Cement & concrete composites最新文献_第2页

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

Improved corrosion resistance of steel in mortar incorporating molybdate-loaded HNTs: Microstructural refinement and protective film formation 加入钼酸盐负载HNTs的砂浆中提高钢的耐腐蚀性：微观结构的细化和保护膜的形成

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

Cement & concrete composites

Pub Date : 2026-01-17 DOI: 10.1016/j.cemconcomp.2026.106491

Yongqi Liu , Jinjie Shi

To mitigate the adverse impacts of traditional corrosion inhibitors on concrete performance, recent research has focused on using nano-containers for encapsulating inhibitors. However, previous studies have primarily utilized simulated concrete pore solutions, without adequately addressing the effects of nano-containers on the concrete matrix or the actual service environment on inhibitor efficiency. To bridge these gaps, this study aims to explore the feasibility and applicability of halloysite nanotubes (HNTs), as the nano-containers for encapsulating molybdate ions, to enhance the corrosion resistance of steel embedded in mortar. Accordingly, a molybdate-loaded halloysite nanotube (HNT@MO) was successfully synthesized and incorporated into mortar. The results revealed that the release of molybdate ions from HNTs could promote the formation of a protective oxide film on the steel surface and suppress the corrosion process caused by chloride attack. In addition, the incorporation of HNT@MO enhanced the mechanical properties of mortar by refining microstructure and reducing porosity. Accordingly, this synergistic inhibition effect of HNT@MO improved the corrosion resistance of steel in mortar against chloride-induced corrosion.

为了减轻传统缓蚀剂对混凝土性能的不利影响，最近的研究重点是使用纳米容器封装缓蚀剂。然而，之前的研究主要是利用模拟的混凝土孔隙溶液，没有充分解决纳米容器对混凝土基体或实际使用环境对抑制剂效率的影响。为了弥补这些空白，本研究旨在探索高岭土纳米管（HNTs）作为包封钼酸盐离子的纳米容器，提高砂浆中预埋钢的耐腐蚀性的可行性和适用性。因此，成功合成了负载钼酸盐的高岭土纳米管（HNT@MO）并将其掺入砂浆中。结果表明：钼酸盐离子的释放能促进钢表面氧化保护膜的形成，抑制氯化物侵蚀引起的腐蚀过程；此外，HNT@MO的掺入通过细化微观结构和降低孔隙率来提高砂浆的力学性能。因此，HNT@MO的协同缓蚀作用提高了砂浆中钢的抗氯化物腐蚀性能。

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引用次数: 0

Does crack localization occur at the peak tensile strength of strain-hardening slag composites? A statistical approach 应变硬化渣复合材料抗拉强度峰值处是否出现裂纹局部化？统计方法

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

Cement & concrete composites

Pub Date : 2026-01-17 DOI: 10.1016/j.cemconcomp.2026.106482

Dongsun Lee , Nemkumar Banthia , Doo-Yeol Yoo

This study examines the validity of the conventional assumption that crack localization and peak tensile stress occur simultaneously in high-performance fiber-reinforced cementitious composites, with emphasis on the useable tensile strain prior to localization-induced softening. Statistical analysis was performed using direct tensile test data from 70 strain-hardening slag-based composites tested with digital image correlation (DIC). Crack-width histories obtained from the DIC images were denoised using outlier removal and smoothing splines. The onset of localization was identified as the time at which the curvature (second derivative) of the dominant crack-width curve reached a pronounced maximum. The strain at localization was then quantitatively compared with the strain at peak tensile stress. For specimens exhibiting typical strain-hardening behavior, the localization-to-peak strain ratio had an average value close to unity. A 95 % prediction interval indicated that localization generally occurred between approximately 94 % and 107 % of the peak strain. On the stress axis, a beta-distribution model with bootstrap verification yielded a one-sided 95 % prediction interval of approximately 97–100 % for the stress at localization relative to the peak stress, showing that the two stresses are practically indistinguishable in most cases. These bounds define a strain–stress prediction box enclosing about 95 % of the observed localization points, which are superimposed on a conventional tensile stress–strain curve to conservatively estimate localization. A small subset of specimens showed delayed localization at larger strains while maintaining near-peak stress, attributed to time-dependent degradation of fiber-bridging capacity. The proposed framework supports localization-aware tensile design and helps avoid underestimation of tensile performance.

