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CEMENT

Pub Date : 2026-01-01

引用次数: 0

Sustainable mortar production using volcanic ash and crushed laterite as partial cement replacements 使用火山灰和红土碎石作为部分水泥替代品的可持续砂浆生产

CEMENT

Pub Date : 2025-12-04 DOI: 10.1016/j.cement.2025.100162

Bahiru Bewket Mitikie , Demelash Leyekun Kebede , Walied A. Elsaigh

Cement is a critical construction material globally and particularly in Ethiopia, where its production is energy-intensive, costly, and a major source of greenhouse gas emissions. This study explores the partial replacement of Portland cement with volcanic ash and crushed laterite powder in cement mortar as a sustainable and cost-effective alternative. Preliminary mix designs were prepared with varying proportions of volcanic ash and laterite powder to determine optimal combinations which is equal percentage of volcanic ash and laterite powder as selected based the compressive strength result. Subsequent experimental mixes replaced cement with equal proportion of volcanic ash and laterite soil at 0%, 5%, 10%, 15%, 20%, 25%, and 30% by weight, following ASTM C109 standards. The study assessed characterization, mechanical (compressive strength and ultrasonic pulse velocity), durability (sulfate resistance, porosity, and water absorption), and microstructural properties using Fourier transform infrared (FT-IR), thermogravimetric analysis (TGA), and differential thermal analysis (DTA) analyses. Characterization results showed that volcanic ash and crushed laterite are finer than cement and are predominantly pozzolanic. Bernauer-Emmett-Teller (BET) analysis confirmed their fine particle sizes, contributing to the dense packing of the mortar. At 10% of replacement of cement by equal amount of volcanic ash and laterite soil, the highest compressive strength was recorded 33.1 MPa at 28 days and 46.2 MPa at 56 days. Water absorption decreased with increasing the replacement percentage up to 15%, indicating improved durability. Microstructural analysis revealed a denser morphology due to secondary C-S-H formation and filler effects. Overall, volcanic ash and laterite powder improved both mechanical and durability properties of mortar up to 15% replacement, with optimal performance at 10%. This shows the potential of those pozzolanic as a viable partial cement substitute, promoting sustainable construction practices in Ethiopia.

水泥在全球范围内都是一种重要的建筑材料，尤其是在埃塞俄比亚，水泥的生产是能源密集型的，成本高昂，也是温室气体排放的主要来源。本研究探讨了火山灰和红土粉在水泥砂浆中的部分替代波特兰水泥，作为一种可持续和经济的替代方案。采用不同比例的火山灰和红土粉进行初步配合比设计，根据抗压强度结果确定火山灰和红土粉配比等的最佳配合比。随后的试验混合物按照ASTM C109标准，用同等比例的火山灰和红土代替水泥，重量分别为0%、5%、10%、15%、20%、25%和30%。该研究利用傅里叶变换红外（FT-IR）、热重分析（TGA）和差热分析（DTA）分析评估了表征、机械（抗压强度和超声脉冲速度）、耐久性（抗硫酸盐、孔隙率和吸水性）和微观结构性能。表征结果表明，火山灰和红土碎屑比水泥细，以火山灰为主。伯瑙尔-埃米特-泰勒（BET）分析证实了它们的细颗粒尺寸，有助于砂浆的致密堆积。等量火山灰和红土替代水泥量为10%时，28天抗压强度最高，为33.1 MPa， 56天抗压强度最高，为46.2 MPa。吸水率随着更换率的增加而下降，最高可达15%，这表明耐久性得到了提高。显微结构分析表明，由于二次C-S-H的形成和填料的作用，其形貌更加致密。总的来说，火山灰和红土粉末可使砂浆的机械性能和耐久性提高15%，最佳性能为10%。这显示了这些火山灰作为一种可行的部分水泥替代品的潜力，促进了埃塞俄比亚的可持续建筑实践。

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引用次数: 0

Assessment of ASR-induced development in concrete with natural and recycled reactive aggregates via resonant ultrasound spectroscopy coupled with imaging techniques 通过共振超声光谱结合成像技术评估天然和再生活性骨料混凝土中asr诱导的发展

