Construction and Building Materials最新文献_第10页

Study on size effect in small-diameter ultra-high-performance concrete cylinders across strength classes 小直径超高性能混凝土柱体跨强度等级尺寸效应研究

IF 8 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Construction and Building Materials

Pub Date : 2026-01-26 DOI: 10.1016/j.conbuildmat.2026.145277

Mingyi Zhang , Dingyi Yang , Xiang Mao , Zhenxiang Jie , Junbao Yu

Ultra-high-performance concrete (UHPC), owing to its outstanding mechanical strength and durability, is increasingly used in structural engineering. This study systematically investigates the size effect of small UHPC cylinders under uniaxial compression. The experimental program covers five strength classes (UC120–UC200), three diameters (30, 40 and 50 mm), and aspect ratios H/D = 1.0–3.0. The influence of strength class, specimen size and aspect ratio on compressive strength is quantified by the size-effect degree (η) and the size-effect conversion coefficient (C). Test results show that compressive strength decreases with increasing specimen size, with this reduction amplified at higher aspect ratios; small-diameter specimens (especially 30 mm) exhibit the greatest size sensitivity. Bažant’s size effect law (SEL) is employed to fit the data across strength classes and specimen sizes and to derive strength conversion relationships. Finite-element simulations in ABAQUS reproduce the observed failure patterns and confirm the dependence of the size effect on aspect ratio. The proposed size-effect indices, SEL-based laws and conversion coefficients provide a practical basis for converting strengths between UHPC cylinders of different sizes and for calibrating structural design using small-scale specimens.

超高性能混凝土（UHPC）由于其优异的机械强度和耐久性，在结构工程中得到越来越多的应用。本研究系统地研究了单轴压缩条件下UHPC小型圆柱体的尺寸效应。实验方案包括五个强度等级（UC120-UC200），三种直径（30、40和50 mm），长径比H/D = 1.0-3.0。强度等级、试样尺寸和长径比对抗压强度的影响由尺寸效应程度（η）和尺寸效应转换系数(C)来量化。试验结果表明，抗压强度随试件尺寸的增大而减小，且在高纵横比下减小幅度更大；小直径试样（尤其是30 mm）表现出最大的尺寸敏感性。采用Bažant的尺寸效应定律（SEL）来拟合不同强度类别和试件尺寸的数据，并推导强度转换关系。ABAQUS中的有限元模拟再现了观察到的破坏模式，并证实了尺寸效应与纵横比的相关性。提出的尺寸效应指标、基于sel的规律和转换系数，为不同尺寸的超高强度混凝土柱体之间的强度转换和采用小尺度试件的结构设计标定提供了实践依据。

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引用次数: 0

Wood bottom ash as sand replacement in concrete: Mechanical properties and prediction of durability 木底灰在混凝土中的替代砂：力学性能和耐久性预测

IF 8 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Construction and Building Materials

Pub Date : 2026-01-26 DOI: 10.1016/j.conbuildmat.2026.145415

Anders Hedegaard Jensen , Lisbeth M. Ottosen , Carola Edvardsen

The global issue of sand shortages require research in alternatives to natural sand as fine aggregate in concrete. Bottom ash from fluidized bed boilers are promising candidates for application as a partial substitution. This study investigates the mechanical properties of concrete with 0 %, 25 % and 50 % wood bottom ash substituting natural sand. Three wood bottom ashes from Denmark were tested: two from a circulating fluidized bed (CFB) boiler, and one from a bubbling fluidized bed (BFB) boiler. Characterization of the ashes was done by XRF, XRD and X-ray tomography, as well as measurements of density and absorption. Concrete cylinders are tested for their compressive strength and E-modulus at 14, 28 and 180 maturity days. To make an estimation of the durability, the electrical resistivity was measured on the specimens before each mechanical test. Characterization of the ash indicated limited reactivity, despite a high content of SiO₂. X-ray analysis showed that many of the particles had developed cracks and internal pores during the combustion process. The effect on the mechanical properties of the concrete appeared to be minimal, as the compressive strength of the specimens with CFB and BFB was increased compared to the reference mix with 100 % natural sand. The exception was the mixes with 25 % and 50 % BFB ash, which developed cracks between the tests at 28 days and 180 maturity days. The E-modulus of concrete decreased with higher ash contents.