本研究检验了传统假设的有效性，即高性能纤维增强胶凝复合材料中裂纹局部化和峰值拉应力同时发生，重点研究了局部化诱发软化之前的可用拉应变。采用数字图像相关（DIC）技术对70种应变硬化渣基复合材料的直接拉伸试验数据进行了统计分析。利用离群值去除和平滑样条对DIC图像的裂缝宽度历史进行去噪。局部化的开始被确定为主要裂缝宽度曲线的曲率（二阶导数）达到显著最大值的时间。然后将局部应变与峰值拉应力应变进行定量比较。对于具有典型应变硬化行为的试样，局部应变-峰值应变比的平均值接近于1。95%的预测区间表明，局部化一般发生在峰值应变的94% ~ 107%之间。在应力轴上，一个带有bootstrap验证的beta分布模型对局部应力相对于峰值应力产生了大约97 - 100%的单侧95%的预测区间，这表明在大多数情况下，这两个应力实际上是无法区分的。这些边界定义了一个应变-应力预测框，其中包含约95%的观察到的局部化点，这些点叠加在传统的拉伸应力-应变曲线上，以保守地估计局部化。一小部分样品在较大应变下显示延迟定位，同时保持接近峰值的应力，归因于纤维桥接能力的时间依赖性退化。提出的框架支持局部感知拉伸设计，并有助于避免拉伸性能的低估。

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引用次数: 0

Interfacial effects of thermal energy storage aggregates on the thermo-mechanical properties of cementitious composites 蓄热聚集体对胶凝复合材料热力学性能的界面效应

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

Cement & concrete composites

Pub Date : 2026-01-16 DOI: 10.1016/j.cemconcomp.2026.106487

Haibin Yang , Weiyu Zhang , Lulu Hao , Yihang Ye , Rongtao Zeng , Weiyi Zhang , Hongzhi Cui

Interface engineering plays a pivotal role in the successful encapsulation and integration of phase change materials (PCM) into cementitious composites for building energy applications. However, the incorporation of thermal energy storage aggregates (TESA) in such composites often results in compromised mechanical properties and inefficient heat transfer due to poor interfacial compatibility between TESA and cementitious composites matrix. In this study, we presented a bottom-up encapsulation strategy combining in situ polymerization with droplet granulation to fabricate TESA using sodium sulfate decahydrate as the PCM core, achieving a high latent heat of 129.5 J/g. To overcome interface-related limitations, silicon carbide (SiC) particles were embedded within the polymer shell to form a thermally conductive and structurally reinforcing interfacial layer. Both experimental and numerical analyses demonstrated that the improved interface accelerates latent heat utilization and lowers indoor temperature peaks, thereby enhancing thermal regulation. Simultaneously, interfacial strengthening promotes better bonding between TESA and the cement matrix, mitigating strength degradation and improving durability under thermal cycling. Overall, this work revealed the pivotal role of interface design in achieving high-performance energy storage cementitious composites, offering a scalable pathway to enhance both the thermal efficiency and structural viability in sustainable building materials.

界面工程在相变材料（PCM）成功封装和集成到建筑能源应用的胶凝复合材料中起着关键作用。然而，在这种复合材料中加入热储能聚集体（TESA）往往会导致力学性能受损和传热效率低下，因为TESA与胶凝复合材料基体之间的界面相容性差。在本研究中，我们提出了一种自下而上的封装策略，将原位聚合与液滴造粒相结合，以十水硫酸钠为PCM核心制备TESA，获得了129.5 J/g的高潜热。为了克服与界面相关的限制，将碳化硅（SiC）颗粒嵌入聚合物外壳中，形成导热和结构增强的界面层。实验和数值分析均表明，改进的界面加速了潜热利用，降低了室内温度峰值，从而增强了热调节。同时，界面强化促进了TESA与水泥基体之间更好的结合，减轻了强度退化，提高了热循环下的耐久性。总的来说，这项工作揭示了界面设计在实现高性能储能胶凝复合材料中的关键作用，为提高可持续建筑材料的热效率和结构可行性提供了一条可扩展的途径。

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引用次数: 0

Assessment of environmental and mechanical factors affecting cement-based triboelectric nanogenerators: Stability and durability 影响水泥基摩擦电纳米发电机的环境和机械因素的评估：稳定性和耐久性