CEMENT

Pub Date : 2025-11-29 DOI: 10.1016/j.cement.2025.100161

L.F.M. Sanchez , M. Griffa , A. Leemann

Numerous characterization techniques have been used to assess ASR-induced development (i.e., the formation of ASR products and cracks during expansion). Amongst those, scanning electron microscopy (SEM), coupled with energy dispersive X-ray spectroscopy (EDS), is a well-recognized technique enabling assessing the presence, morphology, and composition of ASR products. However, the correlation between ASR products' amounts and physicochemical features with induced damage (i.e., crack formation and impact on the mechanical performance of the affected concrete) via SEM is purely qualitative. Preliminary results showed that resonant ultrasound spectroscopy (RUS) could be a suitable technique to evaluate ASR-induced damage because it allows assessing the corresponding changes in the linear viscoelastic properties. Nonetheless, a systematic study fully demonstrating its potential to appraise ASR-induced expansion and deterioration, especially from ASR originating both from natural and from recycled aggregates, is still lacking in literature. This work aims to quantitatively appraise ASR-induced products and associated deterioration by the coupling of SEM-EDS and RUS, particularly a version thereof called SIngle MOde RUS (SIMORUS). Concrete mixtures incorporating highly reactive natural and recycled fine and coarse aggregates were cast and stored in conditions accelerating ASR development. At 4, 11, 16, 24 and 36 weeks, the samples were characterized by the abovementioned techniques. Quantifications of ASR-induced damage proxy parameters (i.e., Young’s, E, and shear, G, moduli), and the respective quality (Q-)factor, were performed over time. The results reported here suggest that SIMORUS is a promising technique to describe the impact of the ASR-induced development on the linear viscoelastic properties of an affected concrete. However, as shown, such an impact depends on the reactive aggregate type used in the mixture.

许多表征技术已被用于评估ASR诱导的发展（即，膨胀过程中ASR产物和裂纹的形成）。其中，扫描电子显微镜（SEM）和能量色散x射线光谱（EDS）是一种公认的技术，可以评估ASR产物的存在、形态和组成。然而，通过SEM， ASR产品的数量和物理化学特征与诱导损伤（即裂缝的形成和对受影响混凝土力学性能的影响）之间的关系纯粹是定性的。初步结果表明，共振超声光谱（RUS）可以作为一种评估asr损伤的合适技术，因为它可以评估相应的线性粘弹性变化。尽管如此，文献中仍然缺乏系统的研究来充分证明其评估ASR引起的扩张和恶化的潜力，特别是来自天然和再生骨料的ASR。这项工作旨在定量评估asr诱导的产物和通过SEM-EDS和RUS耦合的相关恶化，特别是称为单模RUS （SIMORUS）的版本。混合了高活性天然和再生细、粗骨料的混凝土在加速ASR发展的条件下浇筑和储存。在4、11、16、24和36周时，采用上述技术对样品进行表征。随着时间的推移，量化asr引起的损伤代理参数（即Young 's， E和剪切，G，模量）以及各自的质量（Q-）因子。本文报告的结果表明，SIMORUS是一种很有前途的技术，可以描述asr诱导的发展对受影响混凝土的线性粘弹性性能的影响。然而，如图所示，这种影响取决于混合物中使用的反应骨料类型。

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引用次数: 0

Alkali dissolution from aggregates and its effect on ASR expansion simulated by the use of alkali rock powder 用碱岩粉模拟集料的碱溶作用及其对ASR膨胀的影响

CEMENT

Pub Date : 2025-11-14 DOI: 10.1016/j.cement.2025.100160

Kannosuke Shiraishi , Kazuo Yamada , Takashi Kawakami , Yasutaka Sagawa , Soshiro Miyama

Concrete expansion due to an alkali-silica reaction (ASR) occurs when alkali ions (OH⁻) in the pore water react with silica minerals in reactive aggregates. To mitigate ASR expansion, the concentration of alkali ions determined primarily by the amount of alkali metals derived from cement has to be controlled. In addition to silica minerals, minerals in the aggregates containing alkali metals may also undergo reactions, resulting in the dissolution of alkali metals. It is considered that this release increases the OH⁻ concentration. This alkali metal dissolution reaction is referred to as alkali release. This phenomenon was investigated through the concrete prism test using a reactive chert aggregate and nepheline syenite (NS) powder, an alkali-rich rock. The results indicated that the addition of NS contributed to increased expansion over the storage period. At an NS addition of 5 % by mass of fine aggregate (NS5 %), the alkali dissolution from NS, estimated from the expansion, was 9.2 kg/m³, which closely matched the measured water-soluble alkali content of the concrete, 8.2 kg/m³. However, when the NS addition was increased to 10 % (NS10 %), the water-soluble alkali content increased to 11.2 kg/m³, yet the expansion rate remained unchanged compared to NS5 %. Thus, alkali dissolution beyond a certain threshold did not contribute further to expansion. Additionally, the alkali dissolution from NS, as evaluated using RILEM AAR-8, was considerably underestimated, with values of 0.13 kg/m³ for NS5 % and 0.25 kg/m³ for NS10 %.