沙子短缺的全球性问题需要研究天然沙子作为混凝土细骨料的替代品。流化床锅炉的底灰是一种很有前途的部分替代材料。研究了0 %、25 %和50 %木底灰替代天然砂的混凝土力学性能。对来自丹麦的三种木底灰进行了测试：两种来自循环流化床（CFB）锅炉，一种来自鼓泡流化床（BFB）锅炉。通过XRF， XRD和x射线断层扫描以及密度和吸收测量对灰烬进行了表征。对混凝土柱体在14、28和180成熟日的抗压强度和e模量进行了测试。在每次力学试验前，对试件的电阻率进行了测量，以估计其耐久性。灰分的表征表明，尽管SiO2含量很高，但反应性有限。x射线分析表明，许多颗粒在燃烧过程中产生了裂纹和内部孔隙。对混凝土力学性能的影响似乎很小，因为与含有100% %天然砂的参考混合料相比，CFB和BFB的试件的抗压强度有所增加。唯一的例外是含有25% %和50% % BFB灰分的混合料，在28天和180天的试验期间出现裂缝。混凝土e模量随灰分的增加而降低。

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引用次数: 0

Experimental study on the mechanical and fire resistance properties of sprayed ultra-high-performance concrete (SUHPC) under different polypropylene fiber content 不同聚丙烯纤维掺量下喷涂超高性能混凝土（SUHPC）力学性能和耐火性能的试验研究

IF 8 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Construction and Building Materials

Pub Date : 2026-01-26 DOI: 10.1016/j.conbuildmat.2026.145405

Tao Chen , Huai-Na Wu , Min Wang , De-Sai Guo , Man Yu , Xin-Yin Wu , Ren-Peng Chen

The dense structure of ultra-high-performance concrete(UHPC) makes it susceptible to spalling in high-temperature environments. Although spray construction technology can enhance the high-temperature resistance of UHPC, it is insufficient to provide complete protection against high-temperature spalling for sprayed ultra-high-performance concrete (SUHPC). Incorporating polypropylene fiber (PP fiber) into SUHPC is an effective method to reduce the high-temperature spalling of SUHPC. To study the impact of polypropylene fiber on the performance of SUHPC, mechanical properties and high-temperature resistance tests were conducted on SUHPC. This study demonstrates that varying PP fiber content (the dosage range is 1 ‰ to 8 ‰) influences the mechanical properties, high-temperature resistance, and spalling resistance of SUHPC. To ensure optimal mechanical and high-temperature resistance properties, selecting the appropriate polypropylene fiber content is crucial. Specifically, a 1 ‰ PP fiber content increased compressive strength by approximately 10 %, whereas an 8 ‰ content caused an over 40 % reduction in bending strength. Crucially, after high-temperature exposure, all SUHPC doped with PP fiber exhibited exceptional residual strength retention rates, exceeding 1.1 and reaching a maximum of 1.8. Mercury intrusion porosimetry (MIP) analysis revealed that although total porosity increased with temperature, the proportion of small pores (5–50 nm) that maintain excellent mechanical properties still maintains a large proportion. In addition, through the analysis of the spraying time of SUHPC with different PP fiber content, the higher PP fiber content (>5 ‰) will exhibit the phenomenon of spray agglomeration. Therefore, to ensure that SUHPC exhibits excellent high temperature resistance while still maintaining high mechanical properties and construction performance, it is recommended that the PP fiber content range is 1 ‰ to 5 ‰.

超高性能混凝土（UHPC）的致密结构使其在高温环境中容易剥落。虽然喷涂施工技术可以增强UHPC的耐高温性能，但对于喷涂超高性能混凝土（SUHPC）来说，喷涂施工技术还不足以对其提供完全的高温剥落保护。在SUHPC中掺入聚丙烯纤维（PP纤维）是减少SUHPC高温剥落的有效方法。为研究聚丙烯纤维对SUHPC性能的影响，对SUHPC进行了力学性能和耐高温性能试验。研究表明，不同的PP纤维含量（用量范围为1 ‰~ 8 ‰）会影响SUHPC的力学性能、耐高温性能和抗剥落性能。为了确保最佳的机械和耐高温性能，选择合适的聚丙烯纤维含量是至关重要的。具体来说，1 ‰的PP纤维含量增加抗压强度约10 %，而8 ‰的含量导致弯曲强度降低40 %以上。关键是，高温暴露后，所有掺PP纤维的SUHPC都表现出异常的残余强度保持率，超过1.1，最高达到1.8。压汞孔隙度（MIP）分析表明，虽然总孔隙度随温度升高而增加，但保持优异力学性能的小孔隙（5 ~ 50 nm）所占比例仍然很大。此外，通过对不同PP纤维含量的SUHPC喷涂时间的分析，较高的PP纤维含量（>5 ‰）会出现喷雾结块现象。因此，为确保SUHPC在保持较高力学性能和施工性能的同时，又能表现出优异的耐高温性能，建议PP纤维含量范围为1 ‰~ 5 ‰。