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

Cement & concrete composites

Pub Date : 2026-01-16 DOI: 10.1016/j.cemconcomp.2026.106489

Wenkui Dong , Caiyu Zhao , Ziyan Gao , Linguangze Zhuo , Guoxu Liu , Jin Zhang , Shuhua Peng , Chi Zhang , Surendra P. Shah , Wengui Li

Cement-based triboelectric nanogenerators (CBTENGs) offer a transformative pathway toward self-powering and intelligent transportation infrastructure by harvesting mechanical energy from pavement surfaces. However, their practical deployment requires a comprehensive understanding of their environmental and mechanical durability and adaptability. This study presents the first systematic durability assessment of CBTENGs under combined environmental and mechanical interferences, investigating their stability under diverse service conditions, including temperature, relative humidity, freeze-thaw and wet-dry cycling, acid attack, abrasion, dynamic impact loading, and fatigue. The results reveal that output current increases by up to 35 % as temperature rises from −20 °C to 80 °C, mainly attributed to enhanced interfacial polarization, increased dielectric mobility, improved charge localization, and reduced energy barriers. An optimal humidity level (∼50 % relative humidity) maximizes charge generation through hydrogen bond-mediated dipole alignment, whereas excessive moisture induces conductive pathways, leading to approximately 28 % output degradation. The devices retain over 90 % of their initial output after 20 freeze-thaw or wet-dry cycles and maintain stable performance over 9000 fatigue cycles. Nevertheless, sulfuric acid exposure reduces output by 55 %, highlighting chemical degradation as the dominant deterioration mode. The results establish the environmental and mechanical reliability of CBTENGs and elucidate the microstructural and interfacial mechanisms governing charge retention, providing a robust foundation for the development of durable and efficient energy-harvesting pavement systems.

水泥基摩擦电纳米发电机（CBTENGs）通过从路面表面收集机械能，为自供电和智能交通基础设施提供了一种革命性的途径。然而，它们的实际部署需要全面了解其环境和机械耐久性和适应性。本研究首次系统评估了cbteng在环境和机械综合干扰下的耐久性，研究了其在不同使用条件下的稳定性，包括温度、相对湿度、冻融和干湿循环、酸侵蚀、磨损、动态冲击载荷和疲劳。结果表明，当温度从- 20°C升高到80°C时，输出电流增加了35%，这主要是由于界面极化增强、介电迁移率增加、电荷局部化改善和能量势垒降低。最佳湿度水平（约50%相对湿度）通过氢键介导的偶极子排列使电荷产生最大化，而过度的湿度诱导导电途径，导致大约28%的输出退化。经过20次冻融或干湿循环后，设备保持90%以上的初始产量，并在9000次疲劳循环中保持稳定的性能。然而，硫酸暴露会使产量减少55%，这表明化学降解是主要的降解方式。研究结果建立了cbteng的环境和力学可靠性，并阐明了控制电荷保留的微观结构和界面机制，为开发耐用、高效的能量收集路面系统提供了坚实的基础。

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引用次数: 0

Thermochromic coatings for self-sensing seawater-mixed cementitious sensors: towards multifunctional applications in concrete pavements 自感海水混合胶凝传感器的热致变色涂层：在混凝土路面上的多功能应用

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

Cement & concrete composites

Pub Date : 2026-01-16 DOI: 10.1016/j.cemconcomp.2026.106488

Zhizhong Deng , Quang Dieu Nguyen , Aziz Hasan Mahmood , Wengui Li , Daichao Sheng