当孔隙水中的碱离子（OH -）与反应性聚集体中的二氧化硅矿物反应时，会发生碱-二氧化硅反应（ASR）导致的混凝土膨胀。为了减缓ASR的膨胀，碱离子的浓度主要由水泥中碱金属的含量决定，必须加以控制。除了二氧化硅矿物外，含有碱金属的聚集体中的矿物也可能发生反应，导致碱金属溶解。这种释放被认为会增加OH -毒血症的浓度。这种碱金属溶解反应称为碱释放。利用活性燧石骨料和富碱岩石霞石正长岩（NS）粉，通过混凝土棱镜试验研究了这一现象。结果表明，在贮藏过程中，添加NS有助于增加膨胀。当细骨料（ns5%）的NS添加量为5%时，根据膨胀估计，NS的碱溶解量为9.2 kg/m³，与测量的混凝土水溶性碱含量8.2 kg/m³非常吻合。而当NS添加量增加到10% （ns10%）时，水溶性碱含量增加到11.2 kg/m³，但膨胀率与ns5%相比没有变化。因此，超过一定阈值的碱溶解不会进一步促进膨胀。此外，根据RILEM AAR-8的评估，NS的碱溶出度被大大低估了，ns5%的值为0.13 kg/m³，ns10%的值为0.25 kg/m³。

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引用次数: 0

Dissolution behaviour and mechanism of fly ash in acid activators 粉煤灰在酸性活化剂中的溶解行为及机理

CEMENT

Pub Date : 2025-10-27 DOI: 10.1016/j.cement.2025.100159

Mengxin Bu , Biqin Dong , Muhammad Riaz Ahmad , Yanshuai Wang

Clarifying the dissolution behaviour and mechanism of fly ash in acid activators is essential to understand the properties of fly ash-based silico-aluminophosphate geopolymer. This paper investigated the in-situ dissolution behaviour of fly ash (FA) in aluminium dihydrogen phosphate (MAP), phosphoric acid (PA), citric acid (CA), oxalic acid (OA), and tartaric acid (TA) using optical microscopy and electron probe microscopic analysis (EPMA). The phase and elemental changes before and after dissolution were further investigated using quantitative X-ray Diffraction (QXRD) and 2D-Fourier transform infrared (FTIR) spectrometry. In addition, the changes in dissolved elements were elucidated from a liquid phase perspective. The results showed that the capacity of each acid to dissolve FA was CA>MAP>PA>TA>OA. Ca-containing phases in FA were preferentially dissolved in all acids. The main contributor to FA dissolution in acid was the amorphous phase, and the SiOSi bond in quartz was more sensitive than other chemical bonds to acid. When FA was dissolved in OA and TA, new crystalline phases—calcium oxalate and calcium citrate—formed on the FA surface, inhibiting further dissolution.

弄清粉煤灰在酸性活化剂中的溶解行为和机理，对了解粉煤灰基硅铝磷酸酯地聚合物的性能具有重要意义。利用光学显微镜和电子探针显微镜（EPMA）研究了粉煤灰（FA）在磷酸二氢铝（MAP）、磷酸（PA）、柠檬酸（CA）、草酸（OA）和酒石酸（TA）中的原位溶解行为。利用定量x射线衍射（QXRD）和二维傅里叶变换红外光谱（FTIR）进一步研究了溶解前后的物相和元素变化。此外，还从液相角度分析了溶解元素的变化。结果表明，各酸对FA的溶解能力分别为CA>；MAP>PA>TA>；OA。FA中含钙相优先溶解于所有酸中。FA在酸中溶解的主要原因是无定形相，石英中的SiOSi键比其他化学键对酸更敏感。当FA溶解在OA和TA中时，FA表面会形成新的结晶相——草酸钙和柠檬酸钙，从而抑制了FA的进一步溶解。

