CEMENT

Pub Date : 2024-12-01 Epub Date: 2024-09-21 DOI: 10.1016/j.cement.2024.100115

Yujia Min , Erin Stewartson , Prannoy Suraneni , Christopher R. Shearer , R. Doug Hooton , Lisa E. Burris

This manuscript presents two novel methods of evaluating the adsorption of air-entraining admixtures (AEAs) by coal ashes used in cementitious mixtures. A developed three-phase equilibrium (TPE) method measures fly ash adsorption capacity accounting for carbon adsorption, Ca²⁺ interactions with AEA, and the equilibrium between the two. A fluorescence-based method (FBM) was also developed, utilizing a non-ionic NP-10 surfactant as a representative for AEA. This study verifies the applicability and accuracy of the TPE and FBM methods using seven class C and F coal ashes with a wide range of loss on ignition values, varying from 0.2 to 15.6 %, and three commercial AEAs. Verified with foam index test results, the TPE method was applicable to all tested AEAs and coal ashes. The results were consistent between the FBM and TPE methods when comparing rosin- and fatty acid-based AEAs, but less consistent when using a sulfonate-based AEA. These findings help us understand the applicability and limitations of the TPE and FBM methods and provide two methods for quantifying adsorption in fly ash samples.

本手稿介绍了两种评估水泥基混合物中使用的煤灰对引气外加剂（AEA）吸附情况的新方法。开发的三相平衡法 (TPE) 可测量粉煤灰的吸附能力，其中包括碳吸附、Ca2+ 与 AEA 的相互作用以及两者之间的平衡。利用非离子 NP-10 表面活性剂作为 AEA 的代表，还开发了一种基于荧光的方法 (FBM)。本研究使用七种 C 级和 F 级煤灰（着火损失值范围从 0.2% 到 15.6% 不等）以及三种商用 AEA，验证了 TPE 和 FBM 方法的适用性和准确性。经泡沫指数测试结果验证，TPE 方法适用于所有测试的 AEA 和煤灰。在比较松香基和脂肪酸基 AEA 时，FBM 法和 TPE 法的结果是一致的，但在使用磺酸盐基 AEA 时，结果则不太一致。这些发现有助于我们了解 TPE 和 FBM 方法的适用性和局限性，并为量化粉煤灰样品中的吸附性提供了两种方法。

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引用次数: 0

Biomass ash (BA) waste as an activator to produce carbon-negative cement 生物质灰（BA）废料作为生产负碳水泥的活化剂

CEMENT

Pub Date : 2024-12-01 Epub Date: 2024-09-18 DOI: 10.1016/j.cement.2024.100112

Zehao Lei, Sara Pavia

The use of biomass, as a renewable energy source, to run heating and power plants is propelled by sustainable European policy. Olive is an important resource in Mediterranean countries. The residues from the extraction of olive oil are used as biomass, either to produce the oil or to generate heat or electricity. The disposal of ash residue poses an important burden. This study uses olive pit bottom ash waste (OBA) to produce carbon-negative cement. The OBA is mixed with waste GGBS (GGBS), and neither calcination nor thermal curing are used to lower environmental impact.

The cements produced contain up to 60 %OBA and have a carbon sequestration capacity up to -97.45 kg CO₂e/m³. An optimum mix with 40 %OBA is developed (using auxiliary activator), with compressive strength of 36–44 MPa and a carbon sequestration capacity of 40–45 kg CO₂/m³. A modified loss on ignition test is proposed to evaluate the embodied carbon of biomass ash.

The OBA's main chemical constituents: K₂O and CaO, afford outstanding activation and alkalinity to release Ca²⁺ Si⁴⁺ and Al³⁺ from GGBS to form calcite, hydrotalcite, C-(A)-S-H and amorphous cements. Using sodium carbonate (NC) and lime as supplementary activators enhanced the mechanical properties of the cements and slightly changed their composition and microstructure. NC is the most efficient activator, it increased dissolution, and produced a denser and stronger cement with higher Si and K concentration that includes gaylussite, N-A-S-H and C(K)-A-S-H. Pre-dissolving the NC prior to mixing increases the activator's efficiency, producing less calcite cement for the same amount of NC. By adding 4 % pre-dissolved NC, the compressive strength increased by 138.76 % (compared to OBA-GGBS mortar without auxiliary activators) and 113.94 % compared to the material with NC in powder form.

