂和团聚体破碎，导致塑性粘度降低。同时，早期水化被延缓，减缓了结构的积聚，表明存储模量降低了37.5%。这些发现建立了早期碳化作用、颗粒间作用力和宏观流变性之间的机制联系，并为优化二氧化碳注入以平衡低碳胶凝材料的流动性和二氧化碳吸收率提供了指导。

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引用次数: 0

Polydopamine-assisted carbon black grafting on natural fine aggregates for highly conductive and piezoresistive cement mortar 聚多巴胺辅助炭黑在天然细骨料上接枝制备高导电压阻水泥砂浆

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

Cement & concrete composites

Pub Date : 2026-01-19 DOI: 10.1016/j.cemconcomp.2026.106493

Jun Yang , Zhen Zhang , Jingchen Leng , Jianting Zhou , Xiuman Wang , Zhongya Zhang , Yang Zou , Le Teng , Soroush Mahjoubi , Jiang Du , Weina Meng

The inherent electrical insulation of cementitious composites fundamentally limits their application in smart infrastructure requiring self-sensing capabilities. Direct dispersion of conductive nanofillers, while improving conductivity, easily triggers nanoparticle agglomeration and internal defects, causing significant mechanical degradation. Conventional surface modification techniques on aggregates are energy-intensive or environmentally hazardous, posing barriers to scalable implementation. To overcome dual challenges, we hypothesize a mussel-mimetic interfacial engineering strategy, leveraging dopamine's spontaneous polymerization into a polydopamine (PDA) adhesive layer, anchors carbon black (CB) onto fine aggregates (CB + PDA@FA) for the conductive aggregate's fabrication, which is simple, energy-efficient, and environmentally friendly. The optimized cement mortar (M-0.4CF + CFA) containing CB + PDA@FA and carbon fibers achieves an electrical resistivity of 1.8 × 10³ Ω cm (five orders of magnitude reduction), while preserving compressive and flexural strengths. This is attributed to that the utilization of CB + PDA@FA did not significantly compromise the pore structure and ITZ of cement mortar. Moreover, M-0.4CF + CFA exhibits exceptional piezoresistive sensitivity under cyclic loading, attaining a gauge factor of ∼98 and a fractional resistivity change up to 5.2 %. Density functional theory calculations validated the PDA interlayer amplifies the chemisorption energy between CB and aggregates, stabilizing the robust conductive network. This work potentially resolves the conductivity-mechanical property conflict in cementitious materials which provide new insights into bio-inspired interfacial design for smart composites, paving the way for energy-efficient, self-sensing infrastructure systems.

胶凝复合材料固有的电绝缘性从根本上限制了其在需要自感知能力的智能基础设施中的应用。导电纳米填料的直接分散在提高导电性的同时，容易引发纳米颗粒团聚和内部缺陷，造成明显的机械退化。传统的骨料表面改性技术是能源密集型或环境危险的，对大规模实施构成障碍。为了克服双重挑战，我们假设了一种模拟贻贝的界面工程策略，利用多巴胺的自发聚合成聚多巴胺（PDA）粘合层，将炭黑（CB）锚定在细骨料（CB+PDA@FA）上，用于导电骨料的制造，这是一种简单，节能且环保的方法。优化后含有CB+PDA@FA和碳纤维的水泥砂浆（M-0.4CF+CFA）的电阻率为1.8×103 Ω·cm（降低了5个数量级），同时保持了抗压和抗弯强度。这是由于CB+PDA@FA的使用对水泥砂浆的孔隙结构和ITZ没有明显的影响。此外，M-0.4CF+CFA在循环加载下表现出优异的压阻灵敏度，测量系数达到~ 98，分数电阻率变化高达5.2%。密度泛函理论计算验证了PDA中间层放大了CB和聚集体之间的化学吸附能，稳定了稳健的导电网络。这项工作潜在地解决了胶凝材料的电导率-力学性能冲突，为智能复合材料的仿生界面设计提供了新的见解，为节能、自传感基础设施系统铺平了道路。

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引用次数: 0

Fiber–textile hybrid reinforcement on pseudo-ductile behavior of ultra-high-performance concrete 纤维-纺织品混合配筋对高性能混凝土伪延性的影响

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

Cement & concrete composites

Pub Date : 2026-01-18 DOI: 10.1016/j.cemconcomp.2026.106484

Hyun-Soo Youm, Jang-Woon Baek, Young Hak Lee, Dae-Jin Kim

Textile-reinforced ultra-high-performance concrete (TR-UHPC) offers great potential for thin-walled structures that meet both serviceability and structural demands. However, the engineering of fiber–textile hybrid reinforcement to simultaneously enhance the strength and pseudo-ductility has rarely been explored. This study reports on uniaxial tensile tests of 60 TR-UHPC tie specimens reinforced with varying amounts of steel fibers (0 %, 1 %, or 2 % by volume) and textile fabrics (0, 1, or 2 layers of carbon or AR-glass textiles). Key mechanical properties, including the crack spacing, cracking stress, tensile strength, strain capacity, and strain energy density (g-value), were examined to assess the overall composite efficiency. Most test results agreed with the expectations based on domain knowledge and complementary material/interface characterizations. However, incorporating short fibers beyond an optimal dosage unexpectedly reduced the ductility, thereby offsetting composite efficiency. A simple theoretical analysis linking crack spacing and strain capacity attributed the reduced ductility to premature damage localization at a single crack, initiated by local deficiencies in short fiber spatial features. These findings offer practical implications for optimizing reinforcement hybridization and advance the development of low-carbon, high-performance building materials.

纺织增强高性能混凝土（TR-UHPC）为薄壁结构提供了巨大的潜力，同时满足了使用性能和结构要求。然而，同时提高强度和伪延性的纤维-纺织品混合增强工程很少进行探索。本研究报告了用不同数量的钢纤维（按体积计为0%、1%或2%）和纺织织物（0层、1层或2层碳或ar玻璃纺织品）增强的60个TR-UHPC tie试件的单轴拉伸试验。研究了裂纹间距、裂纹应力、抗拉强度、应变能力和应变能密度（g值）等关键力学性能，以评估复合材料的整体效率。大多数测试结果符合基于领域知识和互补材料/界面特征的期望。然而，超过最佳用量的短纤维出乎意料地降低了延展性，从而抵消了复合材料的效率。将裂纹间距和应变能力联系起来的简单理论分析将延性降低归因于单个裂纹的过早损伤局部化，这是由短纤维空间特征的局部缺陷引起的。这些发现为优化钢筋杂交和推进低碳、高性能建筑材料的发展提供了实际意义。

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引用次数: 0