This work explores the integration of thermochromic materials and self-sensing cementitious sensors to advance the development of multifunctional pavement systems. By employing seawater as the mixing medium, the pore solution chemistry is deliberately modified through elevated ionic concentrations, thereby enabling new pathways for performance enhancement and sustainability in coastal infrastructure. The temperature regulation capability of three different thermochromic (TC) coatings was experimentally verified, achieving a maximum temperature reduction of approximately 20.5 °C. With the TC coating, the rate of water loss of pore solutions was measured in this study. To demonstrate the solar radiation reflection, transmittance, and intensity of light, UV–Vis Spectroscopy (UV), Fourier transform infrared spectroscopy (FTIR), and Raman spectroscopy (RS) methodologies have been applied in this research. Due to the high absorbance of visible light and near-infrared (NIR) radiation, more energy can be absorbed by the cement surface, causing the temperature of pure cementitious specimens to rise rapidly. With a suitable range of water saturation in cementitious mixtures (95–100 %), the ion conduction of self-sensing cementitious sensors has been improved. An elevated ion concentration within the self-sensing sensors stabilises their piezoresistive response, yielding a more consistent relationship between cyclic pressure variations and corresponding resistance changes. In addition, the incorporation of thermochromic coatings enables effective temperature regulation of the composites under solar irradiation. The compressive strength of the samples was enhanced by the 65 °C heating. After 72 h of heating, the strength improved due to the acceleration of the hydration of cement particles. The combination of TC materials and self-sensing function improved the mechanical and piezoresistivity properties of the cementitious matrix. It proved the application potential of multifunctional cementitious mixtures in pavement.

这项工作探讨了热致变色材料和自传感胶凝传感器的集成，以推进多功能路面系统的发展。通过使用海水作为混合介质，通过提高离子浓度有意地改变孔隙溶液的化学性质，从而为沿海基础设施的性能增强和可持续性提供了新的途径。实验验证了三种不同的热致变色（TC）涂层的温度调节能力，最大温度降低约20.5°C。采用TC涂层，测量了孔隙溶液的失水速率。为了证明太阳辐射的反射、透射和光强，本研究应用了紫外-可见光谱（UV）、傅里叶变换红外光谱（FTIR）和拉曼光谱（RS）等方法。由于对可见光和近红外（NIR）辐射的高吸光度，水泥表面可以吸收更多的能量，导致纯胶凝试件的温度迅速上升。在合适的胶凝混合物含水饱和度范围内（95 - 100%），自传感胶凝传感器的离子传导得到了改善。自传感传感器内离子浓度的升高稳定了它们的压阻响应，从而在循环压力变化和相应电阻变化之间产生更一致的关系。此外，热致变色涂层的加入使复合材料在太阳照射下的温度调节变得有效。经65℃加热后，试样的抗压强度有所提高。加热72h后，由于水泥颗粒水化速度加快，强度提高。TC材料与自传感功能的结合改善了胶凝基质的力学性能和压阻性能。证明了多功能胶凝料在路面中的应用潜力。

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引用次数: 0

Tailored Poisson’s Ratio-reinforced Cementitious Composites for flexural applications 为弯曲应用量身定制的泊松比增强胶凝复合材料

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

Cement & concrete composites

Pub Date : 2026-01-16 DOI: 10.1016/j.cemconcomp.2026.106485

Rowin J.M. Bol , Wen Zhou , Zhaozheng Meng , Erik Schlangen , Branko Šavija

The use of Additive Manufacturing (AM) to create reinforcements for cementitious composites has become a popular research topic in recent years. One illustrative example is the integration of 3D-printed auxetic reinforcements into cementitious matrices, which exhibit superior energy absorption due to their negative Poisson’s ratio. This presents the opportunity to tailor the Poisson’s ratio of reinforcements to align with local stress distributions and enhance structural efficiency. In this study, Tailored Poisson’s Ratio-reinforcements (TPR) were proposed, characterized by a linear gradient of Poisson’s ratios along the height of the reinforcement to accommodate varying stress profiles within beams. Specifically, the top chords of TPR exhibit negative Poisson’s ratios (auxetic), undergoing lateral contraction under compression and providing confinement to the surrounded matrix. Conversely, the bottom chords possess positive Poisson’s ratios, contributing to lateral contraction under tension. These lateral deformations cause a shift in the principal stress state of the confined matrix, extending the loading path in stress space and actively delaying failure. Three novel Tailored Poisson’s Ratio-reinforced Cementitious Composite (TPRCC) designs are developed and tested under four-point bending in this study. Experimental recordings indicate increases in load capacity and toughness of up to 191% and 6900% with respect to plain mortar, respectively.