生物质能作为一种可再生能源，在欧洲可持续发展政策的推动下用于供热和发电厂。橄榄是地中海国家的重要资源。榨取橄榄油的残渣被用作生物质能源，既可以用来生产橄榄油，也可以用来供热或发电。灰渣的处理是一项重要负担。本研究利用橄榄油坑底灰渣（OBA）生产负碳水泥。OBA 与废弃 GGBS（GGBS）混合，既不煅烧也不热固化，以降低对环境的影响。所生产的水泥含有高达 60% 的 OBA，固碳能力高达 -97.45 kg CO2e/m3。开发出一种含 40 %OBA 的最佳混合物（使用辅助活化剂），其抗压强度为 36-44 兆帕，固碳能力为 40-45 千克二氧化碳/立方米。提出了一种改进的点火损失试验来评估生物质灰烬的含碳量：OBA 的主要化学成分：K2O 和 CaO 具有出色的活化和碱度，可从 GGBS 中释放 Ca2+ Si4+ 和 Al3+，形成方解石、水滑石、C-(A)-S-H 和无定形水泥。使用碳酸钠（NC）和石灰作为辅助活化剂可提高水泥的机械性能，并轻微改变水泥的成分和微观结构。碳酸钠是最有效的活化剂，它能增加溶解度，并产生一种更致密、更坚固的水泥，其中硅和钾的浓度更高，包括基质、N-A-S-H 和 C（K）-A-S-H。在混合前预溶解 NC 可提高活化剂的效率，在使用相同数量 NC 的情况下，可生产出更少的方解石水泥。通过添加 4% 的预溶解 NC，抗压强度提高了 138.76%（与不添加辅助活化剂的 OBA-GGBS 砂浆相比），与添加粉末状 NC 的材料相比，抗压强度提高了 113.94%。

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引用次数: 0

Co-calcination to produce a synergistic blend of bauxite residue and low-grade kaolinitic clay for use as a supplementary cementitious material 通过共煅烧产生铝矾土渣和低品位高岭土的协同混合物，用作胶凝补充材料

CEMENT

Pub Date : 2024-12-01 Epub Date: 2024-11-15 DOI: 10.1016/j.cement.2024.100122

Arne Peys , Athina Preveniou , David Konlechner , Guilherme Rubio , Maria Georgiades , Rupert J. Myers , Natalia Pires Martins , Efthymios Balomenos , Panagiotis Davris , Ruben Snellings , Ken Evans

New sources of reactive supplementary cementitious materials (SCMs) are essential to help the cement industry to further lower CO₂ emissions. A co-calcination process in which bauxite residue (BR) is mixed with kaolinitic clay before calcination can deliver such SCM. The main novelty of the work discussed here is that acceptable reactivity as a SCM can be reached when co-calcining the BR with clays having only 40 wt% of kaolinite. The use of such low-grade kaolinitic clay greater increases the process economics and therefore likely increases overall feasibility. A high inherent reactivity of the desilication products present in the BR is the cause of this ability of using low-grade kaolinitic clays. Cement mortars were made with 30 wt% replacement of CEM I, which showed adequate strength at 28 days and increased strength in comparison with calcined clays or other SCMs in the literature at early age (2–7 days). A wide process temperature window with relatively constant reactivity was observed, but a range of 700–750 °C is recommended for process stability. In addition, a life-cycle assessment underlines that at these conditions a sufficiently low embodied CO₂ relative to Portland clinker production is obtained.

要帮助水泥行业进一步降低二氧化碳排放量，必须要有新的活性胶凝补充材料（SCM）来源。矾土渣（BR）在煅烧前与高岭土混合的共煅烧工艺可以提供这种 SCM。本文所讨论的工作的主要新颖之处在于，当铝矾土渣与仅含 40 wt% 高岭石的粘土进行共煅烧时，可以达到可接受的反应活性，作为一种 SCM。使用这种低品位的高岭土可以提高工艺的经济性，从而提高整体可行性。BR 中存在的脱硅产物的高固有反应性是使用低级高岭土的原因。用 30 wt%的 CEM I 替代物制作水泥砂浆，28 天时强度足够，与文献中的煅烧粘土或其他单质材料相比，在早期龄期（2-7 天）强度更高。观察到的工艺温度窗口较宽，反应活性相对稳定，但为了工艺稳定性，建议温度范围为 700-750 °C。此外，生命周期评估强调，在这些条件下，相对于波特兰熟料生产，二氧化碳的体现量足够低。