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引用次数: 0

LDHs encapsulated phase change material: Towards a highly reflective and thermal storage asphalt pavement for alleviating the urban heat island effect LDHs封装相变材料：面向高反射和储热沥青路面，缓解城市热岛效应

IF 8 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Construction and Building Materials

Pub Date : 2026-01-24 DOI: 10.1016/j.conbuildmat.2026.145404

Zihao Lu , Quantao Liu , Shaopeng Wu , Huan Wang , Qinhao Deng , Xing Gong

The thermal storage systems based on Phase change materials (PCMs) and the high reflectivity of pavement reflective materials (PRMs) can efficiently mitigate urban heat islands (UHI) effect. However, the low stability of PCM and the uncontrollable reflectivity of PRMs limit their practical application. Therefore, a novel shape-stabilized PCM (LA-SA LDHs) was prepared by intercalating Stearic acid - Lauric acid PCM (LA-SA PCM) into the interlayers of layered double hydroxides (LDHs). Compared to previous preparation methods for PCM/LDHs, the LA-SA intercalated LDHs not only involve ionic bonding but also exhibit a nanoconfinement effect, which imparts exceptional shape stability to the composite. Then, the LA-SA LDHs mixed into asphalt to prepare reflective and thermal storage asphalt concrete (LA-SA LDHs MAC). The performance of LA-SA LDHs were characterized by X-ray diffraction, scanning electron microscopy, Fourier-transform infrared spectroscopy, differential scanning calorimetry, and heating-cooling cycle tests. The road performance and thermodynamic performance of LA-SA LDHs MAC were evaluated by the Marshall test, rutting test, and photothermal conversion test. The results show that LA-SA LDHs have a high phase change material retention rate (95.13 %), a satisfactory melting enthalpy (177.2 J/g). LA-SA LDHs MAC reduces the average road surface temperature by 3.06 °C. This study combines the reflective performance of LDHs with the heat storage characteristics of PCM, proposing a novel approach to mitigating the UHI effect.

基于相变材料（PCMs）和路面反射材料（PRMs）的高反射率储热系统可以有效缓解城市热岛效应。然而，PCM的低稳定性和PRMs的不可控反射率限制了其实际应用。因此，将硬脂酸-月桂酸PCM （LA-SA PCM）嵌入层状双氢氧化物（LDHs）中间层制备了一种新型的形状稳定PCM （LA-SA LDHs）。与以往的PCM/LDHs制备方法相比，LA-SA嵌入LDHs不仅涉及离子键，而且具有纳米约束效应，这使复合材料具有优异的形状稳定性。然后，将LA-SA LDHs掺入沥青中，制备反光储热沥青混凝土（LA-SA LDHs MAC）。采用x射线衍射、扫描电子显微镜、傅里叶变换红外光谱、差示扫描量热法和冷热循环试验对LA-SA低密度聚合物的性能进行了表征。采用Marshall试验、车辙试验和光热转换试验对LA-SA LDHs MAC的道路性能和热力学性能进行了评价。结果表明，LA-SA LDHs具有较高的相变材料保留率（95.13 %）和令人满意的熔融焓（177.2 J/g）。LA-SA LDHs MAC可使路面平均温度降低3.06℃。本研究将ldh的反射性能与PCM的储热特性相结合，提出了一种减轻UHI效应的新方法。

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引用次数: 0

Moisture-activated set-recovery of thermo-hydro-mechanically densified hardwood dowels for high-tolerance timber connections 用于高耐受性木材连接的热-水-机械致密硬木销钉的湿活化回固

IF 8 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Construction and Building Materials

Pub Date : 2026-01-24 DOI: 10.1016/j.conbuildmat.2026.145401

Lei Han , Alexander Scharf , Mohammad Derikvand , Matthew Schwarzkopf , Bogdan Mitkovski , Dick Sandberg , Andreja Kutnar