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引用次数: 0

High-strength self-compacting alkali-activated concrete produced with fly ash and steel slag: rheological behavior and mixing rheology comparisons with a Portland cement concrete 粉煤灰和钢渣生产的高强度自密实碱活化混凝土：流变特性和与波特兰水泥混凝土的混合流变比较

CEMENT

Pub Date : 2025-09-14 DOI: 10.1016/j.cement.2025.100156

Lucas B.R. Araújo , Madson L. de Souza , Abcael R.S. Melo , Heloina N. Costa , Lucas F.A.L. Babadopulos , Antonio E.B. Cabral , Rafael G. Pileggi

The construction industry has recently seen a growing demand for sustainable materials. Alkali-activated binders (AAB) have emerged as a viable alternative to Portland cement-based materials. This study investigates the influences of the composition and mixing methods on the rheological and mechanical properties of an alkali-activated concrete (AAC) based on fly ash (FA) and steel slag (SS), compared to a reference Portland cement concrete (PCC) with equivalent volume fractions of aggregate and paste. Two mixing methods were examined: a free fall mixer and a planetary mixer that also functions as a rheometer. In the fresh state, the performance of concretes was assessed, focusing on rheological parameters such as mixing energy, maximum torque, and equivalent apparent viscosity indicator. In the hardened state, compressive strength tests were conducted. Pseudoplastic rheological model effectively described AAC behavior, while the Bingham model better characterized PCC. AAC demonstrated high passing ability and extended flow time, with flow behavior significantly influenced by the mixing process. Rheological analysis revealed that AAC required five times more mixing energy and exhibited greater equivalent apparent viscosity indicator compared to PCC. Additionally, AAC achieved higher compressive strength than PCC, which presented values from 34 to 43 MPa (PCC) depending on curing conditions. Thermal curing increased compressive strength by nearly 60 % at 28 days for AAC, from 48.6 MPa to 76.8 MPa. Furthermore, the mixing procedure influenced the fresh and hardened properties of both AAC and PCC, though PCC exhibited only minor variations. Mixing methods with higher energy input led to improved compressive strength.

最近，建筑行业对可持续材料的需求不断增长。碱活化粘合剂（AAB）已成为波特兰水泥基材料的可行替代品。本研究探讨了组成和搅拌方法对粉煤灰（FA）和钢渣（SS）碱活化混凝土（AAC）流变学和力学性能的影响，并与具有等体积分数骨料和膏体的参考波特兰水泥混凝土（PCC）进行了比较。研究了两种混合方法：一种是自由落体混合器，另一种是具有流变仪功能的行星混合器。在新鲜状态下，评估混凝土的性能，重点是流变参数，如搅拌能，最大扭矩和等效表观粘度指标。在硬化状态下进行抗压强度试验。假塑性流变模型能较好地描述AAC行为，Bingham模型能较好地表征PCC。AAC具有较高的通过能力和较长的流动时间，其流动特性受混合过程的影响较大。流变学分析表明，与PCC相比，AAC所需的混合能是PCC的5倍，其等效表观粘度指标也更高。此外，AAC的抗压强度高于PCC，根据养护条件的不同，其值为34 ~ 43 MPa （PCC）。热固化28天后，AAC的抗压强度提高了近60%，从48.6 MPa提高到76.8 MPa。此外，混合过程对AAC和PCC的新鲜和硬化性能都有影响，尽管PCC的变化很小。采用高能量输入的混合方法可提高材料的抗压强度。

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引用次数: 0

Hydration of portland cement and slag cement mixtures with insights on AFm phases and reaction mechanism 硅酸盐水泥和矿渣水泥混合料的水化及其AFm相和反应机理

CEMENT

Pub Date : 2025-08-21 DOI: 10.1016/j.cement.2025.100155

Mohsen Torabi , Peter C Taylor

Hydration of Portland cement + slag blends with different slag replacements at various hydration times has been studied. Findings from QXRD, TGA, ESEM(EDS) & NMR have provided us with insights into the hydration mechanisms and phase assemblage of cement and slag mixtures. Phase assemblage and quantification of the AFm phases has been made possible using the parallel beam X-ray diffraction and it was observed that AFm formation is favored in these blends in direct proportion with the slag level. In fact, AFm formation after pozzolanic reaction can be considered as one of the consumers of portlandite in portland cement+slag blends. Hydrocalumite has been observed to be present among the hydration phases of these blends at various hydration times and its concentration has been observed to increase with increasing slag replacement. The presence of this phase might have implications on the durability aspects of the resulting concrete. Furthermore, some chemical reactions during slag hydration as well as its interactions with hydration of clinker phases have also been proposed.