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引用次数: 0

Downstream processing of End-of-Life concrete for the recovery of high-quality cementitious fractions 对报废混凝土进行下游处理以回收优质胶凝组分

CEMENT

Pub Date : 2024-12-01 Epub Date: 2024-11-06 DOI: 10.1016/j.cement.2024.100121

A.T.M. Alberda van Ekenstein , H.M. Jonkers , M. Ottelé

The clinker in cement largely determines the environmental footprint of concrete. Therefore, concrete recycling should focus on retrieving high-quality cementitious fractions to replace clinker. This requires a shift from current traditional recycling techniques towards innovative recycling methods, enabling recovery of not only clean secondary aggregates, but also residual cementitious fines (RCF), potentially eliminating the carbon dioxide emissions associated with them. The production and upcycling of RCF offer new implementation routes that were previously deemed unfeasible. However, the properties of RCF may vary based on their origin, affecting their replacement and upcycling potential. Consequently, assessing the original concrete quality, with a focus on the binder type, before demolition is important. A handheld x-ray fluorescence technique appears promising for this purpose. To achieve effective separation of clean secondary aggregates from the original cementitious content, innovative crushing and separation techniques are needed. Additionally, electrostatic separation shows significant research potential for further optimizing RCF.

水泥中的熟料在很大程度上决定了混凝土的环境足迹。因此，混凝土回收应侧重于回收高质量的胶凝组分来替代熟料。这就要求从目前的传统回收技术转向创新的回收方法，不仅能够回收干净的二次骨料，还能回收残余胶凝细粒（RCF），从而消除与之相关的二氧化碳排放。RCF 的生产和升级再循环提供了新的实施途径，这在以前被认为是不可行的。然而，RCF 的特性可能因其来源而异，从而影响其替代和再循环潜力。因此，在拆除之前评估原始混凝土质量（重点是粘合剂类型）非常重要。手持式 X 射线荧光技术在这方面似乎大有可为。为了从原始胶凝成分中有效分离出干净的二次集料，需要采用创新的破碎和分离技术。此外，静电分离技术在进一步优化 RCF 方面也具有巨大的研究潜力。

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引用次数: 0

Workability, compressive strength, and efflorescence characteristics of one-part mix alkali-activated circulating fluidised bed combustion fly ash-based mortars 单组分碱活化循环流化床燃烧粉煤灰基砂浆的和易性、抗压强度和发光特性

CEMENT

Pub Date : 2024-12-01 Epub Date: 2024-12-03 DOI: 10.1016/j.cement.2024.100123

Jason Shun Fui Pei , Chung Siung Choo , Deni Shidqi Khaerudini , Sing Muk Ng , Dominic Ek Leong Ong , Melvina Tan , Jaka Sunarso

In this study, one-part alkali-activated mortars are formulated using circulating fluidised bed combustion (CFBC) fly ash, derived from lignite (brown coal) combustion, as the precursor, and sodium hydroxide (NaOH) and sodium metasilicate (Na₂SiO₃) as the solid activators. Experimental findings indicate that an increase in solid activator-to-precursor ratio correlates with improved workability and compressive strength of the mortars. The influence of Na₂SiO₃-to-NaOH ratio on the compressive strength of the mortars is apparent only in mixes with a high solid activator-to-precursor ratio of 0.4 and 0.5, indicating its relatively lesser significance compared to the solid activator-to-precursor ratio. The mechanism through which an increase in the solid activator-to-precursor ratio improves the compressive strength of the mortars is elucidated using attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy. The results indicate that increasing the solid activator-to-precursor ratio enhances the degree of alkali-activation for fly ash, thereby improving the compressive strength with increasing solid activator-to-precursor ratio.

