Cement and Concrete Research最新文献_第8页

Factors that govern the electrical, dielectric, and electromagnetic properties of hardened fly ash-based geopolymer composites 影响硬化粉煤灰基地聚合物复合材料电学、介电和电磁性能的因素

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

Cement and Concrete Research

Pub Date : 2025-10-17 DOI: 10.1016/j.cemconres.2025.108062

Xiang Xi , Zijie Zhao , Wenkui Dong , Jingming Cai , Yue Gu , Wenyi Zhang , Hongqiang Chu , Qianping Ran

This study investigates the factors influencing the electrical, dielectric, and electromagnetic properties of fly ash-based geopolymer pastes (GP) by comparing their electrical resistivity, relative permittivity, and electromagnetic interference (EMI) shielding effectiveness under varying design parameters, including the water-to-binder (W/B) ratio, alkali modulus, and slag content. The results reveal that both DC and AC resistivity increase with a lower W/B ratio, higher alkali modulus, and greater slag content. Conversely, relative permittivity increases with a higher W/B ratio, lower alkali modulus, and greater slag content. These electrical and dielectric properties are interrelated, as they both depend on microstructural characteristics and their effects on charge movement and concentration. The predominant EMI shielding mechanism, whether reflection or absorption, is determined by the design parameters. Specifically, a higher W/B ratio correlates with greater reflection loss due to high relative permittivity and conductivity. A higher alkali modulus is associated with increased total shielding loss, also driven by high relative permittivity and conductivity. When slag content is increased, high resistivity combined with moderate relative permittivity leads to higher total shielding loss. The reflection of electromagnetic waves by GP is attributed to the impedance mismatch between the GP and air, while absorption results from conduction loss and polarization losses, including dipolar polarization, polarization relaxation, interfacial polarization, and molecular currents. This study provides valuable insights into the potential of geopolymers as functional materials.

本研究通过比较不同设计参数（水胶比、碱模量和矿渣含量）下粉煤灰基地聚合物膏体（GP）的电阻率、相对介电常数和电磁干扰（EMI）屏蔽效果，探讨了影响其电学、介电和电磁性能的因素。结果表明，随着W/B比的降低、碱模量的增大和渣含量的增加，直流电阻率和交流电阻率均增大。相反，相对介电常数随W/B比的增大、碱模量的减小和渣量的增大而增大。这些电学和介电性能是相互关联的，因为它们都取决于微观结构特征及其对电荷运动和浓度的影响。主要的电磁干扰屏蔽机制，无论是反射还是吸收，是由设计参数决定的。具体来说，由于相对介电常数和电导率较高，较高的W/B比与较大的反射损耗相关。较高的碱模量与增加的总屏蔽损失有关，这也是由较高的相对介电常数和电导率驱动的。当渣量增加时，高电阻率和适度的相对介电常数会导致更高的总屏蔽损失。电磁波被GP反射的原因是GP与空气之间的阻抗失配，而吸收的原因是传导损失和极化损失，包括偶极极化、极化弛豫、界面极化和分子电流。这项研究为地聚合物作为功能材料的潜力提供了有价值的见解。

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引用次数: 0

A photometric stereo and Vision Transformer-based framework for automated air void analysis in hardened concrete 一种基于光立体和视觉变换的硬化混凝土中空隙自动分析框架

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

Cement and Concrete Research

Pub Date : 2025-10-16 DOI: 10.1016/j.cemconres.2025.108063

Xiangdong Yan, Alessandro Fascetti

Air void analysis in hardened concrete typically requires the Linear Traverse Method (Procedure A) or the Modified Point-Count Method (Procedure B), as described in ASTM C457, to assess the content and distribution of entrapped and entrained air voids. These parameters are critical for assessing freeze–thaw resistance, workability, and mechanical properties. Conventional approaches rely on manual sampling and inspection by trained technicians, which are not only time-consuming and labor-intensive but also inherently subjective due to operator-dependent interpretations. This study proposes a novel framework integrating Photometric Stereo and Vision Transformer models to automate air void analysis with enhanced speed, accuracy, and generalizability. By leveraging a newly designed photometric stereo system and a computer vision-based image processing pipeline, the proposed method addresses key limitations in existing techniques, such as the inability to detect shallow or deep voids, incomplete boundary identification, and challenges in distinguishing air voids from aggregates. The framework seamlessly integrates image acquisition, recognition, extraction, and analysis, completing the entire process within approximately 10 min, excluding initial specimen preparation. When compared to current automated petrographic analysis methods, this approach achieves state-of-the-art precision, with mean accuracies of 97.970% for air void content and 97.176% for spacing factor, while eliminating the need for surface treatments or extensive model training. Furthermore, the study reports a comprehensive sensitivity analysis of parameter selection in Procedures A and B, offering deeper insights into ASTM C457 specifications. The proposed solution significantly reduces time and labor costs associated with air void analysis, enhances result reliability, and demonstrates potential for broader applications in micro-scale 3D surface reconstruction and property evaluation.