Conventional wooden dowel connections in timber structures rely on tight press-fit installation, which requires high insertion forces and often loosens over time due to stress relaxation. This study investigates an alternative approach that exploits the moisture-activated set-recovery of thermo-hydro-mechanically (THM) densified hardwood dowels to enable slip-fit assembly followed by self-tightening in service. To this end, European beech and black poplar were densified radially and tangentially at different compression ratios. They were then evaluated for swelling kinetics, swelling pressure, bending performance, and moisture-activated expansion using in-situ X-ray CT in water at 20 °C and 100 °C. Results show that activation kinetics can be controlled by temperature. Expansion was rapid within minutes in hot water and slower but equivalent in magnitude at room temperature. Beech outperformed poplar, with radial densification at 35 % compression ratio producing a peak swelling pressure of 5.7 MPa and a modulus of rupture of 268 MPa after activation. Poplar generated higher free expansion but significantly lower pressure due to its lower stiffness. Radial densification was consistently more effective than tangential, enhancing both expansion magnitude and pressure generation. Capillary uptake triggered expansion along the dowel length (∼30 mm in 1 h) and produced an elliptical expansion profile. Importantly, mechanical strength was retained post-activation, which confirms structural suitability. These results demonstrate that THM-densified beech dowels can offer a robust self-tightening mechanism, combining low-force installation with durable pressure generation and stable mechanical performance. This provides a viable path toward adhesive-free, metal-free, high-tolerance timber connections.

木结构中的传统木榫连接依赖于紧密的压合安装，这需要很高的插入力，并且由于应力松弛而经常随着时间的推移而松动。本研究研究了一种替代方法，该方法利用热流体机械（THM）致密硬木榫的湿气激活固井回收技术，实现滑合组装，然后在使用中进行自拧紧。为此，在不同压缩比下对欧洲山毛榉和黑杨树进行径向和切向密实。然后使用原位x射线CT在20°C和100°C的水中评估它们的膨胀动力学、膨胀压力、弯曲性能和水分激活膨胀。结果表明，活化动力学可由温度控制。在热水中，几分钟内膨胀迅速，在室温下，膨胀速度较慢，但大小相当。山毛榉优于杨树，在35 %压缩比下径向致密化，激活后的峰值膨胀压力为5.7 MPa，破裂模量为268 MPa。杨木由于刚度较低，自由膨胀率较高，但压力明显较低。径向致密化始终比切向致密化更有效，增强了膨胀幅度和压力产生。毛细管吸收触发沿销钉长度（1 h ~ 30 mm）膨胀，并产生椭圆膨胀曲线。重要的是，活化后机械强度保持不变，这证实了结构的适用性。这些结果表明，thm致密山毛榉销钉可以提供强大的自紧机制，将低力安装与持久的压力产生和稳定的机械性能相结合。这为无粘合剂、无金属、高耐受性的木材连接提供了可行的途径。

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引用次数: 0

Quasi-static and dynamic crushing behavior of Kirigami folded circular tubes Kirigami折叠圆管的准静态和动态破碎行为

IF 8 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Construction and Building Materials

Pub Date : 2026-01-24 DOI: 10.1016/j.conbuildmat.2026.145328

Bin Xu , Wenjun Bai , Cheng Wang

This study proposes a kirigami-inspired Folded Circular Tube (KFC) as a novel thin-walled sacrificial energy-absorbing component for enhancing the impact resistance of load-bearing building columns. The KFC was designed to achieve high energy absorption capacity and improved impact resistance, and was evaluated against a conventional circular tube and a hierarchical configuration (HC) counterpart of identical wall thickness and mass. Quasi-static axial compression tests were conducted to investigate the collapse behavior and energy absorption characteristics, while validated finite element models were employed to quantify key crashworthiness indicators, including the specific energy absorption (SEA) and crushing force efficiency (CFE). Results indicate that the KFC exhibits superior structural stiffness and energy absorption performance, with a 7 % higher SEA and a 1.63-folds of CFE than the HC structure. Under quasi-static loading, foam filling effectively stabilized the deformation of the KFC-A configuration and enhanced the energy absorption of KFC-C by 9 %. Low-velocity impact tests further confirmed that the KFC structures achieved a significantly lower initial peak crushing force (only 26 % of that of the HC), a smoother plateau response, and minimal IPCF amplification under dynamic effects. Overall, the KFC demonstrates clear advantages over the HC design, highlighting the critical role of geometric tailoring in improving crashworthiness. These results demonstrate the potential of KFC structures as lightweight, high-performance energy-absorbing components for applications requiring impact-resistant building elements.