本研究以褐煤（褐煤）燃烧产生的循环流化床燃烧（CFBC）粉煤灰为前驱体，氢氧化钠（NaOH）和偏硅酸钠（Na2SiO3）为固体活化剂，配制了一组分碱活化砂浆。实验结果表明，固体激发剂与前驱体比的增加与砂浆的和易性和抗压强度的提高有关。na2sio3 - naoh比对砂浆抗压强度的影响仅在固体激发剂与前驱体比（0.4和0.5）较高的混合料中表现出来，与固体激发剂与前驱体比相比，其影响相对较小。利用衰减全反射-傅里叶变换红外（ATR-FTIR）光谱分析了固体激发剂与前驱体比增加提高砂浆抗压强度的机理。结果表明：提高固体激发剂与前驱体的比例可以提高粉煤灰的碱活化程度，从而提高粉煤灰的抗压强度。

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引用次数: 0

Accelerating effect of low replacements of carbonaceous materials in cement paste and mortar 水泥浆和砂浆中碳质材料低替代率的加速效应

CEMENT

Pub Date : 2024-12-01 Epub Date: 2024-09-30 DOI: 10.1016/j.cement.2024.100118

Victor Brial, Thomas Duplessis, Claudiane M. Ouellet-Plamondon

This study investigated the effect of incorporating small amounts of carbonaceous materials in cement paste and mortar systems at a low dosage. The materials studied include industrial graphite, natural graphite, carbon black, activated charcoal, and decolorized charcoal. The effect of this material on cement hydration through different techniques such as compressive strength mortar, TGA, SEM, isothermal calorimetry, rheology, and calcium isotherm adsoprtion. These tests studied the influence of carbonaceous materials’ properties on cement hydration. With the exception of industrial graphite G1, the carbonaceous materials showed an acceleration of setting after 1 day by favoring the nucleation of hydrates, reducing the porosity, and improving the mechanical properties. On the other hand, traces of this acceleration are no longer visible beyond 28 days. The accelerating effect of different carbons sources appears to be less dependent of crystallinity, mineralogy, or particle size, but rather on surface chemistry and the quality of particle dispersion.

本研究调查了在水泥浆和砂浆系统中加入少量低剂量碳质材料的效果。研究的材料包括工业石墨、天然石墨、炭黑、活性炭和脱色炭。通过不同的技术，如抗压强度砂浆、热重分析、扫描电镜、等温量热、流变学和钙等温吸附等，研究了这些材料对水泥水化的影响。这些测试研究了碳质材料的特性对水泥水化的影响。除工业石墨 G1 外，其他碳质材料在 1 天后通过促进水化物成核、降低孔隙率和改善机械性能，显示出加速凝结的作用。另一方面，这种加速的痕迹在 28 天后就不再明显。不同碳源的加速效果似乎与结晶度、矿物学或颗粒大小的关系不大，而是取决于表面化学和颗粒分散的质量。

引用次数: 0

The impact of relative humidity on the nanoindentation relaxation in calcium silicate hydrates 相对湿度对硅酸钙水合物纳米压痕松弛的影响

CEMENT

Pub Date : 2024-12-01 Epub Date: 2024-10-16 DOI: 10.1016/j.cement.2024.100120

Zhao Chen , Jessy Frech-Baronet , Hang Tran , Luca Sorelli

Despite extensive research efforts, understanding the time-dependent behavior of concrete remains an enigma due to the complex nature of cement microstructure. In this study, the statistical nanoindentation was employed to investigate the influence of relative humidity (RH) on the relaxation behavior of calcium silicate hydrates (C-S-H) in a cement paste. Our experiments, performed at RH levels of 33 % and 86 %, revealed significant enhancements in both the indentation modulus and hardness of the C-S-H as RH increased. Remarkably, the internal water exerted a significant influence on the asymptotic relaxation behavior, displaying a clear power-law fashion. Further analysis identified the presence of short- and long-term viscoelastic behaviors within the C-S-H, distinguished by a transition observed within the initial seconds. These findings advance the understanding of nanoscale mechanisms driving concrete creep under different humidity conditions.

尽管进行了大量研究，但由于水泥微观结构的复杂性，对混凝土随时间变化的行为的理解仍然是一个谜。本研究采用统计纳米压痕法研究相对湿度（RH）对水泥浆中硅酸钙水合物（C-S-H）松弛行为的影响。我们在相对湿度为 33% 和 86% 的条件下进行的实验表明，随着相对湿度的增加，C-S-H 的压痕模量和硬度都有显著提高。值得注意的是，内部水分对渐进松弛行为产生了重大影响，呈现出明显的幂律模式。进一步分析发现，C-S-H 中存在短期和长期粘弹性行为，并在最初几秒钟内出现了过渡。这些发现加深了人们对不同湿度条件下混凝土徐变的纳米级驱动机制的理解。