硬化混凝土中的空隙分析通常需要ASTM C457中描述的线性导线法（程序A）或修改点计数法（程序B）来评估被困和夹带的空隙的含量和分布。这些参数对于评估抗冻融性、可加工性和机械性能至关重要。传统的方法依赖于训练有素的技术人员进行人工采样和检查，这不仅耗时费力，而且由于操作人员的解释，这本身就是主观的。本研究提出了一种新的框架，集成了光度立体和视觉转换模型，以提高速度，准确性和通用性来自动化空隙分析。通过利用新设计的光度立体系统和基于计算机视觉的图像处理管道，该方法解决了现有技术的关键局限性，例如无法检测浅孔或深孔、边界识别不完整以及在区分空气空洞和聚集物方面存在的挑战。该框架无缝集成了图像采集、识别、提取和分析，在大约10分钟内完成整个过程，不包括最初的标本制备。与目前的自动化岩石学分析方法相比，该方法达到了最先进的精度，空隙含量的平均精度为97.970%，间距因子的平均精度为97.176%，同时无需进行表面处理或大量的模型训练。此外，该研究报告了程序a和B中参数选择的全面敏感性分析，为ASTM C457规范提供了更深入的见解。该解决方案大大减少了与空隙分析相关的时间和人工成本，提高了结果的可靠性，并在微尺度3D表面重建和性能评估方面展示了更广泛的应用潜力。

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引用次数: 0

Robust superhydrophobic cementitious composites with ex-situ carbonation: Performance and mechanism 非原位碳化的超疏水胶凝复合材料：性能和机理

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

Cement and Concrete Research

Pub Date : 2025-10-11 DOI: 10.1016/j.cemconres.2025.108059

Yifeng Ling , Guang Yin , Lijun Wang , Hui Jin , Bo Li , Weizhuo Shi , Shilang Xu

Superhydrophobic surfaces have attracted significant attention due to their ability to enhance the durability of concrete by preventing water and aggressive agent penetration. However, traditional superhydrophobic materials have limitations, being poorly durable and prone to wear. In this study, we propose a novel design for robust superhydrophobic cementitious composites: nano-CaCO₃ is grown ex-situ on fly ash particles to ensure the complete leaching of Ca²⁺ from carbide slag during carbonation, which also allows nano-CaCO₃ to be uniformly introduced into the composite through a carrier effect of carbonated fly ash. In addition, fluoroalkylsilane was incorporated into the carbon-sequestered composite to further reduce surface energy and achieve superhydrophobicity. The results demonstrate that the hydrophobicity of the composites is closely tied to the carbonation process, with a contact angle of 163.0° which signifies a superhydrophobic condition. This study provides valuable insights into the innovative design and production of carbon-sequestered, robust superhydrophobic cement-based materials.

超疏水表面由于其通过防止水和侵蚀剂渗透来提高混凝土耐久性的能力而引起了人们的极大关注。然而，传统的超疏水材料存在耐久性差、易磨损等局限性。在这项研究中，我们提出了一种坚固的超疏水胶凝复合材料的新设计：纳米caco₃在粉煤灰颗粒上非原位生长，以确保碳化过程中电石渣中的Ca2+完全浸出，这也允许纳米caco₃通过碳化粉煤灰的载体效应均匀地引入复合材料。此外，将氟烷基硅烷加入固碳复合材料中，进一步降低表面能，实现超疏水性。结果表明，复合材料的疏水性与炭化过程密切相关，接触角为163.0°，为超疏水状态。这项研究为碳隔离、坚固的超疏水水泥基材料的创新设计和生产提供了有价值的见解。