近年来，利用增材制造（AM）为胶凝复合材料制造增强材料已成为一个热门的研究课题。一个说明性的例子是将3d打印的增强型增强材料集成到胶凝基质中，由于它们的负泊松比，它表现出优越的能量吸收。这提供了机会，量身定制的泊松比的加强，以对准局部应力分布和提高结构效率。在这项研究中，提出了定制泊松比-钢筋（TPR），其特征是泊松比沿钢筋高度呈线性梯度，以适应梁内不同的应力剖面。具体而言，TPR的上弦表现为负泊松比（auxetic），在压缩下发生侧向收缩，并对周围的基质提供约束。相反，底部和弦具有正的泊松比，有助于张力下的侧向收缩。这些侧向变形引起了封闭基体主应力状态的变化，延长了应力空间中的加载路径，主动延缓了破坏时间。本研究开发了三种新颖的定制泊松比增强胶凝复合材料（TPRCC）设计，并在四点弯曲下进行了测试。实验记录表明，与普通砂浆相比，其承载能力和韧性分别提高了191%和6900%。

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引用次数: 0

Mechanical and adhesive properties of alkali-activated fly ash (AAF) and alkali-activated slag (AAS) at the nano- and micro-scales 碱活性粉煤灰（AAF）和碱活性渣（AAS）在纳米和微尺度上的力学性能和粘接性能

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

Cement & concrete composites

Pub Date : 2026-01-13 DOI: 10.1016/j.cemconcomp.2026.106483

Kongfa Zhu , Hongliang Zhang , Yujiao Zhu , Qihan Zhong , Demei Yu

The adhesive and nanomechanical properties of alkali-activated materials (AAMs) remain poorly understood, despite being crucial for explaining their macroscopic mechanical and deformation behaviors. Here, Atomic force microscopy-quantitative nanomechanical mapping (AFM-QNM) was utilized to characterize the mechanical and adhesive properties of alkali-activated fly-ash (AAF) and alkali-activated slag (AAS) across multiple scanning scales (50 μm–500 nm). The moduli and adhesion of distinct sub-constituents were deconvoluted at different scales and the relationships between the nanoscale mechanical and adhesive characteristics of basic building blocks and the properties of gel clusters and reaction products were established to reveal the origin of these properties. Comparisons of the differences in composition, nanomechanical and adhesive characteristics between N-A-S-H and C-A-S-H basic building blocks elucidate how these differences influence the properties of gel clusters and reaction products. The results indicate that for AAF, grain comprises wrinkled peak and valley regions. Peak zones dominate grain-level mechanics and adhesion, while valleys modulate these properties. This nanoscale relationship extends to higher scales. The properties of N-A-S-H gel clusters and reaction products are largely inherited from the peak regions. In AAS, a distinct intermediate “unit-cell” structure, formed by aggregated nanograins, promotes the formation of a high-density phase within C-A-S-H clusters. The mechanical and adhesive properties of the resulting products may originate from these unit cells, with nanograins providing secondary modulation. The presence of unit cell structure accounts for the superior compressive and flexural strength of AAS compared to AAF. These insights inform the hierarchical modeling and targeted design of AAMs.

尽管对于解释碱活化材料的宏观力学和变形行为至关重要，但其粘附性和纳米力学性能仍然知之甚少。本文采用原子力显微镜-定量纳米力学作图（AFM-QNM）技术，在多个扫描尺度（50μm ~ 500nm）上对碱活化粉煤灰（AAF）和碱活化渣（AAS）的力学性能和粘附性能进行了表征。在不同尺度上对不同亚组分的模量和粘附力进行解卷积，并建立基本构建块的纳米尺度力学和粘附特性与凝胶团簇和反应产物性质之间的关系，以揭示这些性质的来源。比较了N-A-S-H和C-A-S-H基本构建块在组成、纳米力学和粘附特性方面的差异，阐明了这些差异如何影响凝胶团簇和反应产物的性质。结果表明，在AAF条件下，颗粒由褶皱峰区和褶皱谷区组成。峰区主导晶粒级力学和粘附性，而谷区调节这些特性。这种纳米级的关系延伸到更高的尺度。N-A-S-H凝胶团簇和反应产物的性质在很大程度上继承于峰区。在原子吸收光谱中，由聚集的纳米颗粒形成的独特的中间“单位细胞”结构促进了C-A-S-H簇内高密度相的形成。所得产品的机械和粘合性能可能源于这些单晶，纳米颗粒提供二次调制。与AAF相比，AAS具有较好的抗压和抗弯强度。这些见解为aam的分层建模和目标设计提供了信息。

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引用次数: 0