研究了不同矿渣替代量的硅酸盐水泥+矿渣在不同水化时间下的水化性能。QXRD， TGA， ESEM（EDS）和NMR的研究结果为我们提供了水泥和矿渣混合物水化机制和相组合的见解。利用平行束x射线衍射可以进行相组合和AFm相的量化，并观察到在这些混合料中，AFm的形成与炉渣水平成正比。事实上，在硅酸盐水泥+矿渣共混物中，火山灰反应后形成的AFm是硅酸盐的消耗者之一。在不同的水化时间，在这些混合物的水化相中观察到水矾土的存在，并观察到其浓度随着矿渣置换量的增加而增加。这一阶段的存在可能会对混凝土的耐久性产生影响。此外，还提出了渣水化过程中的一些化学反应及其与熟料相水化的相互作用。

引用次数: 0

Enhancing efficiency in evaluating alkali-silica reaction (ASR) damage: an automated approach to point-count microscopy 提高评估碱-硅反应（ASR）损伤的效率：点计数显微镜的自动化方法

CEMENT

Pub Date : 2025-07-27 DOI: 10.1016/j.cement.2025.100153

Cassandra Trottier , Laurent Ramos Cheret , Haoye Lu , Anthony Allard , Maia Fraser , Leandro F.M. Sanchez

The damage rating index (DRI) is a valuable microscopy tool for collecting and counting data on different types of concrete cracks, such as those associated with alkali-silica reaction (ASR) induced deterioration. Yet, the procedure presents drawbacks such as time consumption and variability linked to operator experience, which has sparked debates about the subjectivity of its outcomes. Embracing the forefront of technological advancements, this study explores the practicality of automating the DRI's data collection through artificial intelligence (AI) and machine learning. Like many image processing and analysis applications that use AI, the DRI is an object classification and segmentation task. This study represents a step forward in leveraging automation to enhance the objectivity and efficiency of ASR damage characterization in concrete through point-count microscopy, along with proposing a set of tools to evaluate the outcomes from the application’s perspective for more efficient training data selection. Results show that despite obtaining acceptable performance individually, where the detector-classifier performance was found to have an accuracy of 0.744, and the crack counter accuracy was 0.988, the current version of the proposed machine still displays high variability in detecting, classifying, and counting distinct crack types. Overall, the machine overestimates ASR-induced damage, which was further verified through the Chi-square goodness of fit test, indicating that further training and enhancement of the proposed machine are required.

损伤等级指数（DRI）是一种有价值的显微工具，用于收集和计数不同类型的混凝土裂缝数据，例如与碱-硅反应（ASR）引起的恶化有关的裂缝。然而，该方法存在一些缺点，如耗时和与操作人员经验相关的可变性，这引发了关于其结果主观性的争论。拥抱技术进步的前沿，本研究探索了通过人工智能（AI）和机器学习实现DRI数据收集自动化的可行性。像许多使用人工智能的图像处理和分析应用程序一样，DRI是一个对象分类和分割任务。这项研究代表了利用自动化技术通过点计数显微镜来提高混凝土ASR损伤表征的客观性和效率的一步，同时提出了一套工具来从应用程序的角度评估结果，以更有效地训练数据选择。结果表明，尽管单独获得了可接受的性能，其中检测器-分类器性能的准确率为0.744，裂纹计数器精度为0.988，但当前版本的机器在检测，分类和计数不同的裂纹类型方面仍然表现出很高的可变性。总的来说，机器高估了asr引起的损伤，卡方拟合优度检验进一步验证了这一点，表明需要进一步训练和增强所提出的机器。

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引用次数: 0

Condition assessment of pre-tensioning prestressed concrete sleepers distressed by internal swelling reactions (ISR) 内膨胀反应（ISR）下预张预应力混凝土枕木状态评价