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引用次数: 0

CO2 uptake in calcium aluminosilicate materials 钙铝硅酸盐材料对CO2的吸收

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

Cement and Concrete Research

Pub Date : 2025-10-11 DOI: 10.1016/j.cemconres.2025.108056

Subhashree Panda , Luis Schnürer , Alisa Machner , Luis Ruiz Pestana , Prannoy Suraneni

CO₂ mineralization has gained increasing attention as a strategy to reduce emissions from concrete production. This study investigates the carbonation potential of several calcium aluminosilicate (CAS) materials, model systems for understanding supplementary cementitious materials (SCMs). CAS materials were synthesized at temperatures ranging from 1000 °C to 1600 °C, producing structures ranging from partially crystalline to fully amorphous. X-ray diffraction and scanning electron microscopy were used to understand material physicochemical properties. Carbonation potential was assessed through CO₂ uptake measurements using thermogravimetric analysis and Fourier-transform infrared spectroscopy, while SCM reactivity was evaluated via a modified R³ test. Results show that materials synthesized at 1000 °C and 1200 °C, containing unreacted oxides, portlandite, CA, and C₂S, exhibited the highest CO₂ uptake but the lowest reactivity as SCM. In contrast, fully amorphous glasses synthesized at 1600 °C demonstrated significantly higher SCM reactivity but minimal CO₂ uptake. These findings highlight a fundamental trade-off between their reactivity and carbonation potential, governed by the degree of amorphization.

二氧化碳矿化作为一种减少混凝土生产排放的策略越来越受到关注。本研究探讨了几种硅酸铝钙（CAS）材料的碳化潜力，作为理解补充胶凝材料（SCMs）的模型系统。合成CAS材料的温度范围从1000℃到1600℃，产生的结构范围从部分结晶到完全非晶。利用x射线衍射和扫描电镜了解材料的物理化学性质。通过使用热重分析和傅里叶变换红外光谱测量CO2吸收来评估碳化势，而通过改进的R3测试来评估SCM的反应性。结果表明，在1000°C和1200°C合成的含未反应氧化物、硅酸盐、CA和C2S的材料，作为SCM的CO2吸收量最高，但反应性最低。相比之下，在1600°C下合成的全非晶玻璃显示出明显更高的SCM反应性，但二氧化碳吸收最小。这些发现强调了它们的反应性和碳酸化潜力之间的基本权衡，这是由非晶化程度决定的。

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引用次数: 0

Influence of FRP rebar polymer matrix leachates on cement hydration and bond performance in FRP-reinforced concrete 玻璃钢钢筋聚合物基质浸出液对玻璃钢混凝土水泥水化及粘结性能的影响

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

Cement and Concrete Research

Pub Date : 2025-10-10 DOI: 10.1016/j.cemconres.2025.108051

Amir Behravan , Cooper Davenport , Emily Spradley , B. Dulani Dhanapala , Bernard Kassner , Stephen Sharp , Alyson Daniels

Fiber-reinforced polymer (FRP) rebars are increasingly used in construction due to their advantages over conventional steel reinforcement. However, well-established standards and design codes for all FRP types remain limited. While most previous studies have focused on the mechanical bond between FRP rebars and concrete, this study provides a detailed investigation of how organic compounds leached from FRP rebars affect cement hydration kinetics and, consequently, bond performance. Ten different FRP rebars—including glass (GFRP), basalt (BFRP), and carbon (CFRP) types—were examined. Analytical techniques such as total organic carbon (TOC), ICP-MS, and FTIR confirmed the leaching of organic compounds from the rebars. Subsequent experiments using isothermal calorimetry, SEM, and mechanical testing assessed how these leachates influence cement hydration in the vicinity of the rebars. The results indicate that specific organic compounds from the polymer matrix can negatively affect hydration in the transition zone, reducing the quality of the interfacial bond between FRP rebars and the cementitious matrix. These findings highlight the importance of chemical interactions at the FRP–concrete interface and suggest that both improvements to the rebar surface and modifications to the concrete mixture should be considered. Given the variability among different FRP rebars, a single universal design guideline may not be sufficient for all products.