引用次数: 0

Low-grade fly ash in portland cement blends: A decoupling approach to evaluate reactivity and hydration effects 硅酸盐水泥掺合料中的低标号粉煤灰：评估反应性和水化效应的解耦方法

CEMENT

Pub Date : 2024-12-01 Epub Date: 2024-10-04 DOI: 10.1016/j.cement.2024.100119

Qingxu Jin , Wenyu Liao , Xiaoqiang Ni , Hongyan Ma

Fly ash with low glass content is often prohibited from use in concrete due to the low reactivity and/or the inclusion of contaminants. However, the scarcity of high-quality fly ash promotes the evaluation of the feasibility of using fly ash with low glass content (e.g., low-grade fly ash) in concrete. This study proposes a decoupling method to quantitatively estimate the degree of reaction of fly ash with extremely low glass content, which partially replaces cement, and the degree of hydration of the hosting cement, simultaneously. The estimation is derived from the contents of calcium hydroxide and chemically bonded water in hydrated binary cement pastes, which can be determined by thermogravimetric analysis-based experiments and theoretically validated stoichiometric parameters. The results exhibit that the fly ash tends to retard the early-age hydration of cement but promotes its later-age hydration, resulting in a higher ultimate degree of reaction of cement than the reference paste. The microstructural and porosity evaluation shows that the fly ash, though has relatively low degrees of reaction due to its low glass content, can result in a more tortuous pore network of the hydrated pastes, which could be potentially more resistant to the penetration of water and aggressive chemicals.

玻璃含量低的粉煤灰由于反应活性低和/或含有污染物，通常被禁止用于混凝土中。然而，优质粉煤灰的稀缺促进了对在混凝土中使用低玻璃含量粉煤灰（如低等级粉煤灰）可行性的评估。本研究提出了一种解耦方法，可同时定量估算部分取代水泥的玻璃含量极低的粉煤灰的反应程度和宿主水泥的水化程度。估算值来自水化二元水泥浆中氢氧化钙和化学键水的含量，可通过基于热重分析的实验和理论验证的化学计量参数确定。结果表明，粉煤灰往往会延缓水泥的早期水化，但会促进其后期水化，从而使水泥的最终反应度高于参考浆体。微观结构和孔隙率评估结果表明，粉煤灰虽然因其玻璃含量低而反应度相对较低，但却能使水化浆料的孔隙网络更加曲折，从而可能更能抵御水和侵蚀性化学品的渗透。

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引用次数: 0

Comparison of eggshell powder blended cementitious materials with ASTM Type IL cement-based materials 蛋壳粉混合胶凝材料与 ASTM IL 型水泥基材料的比较

CEMENT

Pub Date : 2024-09-01 Epub Date: 2024-07-04 DOI: 10.1016/j.cement.2024.100109

M. Shariful Islam, Benjamin J. Mohr

The present study explores the potential of producing an alternative ASTM Type IL portland-limestone cement (PLC) using up to 20 % eggshell powder (ESP) by mass as crushed ESP is similar in chemical composition to limestone. To this aim, the hydration, durability, and mechanical properties of the ESP blended cementitious system (using ASTM Type I/II portland cement) are compared to a commercially available ASTM Type IL cement system containing approximately 10 % limestone. ESP was prepared by milling for 3 h upon drying. Characterization of the ESP was done by x-ray diffraction for phase analysis, scanning electron microscopy for microstructural observation, and laser diffraction analysis for particle size distribution. A range of experimental tests were undertaken on both the ASTM Type I/II cement replaced with ESP and the ASTM Type IL systems. Results revealed that the utilization of up to 20 % ESP enhanced the heat of hydration secondary peak (C₃A) by increasing the aluminate phase kinetics in the blended system at a favorable pH pore solution. Also, an accelerating effect on the setting time (increased by 20–100 mins) was observed for ESP samples. Chemical shrinkage, compressive strength, and degree of hydration were similar between the ESP and PLC samples. Results also revealed that ESP particles were relatively more effective in minimizing drying shrinkage by 20–35 %, which is attributed to possible internal curing effects. Overall, 10 % ESP blended with ASTM Type I/II cementitious system was similar to the 10 % limestone containing PLC system and could be used as waste material in producing an alternative ASTM Type IL cement.