CEMENT

Pub Date : 2025-07-23 DOI: 10.1016/j.cement.2025.100154

R. Medeiros , D.J. De Souza , L.F.M. Sanchez , A.C. Santos

Concrete sleepers worldwide have been affected by internal swelling reactions (ISR), primarily alkali-silica reaction (ASR) and internal sulfate attack (ISA). While numerous studies have focused on diagnosing ISR-affected sleepers, most emphasize identifying the cause rather than estimating the extent of deterioration, which is critical for informed decision-making. This study presents a comprehensive condition assessment of concrete sleepers displaying numerous ages and environmental exposure conditions through visual inspection (i.e., crack measurements) followed by the implementation of the multi-level assessment protocol, composed of microscopic (i.e., damage rating index-DRI) and mechanical (i.e., stiffness damage test-SDT) testing procedures. Results evidenced the multi-level protocol efficiency in estimating the cause(s) (i.e., ASR+ISA), further confirmed through SEM-EDS analysis, and quantifying the deterioration extent. These findings reveal gaps in current specification to prevent ISR damage in new sleepers and the importance of considering environmental conditions in condition assessment of existing sleepers, demonstrating an urgent need to review specifications/protocols.

混凝土轨枕在世界范围内受到内部膨胀反应（ISR），主要是碱-硅反应（ASR）和内部硫酸盐侵蚀（ISA）的影响。虽然许多研究都集中在诊断受isr影响的睡眠者，但大多数研究都强调确定原因，而不是估计恶化的程度，这对明智的决策至关重要。本研究通过目视检查（即裂缝测量）对混凝土枕木进行了全面的状态评估，显示了许多年龄和环境暴露条件，随后实施了多层次评估方案，由微观（即损伤等级指数- dri）和力学（即刚度损伤测试- sdt）测试程序组成。结果证明了多级协议在估计原因（即ASR+ISA）方面的效率，并通过SEM-EDS分析进一步证实，并量化了恶化程度。这些发现揭示了当前规范在防止新枕木的ISR损伤方面存在的差距，以及在对现有枕木进行状态评估时考虑环境条件的重要性，表明迫切需要审查规范/协议。

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引用次数: 0

Non-aging basic creep of alkali-activated slag concrete: Multiscale characterization and modeling 碱活化矿渣混凝土的非老化基本徐变：多尺度表征与建模

CEMENT

Pub Date : 2025-07-20 DOI: 10.1016/j.cement.2025.100151

Richard Caron , Ravi A. Patel , Andreas Bogner , Frank Dehn

This study focuses on a multiscale characterization of basic creep behavior of two AAS creep mixes with high (hS) and low (lS) slag content, loaded at 28 days. Nano-indentation tests are performed to investigate creep properties of individual phases and classical creep tests to analyze the creep behavior of concrete. An analytical multiscale micromechanics-based model is applied to downscale creep properties of the reaction product foam at nano-scale to compare it with results from nano-indentation. The creep at nanoscale of reaction product foam is modeled with a compliance function considering only deviatoric component consisting of Kelvin–Voigt chain for short term behavior and logarithmic function to account for long-term behavior. Comparing downscaled compliance with creep modulus measured from nano-indentation it is concluded that nano-indentation captures long-term behavior of reaction product foam. In terms of two mix tested, while at nano-scale mix hS has a higher creep modulus, presence of more capillary porosity and micro-cracks counteracts this and as a result concrete with mix hS shows higher creep. The creep modulus of AAS product foam obtained from nano-indentation is significantly lower compared to the OPC products. Additionally, higher amount of gel water and fewer crystalline secondary products could explain higher creep observed for AAS concrete compared to OPC concrete.

本研究的重点是对两种高（hS）和低（lS）渣含量的AAS蠕变混合料在加载28天时的基本蠕变行为进行多尺度表征。采用纳米压痕试验研究了混凝土各相的徐变特性，采用经典徐变试验分析了混凝土的徐变特性。采用多尺度细观力学模型分析了反应产物泡沫在纳米尺度下的蠕变特性，并与纳米压痕结果进行了比较。用仅考虑由Kelvin-Voigt链组成的偏差分量的柔度函数和考虑长期行为的对数函数来模拟反应产物泡沫在纳米尺度上的蠕变。通过对比纳米压痕测量的蠕变模量和缩尺顺应性，得出纳米压痕能够捕获反应产物泡沫的长期行为的结论。两种配合比的试验结果表明，在纳米尺度下，hS配合比具有较高的徐变模量，但更多的毛管孔隙和微裂缝的存在抵消了这一作用，使得hS配合比混凝土表现出更高的徐变模量。纳米压痕制备的AAS产品泡沫的蠕变模量明显低于OPC产品。此外，较高的凝胶水量和较少的结晶二次产物可以解释AAS混凝土比OPC混凝土观察到的更高的徐变。

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引用次数: 0