纤维增强聚合物（FRP）钢筋由于其优于传统钢筋的优点而越来越多地应用于建筑中。然而，所有FRP类型的完善标准和设计规范仍然有限。虽然之前的大多数研究都集中在FRP筋与混凝土之间的机械结合上，但本研究提供了从FRP筋中浸出的有机化合物如何影响水泥水化动力学，从而影响结合性能的详细调查。研究了10种不同的FRP筋，包括玻璃（GFRP）、玄武岩（BFRP）和碳（CFRP）。总有机碳（TOC）、ICP-MS和FTIR等分析技术证实了钢筋中有机化合物的浸出。随后的实验使用等温量热法、扫描电镜和力学测试来评估这些渗滤液如何影响钢筋附近的水泥水化。结果表明，来自聚合物基体的特定有机化合物会对过渡区水化产生负面影响，降低FRP筋与胶凝基质之间的界面结合质量。这些发现强调了frp -混凝土界面化学相互作用的重要性，并建议应考虑改进钢筋表面和修改混凝土混合物。考虑到不同FRP筋之间的可变性，单一的通用设计准则可能不足以适用于所有产品。

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引用次数: 0

Carbonation behavior of Portland cement incorporating polycarboxylate ether superplasticizer: Towards carbonation kinetics, microstructural evolution and mechanical properties 掺聚羧酸醚减水剂硅酸盐水泥的碳化行为：碳化动力学、微观结构演变和力学性能研究

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

Cement and Concrete Research

Pub Date : 2025-10-10 DOI: 10.1016/j.cemconres.2025.108061

Jionghuang He , Guangcheng Long , Yi Jiang , Qinglong Qin , Cong Tang , Yong Tao , Peiliang Shen , Chi-Sun Poon

Polycarboxylate ether (PCE) superplasticizers are crucial in modern concrete, yet their compatibility with carbonation curing, a promising CO₂ sequestration method, remains insufficiently understood. This study systematically examined carbonation behavior of Portland cement (PC) incorporating PCE by analyzing its phase assemblage, microstructure, carbonation heat, solution chemistry and mechanical properties. Results indicated that PCE significantly reduced the carbonation rate. The peak rate of carbonation heat in pure PC reached 0.57 W/g, while the addition of 2.0 % PCE reduced this value by 43.9 %. This reduction was attributed to the adsorption and complexation effects of PCE, the immobilization of CaCO₃ clusters within polymer network, as well as a rapid decrease in solution pH. Furthermore, the aggressive carbonation kinetics amplified the detrimental impact of PCE on microstructural development. This inhibited carbonation at particle boundaries and weakened interparticle bonding, thereby leading to a decline in mechanical performance. These findings offer fundamental insights into the compatibility and limitations of using PCE in combination with carbonation technologies in concrete.

聚羧酸醚（PCE）高效减水剂在现代混凝土中至关重要，但它们与碳化固化（一种很有前途的二氧化碳封存方法）的相容性仍未得到充分了解。本研究通过分析PCE硅酸盐水泥的相组合、微观结构、碳化热、溶液化学和力学性能，系统地考察了PCE硅酸盐水泥的碳化行为。结果表明，PCE显著降低了碳酸化速率。纯PC的碳化热峰值为0.57 W/g，而添加2.0%的PCE使碳化热峰值降低了43.9%。这种减少归因于PCE的吸附和络合作用、CaCO3簇在聚合物网络中的固定化以及溶液ph的快速降低。此外，积极的碳化动力学放大了PCE对微观结构发育的有害影响。这抑制了颗粒边界的碳化，削弱了颗粒间的结合，从而导致机械性能下降。这些发现为PCE与混凝土碳化技术结合使用的兼容性和局限性提供了基本的见解。

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引用次数: 0

Sulfate adjustment and early reactivity in cements containing kaolinitic calcined clays: investigation and assessment via a sulfate-limited model system 硫酸盐调节和含高岭石煅烧粘土的水泥的早期反应性：通过硫酸盐限制模型系统的研究和评估

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

Cement and Concrete Research

Pub Date : 2025-10-10 DOI: 10.1016/j.cemconres.2025.108060

Tafadzwa Ronald Muzenda , Yannick Demeusy , Fabien Georget , Christophe Labbez , Thomas Matschei