本研究提出了一种受kirigami启发的折叠圆管（KFC）作为一种新型薄壁牺牲吸能构件，用于增强承重建筑柱的抗冲击能力。肯德基的设计旨在实现高能量吸收能力和提高抗冲击性，并与传统的圆形管和相同壁厚和质量的分层结构（HC）相比较进行了评估。通过准静态轴压试验研究了结构的崩溃行为和能量吸收特性，并采用验证的有限元模型量化了结构的关键耐撞性指标，包括比能量吸收（SEA）和破碎力效率（CFE）。结果表明，KFC结构刚度和吸能性能优于HC结构，SEA比HC结构高7 %，CFE是HC结构的1.63倍。在准静态载荷作用下，泡沫填充有效地稳定了KFC-A结构的变形，使KFC-C的吸能提高了9 %。低速冲击试验进一步证实，KFC结构的初始峰值破碎力明显较低（仅为HC的26% %），平台响应更平滑，在动力作用下IPCF放大最小。总的来说，肯德基展示了明显优于HC设计的优势，突出了几何剪裁在提高耐撞性方面的关键作用。这些结果证明了肯德基结构作为轻质、高性能吸能组件的潜力，适用于需要抗冲击建筑元件的应用。

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引用次数: 0

Properties and retarding mechanism of alkali-activated slag cement modified by zinc acetate 醋酸锌改性碱活性矿渣水泥的性能及缓凝机理

IF 8 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Construction and Building Materials

Pub Date : 2026-01-24 DOI: 10.1016/j.conbuildmat.2026.145391

Yue Li, Haoyu Wang, Hui Lin, Jiale Shen, Tianze Song, KaiKai Jin

Alkali-activated slag cement is a green cementing material with advantages such as high strength and good durability, but it hardens rapidly at room temperature, which limits its application and promotion to some extent. This article mainly studies the effect of zinc acetate dosage on the setting time, workability, and mechanical properties of alkali-activated slag cement (AAS), and explores the regulatory mechanism of zinc acetate on the setting and hardening of alkali slag cement by combining testing methods such as heat measurement, ICP-OES, FTIR, and TG-DTG. The results show that zinc acetate can effectively extend the setting time of AAS, and when the dosage is within 1.5 %, it has a minor impact on the workability and mechanical properties of AAS; however, excessive zinc acetate will significantly reduce the fluidity and compressive strength of AAS. Microscopic results indicate that the addition of zinc acetate generates CaZn₂(OH)₆ products in the solution and delays the setting time of AAS by inhibiting the nucleation process of the cementing products. Excessive zinc acetate will notably decrease the amount of C-A-S-H gel products in the matrix, leading to a significant decline in the mechanical properties of AAS.

碱活化矿渣水泥是一种绿色胶结材料，具有强度高、耐久性好等优点，但室温下硬化快，在一定程度上限制了其应用和推广。本文主要研究醋酸锌用量对碱活性矿渣水泥（AAS）凝结时间、和易性和力学性能的影响，并结合热测量、ICP-OES、FTIR、TG-DTG等测试方法，探讨醋酸锌对碱活性矿渣水泥凝结硬化的调控机理。结果表明：醋酸锌能有效延长原子吸收剂的凝固时间，当用量在1.5 %以内时，对原子吸收剂的和易性和力学性能影响不大；但过量的醋酸锌会显著降低AAS的流动性和抗压强度。微观结果表明，醋酸锌的加入在溶液中生成CaZn2(OH)6产物，通过抑制胶结产物的成核过程，延缓了AAS的凝固时间。过量的醋酸锌会显著减少基体中C-A-S-H凝胶产物的数量，导致AAS的力学性能明显下降。

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引用次数: 0

Dynamic response of two Scott Blair fractional-type elements in series: Interpretation of dynamic shear rheometry data and the effect of bitumen aging and rejuvenation on model parameters 两个Scott Blair分数型单元的动态响应：动态剪切流变学数据的解释以及沥青老化和再生对模型参数的影响

IF 8 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Construction and Building Materials