本研究探讨了使用高达 20% 的蛋壳粉（ESP）（按重量计）生产 ASTM IL 型波特兰-石灰石水泥（PLC）替代品的可能性，因为碎蛋壳粉的化学成分与石灰石相似。为此，我们将 ESP 混合胶凝体系（使用 ASTM I/II 型硅酸盐水泥）的水化、耐久性和机械性能与含有约 10% 石灰石的市售 ASTM IL 型水泥体系进行了比较。ESP 是通过在干燥后研磨 3 小时制备的。通过 X 射线衍射进行相分析，通过扫描电子显微镜观察微观结构，通过激光衍射分析粒度分布，从而确定 ESP 的特性。对用 ESP 替代的 ASTM I/II 型水泥和 ASTM IL 型系统进行了一系列实验测试。结果表明，在 pH 值较好的孔隙溶液中，使用多达 20% 的 ESP 可通过增加混合体系中的铝酸盐相动力学来提高水化热次生峰 (C3A)。此外，还观察到 ESP 样品对凝结时间有加速作用（增加 20-100 分钟）。ESP 和 PLC 样品的化学收缩率、抗压强度和水化程度相似。结果还显示，ESP 颗粒在减少 20%-35% 干燥收缩方面相对更有效，这可能是由于内部固化效应造成的。总之，掺入 10 % ESP 的 ASTM I/II 类胶凝体系与含 10 % 石灰石的 PLC 体系相似，可用作生产替代 ASTM IL 类水泥的废料。

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引用次数: 0

Estimation of cement paste stiffness and UHPC elastic modulus through measured phase-property upscaling 通过测量的相位特性放大估算水泥浆刚度和超高强度混凝土弹性模量

CEMENT

Pub Date : 2024-09-01 Epub Date: 2024-08-09 DOI: 10.1016/j.cement.2024.100110

Charissa Puttbach, Gary S. Prinz, Cameron D. Murray

The elastic stiffness of bulk concrete materials results from the complex interaction of aggregates, voids, and hydrated cement (which can have multiple hardened phases at multiple length scales). Given the complexities associated with understanding the arrangement of these particles within bulk concrete volumes, estimations for elastic modulus often rely on empirical correlations with unit weight and compressive strength. Such estimations are inherently scale-dependent and fail to capture variability in mix designs, particularly the variability found in specialty concrete mixes. To develop a scale-independent method for estimating elastic modulus from mix-design volume fraction information, this study explores a novel bottom-up approach using cement paste phase stiffness values determined through micro-mechanical experimentation and randomized Monte-Carlo spring arrangement simulations. Statistical representations of cement paste phase stiffness distributions and bulk volume fraction data are combined to provide estimations for elastic stiffness in both the composite cement paste and bulk concrete containing fine aggregate and fibers. Resulting a priori estimations of UHPC cement paste stiffness from the micro-mechanical upscaling simulations were within 4% of measured values (based on mix-design and void volume fraction information alone) for a selected sample of mix proportions. When applied to the two UHPC mixes containing fibers and fine aggregate, upscaling simulations consistently overpredicted the measured elastic modulus, likely due to the aggregate-cement interfacial transition zone (ITZ) properties that were not captured in the micro-mechanical testing.

大体积混凝土材料的弹性刚度是由骨料、空隙和水化水泥（在多个长度尺度上可能有多个硬化阶段）的复杂相互作用产生的。由于了解这些颗粒在大体积混凝土中的排列很复杂，弹性模量的估算通常依赖于与单位重量和抗压强度的经验相关性。这种估算方法本质上依赖于规模，无法捕捉混合设计中的变化，特别是特种混凝土混合料中的变化。为了开发一种与规模无关的方法，从混合设计体积分数信息中估算弹性模量，本研究探索了一种自下而上的新方法，使用通过微机械实验和随机蒙特卡洛弹簧布置模拟确定的水泥浆相刚度值。水泥浆相刚度分布的统计表示法与大体积分数数据相结合，对复合水泥浆和含有细骨料和纤维的大体积混凝土的弹性刚度进行了估算。在选定的混合比例样本中，通过微观机械放大模拟对超高强度混凝土水泥浆刚度的先验估算结果与测量值（仅基于混合设计和空隙体积分数信息）的误差在 4% 以内。当应用于含有纤维和细集料的两种 UHPC 混合料时，升级模拟始终高估了测量弹性模量，这可能是由于集料-水泥界面过渡区 (ITZ) 的特性未在微观力学测试中捕捉到。

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引用次数: 0

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