Understanding the early reaction kinetics of calcined clays (CCs) in calcined clay-limestone cements (CCLC) is required to optimize the formulations for optimal early performance. In this study, a clinker-free sulfate-limited model system (SLiM) is utilized to compare the early reactivity of 9 diverse natural CCs. The SLiM consists of an excess of CC and portlandite, and limited gypsum It is demonstrated that the sulfate-carrier depletion time provides a rate of reaction for each clay which is characteristic of its reactivity in a blended cement. As such, it is shown that the SLiM test can be used to probe physico-chemical properties, including the standard enthalpy of formation of metakaolinite, and to understand the mechanical performance and hydration of blended cement with these clays up to 3 days. In conclusion, a foundation for a standard test allowing to adjust gypsum content in CCLC from a single calorimetry measurement is developed.

了解煅烧粘土（CCs）在煅烧粘土-石灰石水泥（CCLC）中的早期反应动力学是优化配方以获得最佳早期性能的必要条件。本研究采用无熟料硫酸盐限制模型系统（SLiM）比较了9种不同天然cc的早期反应性。SLiM由过量的CC和波特兰硅酸盐和有限的石膏组成。硫酸盐载体耗尽时间为每种粘土提供了反应速率，这是混合水泥中其反应性的特征。因此，SLiM测试可以用于探测偏高岭石的物理化学性质，包括标准形成焓，并了解这些粘土混合水泥的力学性能和水化作用长达3天。总之，开发了一个标准测试的基础，允许调整CCLC中的石膏含量，从单一的量热法测量。

引用次数: 0

Clinoptilolite zeolite as a substrate for alkali-boosting cement hydration 斜沸石作为底物对水泥的碱促水化作用

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

Cement and Concrete Research

Pub Date : 2025-10-10 DOI: 10.1016/j.cemconres.2025.108057

M. Shariful Islam , Joseph J. Biernacki , Benjamin J. Mohr

Clinoptilolite-Ca zeolite exhibited limited pozzolanic activity at early ages in portland cement systems, resulting in slower initial hydration and strength development. Conversion of Ca-zeolite to Na- or K-forms, combined with increasing the pH of the blended system through pH engineering of the treated zeolite, substantially enhanced its reactivity. Calorimetry revealed accelerated C₃S and C₃A hydration, with higher peak intensities and shorter dormancy periods for Na-or-K zeolites, whereas bulk portlandite analysis indicated that Ca-zeolite inhibits clinker reactions. Phase-resolved quantitative EDS confirmed these trends, showing retardation of hydration for Ca-zeolite and promotion of both silicate and aluminate phases reactions for Na-and K-zeolites, along with the formation of relatively higher amounts of AFm phases. Chemical shrinkage and mortar strength measurements further supported these findings. Notably, pH-engineered zeolites increased early-age strength by up to 10 %, with 7-days mortar strength remaining equivalent even at 20 % cement replacement, highlighting their potential as sustainable supplementary cementitious materials.

斜沸石-钙沸石在硅酸盐水泥体系早期表现出有限的火山灰活性，导致初始水化和强度发展较慢。将ca型沸石转化为Na型或k型沸石，再加上通过处理沸石的pH工程提高混合体系的pH值，大大提高了其反应性。量热分析表明，na -或k型沸石能加速C₃S和C₃A的水化反应，其峰值强度更高，休眠时间更短，而硅酸盐分析表明，ca型沸石能抑制熟料反应。相分辨定量EDS证实了这些趋势，表明ca -沸石的水化反应迟缓，而na -沸石和k -沸石的硅酸盐和铝酸盐相反应促进，同时形成相对较多的AFm相。化学收缩和砂浆强度测量进一步支持了这些发现。值得注意的是，ph工程沸石将早期强度提高了10%，即使在20%的水泥替代下，7天砂浆强度仍保持不变，这凸显了它们作为可持续补充胶凝材料的潜力。

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引用次数: 0

Accelerated carbonation fronts in cement pastes: Mechanistic insights and simplified modeling 水泥浆体中的加速碳化前沿：力学见解和简化建模

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

Cement and Concrete Research

Pub Date : 2025-10-09 DOI: 10.1016/j.cemconres.2025.108050

Luge Cheng , Ryo Kurihara , Zhenli Yang , Takahiro Ohkubo , Ryoma Kitagaki , Atsushi Teramoto , Yuya Suda , Ippei Maruyama

This study investigated the carbonation behavior of ordinary Portland cement (OPC), volcanic glass powder (VGP), and limestone-calcined clay cement (LC³) pastes, focusing on the water content distribution, phase assemblages, and microstructural evolution. Spatiotemporal changes in water and mineral phases were tracked using proton nuclear magnetic resonance relaxometry and micro-X-ray diffraction, respectively. A simplified model reproduced the drying front, defined by a material-specific threshold water content, which aligned closely with the experimentally measured carbonation front. This confirmed that carbonation progression is governed by water diffusion, referred to as the “plugging effect”. Furthermore, carbonation advanced until empty space increased to approximately 18 %, resulting from the decalcification-induced agglomeration of calcium (alumino) silicate hydrate (C–(A)–S–H). This limit was consistently observed across pastes with varying Ca/(Si + Al) ratios. These findings provide mechanistic insight into carbonation front development and offer a physically grounded criterion for predicting carbonation depth and assessing CO₂ uptake in sustainable cementitious materials.

本研究研究了普通硅酸盐水泥（OPC）、火山玻璃粉（VGP）和石灰石煅烧粘土水泥（LC3）的碳化行为，重点研究了其含水量分布、相组合和微观结构演变。利用质子核磁共振弛豫仪和微x射线衍射分别跟踪了水相和矿物相的时空变化。一个简化的模型再现了干燥锋，由特定材料的阈值含水量定义，这与实验测量的碳化锋密切相关。这证实了碳酸化过程是由水扩散控制的，称为“堵塞效应”。此外，由于脱钙引起的水合硅酸钙（铝）团聚（C - (A) - s - h），碳化作用继续推进，直到真空空间增加到约18%。这一极限在不同Ca/(Si + Al)比例的膏体中一致观察到。这些发现为碳酸化前沿的发展提供了机理见解，并为预测碳酸化深度和评估可持续胶凝材料的CO 2吸收提供了物理基础标准。

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引用次数: 0

Quantifying reactivity of secondary materials as cement substitutes: Modifications to strength activity index methodology 量化作为水泥替代品的二次材料的反应性：对强度活性指数方法的改进

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

Cement and Concrete Research

Pub Date : 2025-10-08 DOI: 10.1016/j.cemconres.2025.108055

Taohua Ye , Jianzhuang Xiao , Zihan Zhou , Tongbo Sui

Strength activity index (SAI) testing often serves as the benchmark for other reactivity tests, such as the rapid, relevant, and reliable (R³) test. However, the flaws in the SAI methodology compromise its accuracy. In this study, the SAI test is revisited and intensively modified by decoupling SCM physicochemical effects and mitigating the influence of SCM density and water sorption. The modified SAI test is validated using quartz powder (QP) and six secondary materials, including fly ash (FA), ground granulated blast furnace slag (GGBFS), recycled concrete powder (RCP), carbonated RCP (CRCP), and thermoactivated RCP (T650 and T750). The results of the modified SAI test closely align with those of the simplified R³ test (R² > 0.90), confirming the reactivity ranking: GGBFS ≈ FA > T750 ≈ T650 > CRCP > RCP ≈ QP. Moreover, the application conditions of the modified SAI test are also identified. In summary, this study contributes to reliable reactivity quantification to support appropriate SCM utilization in cementitious systems.

强度活度指数（SAI）测试通常作为其他反应性测试的基准，如快速、相关和可靠（R3）测试。然而，SAI方法的缺陷损害了其准确性。在本研究中，通过解耦SCM的物理化学效应，减轻SCM密度和吸水率的影响，对SAI测试进行了重新审视和深入修改。采用石英粉（QP）和粉煤灰（FA）、磨粒高炉渣（GGBFS）、再生混凝土粉（RCP）、碳化RCP （CRCP）和热活化RCP (T650和T750) 6种二次材料进行了改良SAI试验。改良SAI试验结果与简化R3试验结果接近（R2 > 0.90），确定了反应性排序：GGBFS≈FA >； T750≈T650 > CRCP > RCP≈QP。此外，还确定了改进后的SAI试验的适用条件。总之，这项研究有助于可靠的反应性量化，以支持在胶凝体系中适当使用SCM。

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引用次数: 0