Pub Date : 2026-01-24 DOI: 10.1016/j.conbuildmat.2026.145180

Christian Pichler, Lukas Perfler, Roman Lackner

In this paper, we revisited viscoelastic modeling of bitumen by employing the Scott Blair element, with the latter frequently termed as nonlinear, power-law, or fractional damper, respectively or as springpot. Straightforwardly, two Scott Blair elements in series suffice as an effective tool for the assessment of the stiffening state of bitumen within its life cycle, affected by aging and rejuvenation. Furthermore, we suggest a protocol on how to effectively handle data from dynamic shear rheometry (DSR), frequency and temperature sweep data, allowing to objectively backcalculate model parameters, i.e. power-law compliance parameters and power-law exponents, for the two Scott Blair elements. One (or more) of these model parameters may then be employed to assess the base state, the aging state and rejuvenation state of bitumen samples. Hence, the proposed data handling and interpretation protocol allows for the explicit assessment of the aging state on the basis of model parameters over the entire frequency and temperature spectrum investigated. This is an improvement as regards the regular assessment of DSR data, where storage, loss, and/or norm of the complex modulus, respectively, are either depicted for a certain frequency as a function of temperature or vice versa, i.e. for a certain temperature as a function of frequency used in the DSR test. Hence, the proposed protocol allows for a more holistic assessment of the state of bitumen and makes the straightforward comparison between different bitumen varieties/grades and between variously aged/rejuvenated states of one bitumen variety more graphic and tangible.

在本文中，我们通过使用Scott Blair单元重新审视了沥青的粘弹性建模，后者通常被称为非线性，幂律或分数阻尼器，分别或作为弹簧。简单地说，两个Scott Blair元素序列足以作为评估沥青在其生命周期内受老化和返老还老影响的硬化状态的有效工具。此外，我们提出了一个如何有效处理动态剪切流变学（DSR）数据、频率和温度扫描数据的协议，允许客观地反算两个Scott Blair元素的模型参数，即幂律顺应性参数和幂律指数。这些模型参数中的一个（或多个）可以用来评估沥青样品的基本状态、老化状态和返老还老状态。因此，提出的数据处理和解释协议允许在整个频率和温度谱研究的基础上，基于模型参数对老化状态进行明确的评估。对于DSR数据的常规评估来说，这是一个改进，其中复模量的存储、损失和/或范数分别被描述为温度的函数或相反，即在DSR测试中使用的频率的函数。因此，拟议的协议允许对沥青的状态进行更全面的评估，并使不同沥青品种/等级之间以及一种沥青品种的不同老化/再生状态之间的直接比较更加直观和有形。

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引用次数: 0

Effect of mineral admixtures on the tobermoritization in monticellite 矿物掺合物对蒙脱石中钛矿化的影响

IF 8 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Construction and Building Materials

Pub Date : 2026-01-24 DOI: 10.1016/j.conbuildmat.2026.145392

Qisheng Wu, Nan Sun, Zheyu Zhu, Huajun Zhu

The formation of tobermorite serves as a critical link between inert solid wastes and high-performance materials. This study systematically investigates the effects of four mineral admixtures-kaolin, fly ash, ground granulated blast-furnace slag, and silica fume-on the tobermoritization process of monticellite, as well as the relationship between the underlying mechanisms and the resulting material properties. The results indicate that the mixture with 20 wt% silica fume achieved the highest compressive strength (35.9 MPa) and the maximum dry density (1888.75 kg/m³), which can be attributed to the highly reactive SiO₂ directly facilitating the formation of fibrous tobermorite. Kaolin, at a 20 wt% dosage, enhanced the strength by 5.38 times through aluminum doping, leading to the formation of a highly cross-linked C-A-S-H gel. The strengthening effect of slag was found to be inferior to that of silica fume and fly ash. Mineral admixtures promote tobermorite formation by regulating the Ca/Si ratio, supplying reactive sources of silicon and aluminum, and optimizing the microstructure. This research provides a theoretical basis for controlling the phase transformation of monticellite.

托贝莫来石的形成是惰性固体废物与高性能材料之间的关键环节。本研究系统地考察了高岭土、粉煤灰、磨粒高炉渣和硅灰四种矿物外加剂对蒙脱石氧化石化过程的影响，以及其作用机理与材料性能之间的关系。结果表明：掺量为 wt%的硅灰混合物的抗压强度最高（35.9 MPa），干密度最高（1888.75 kg/m³），这是由于sio2的高活性直接促进了纤维状托博莫里石的形成。高岭土在掺量为20 wt%时，通过铝掺杂，强度提高了5.38倍，形成了高度交联的C-A-S-H凝胶。结果表明，矿渣的强化效果不如硅灰和粉煤灰。矿物掺合料通过调节Ca/Si比、提供硅和铝的活性源以及优化微观结构来促进托贝莫来石的形成。该研究为控制蒙蒂卫星相变提供了理论依据。

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引用次数: 0

Effects of pozzolanic reactivity and mixture compactness on the mechanical performance of low-carbon concretes incorporating high levels of glass powder, rock wool powder, or rice husk ash 火山灰反应性和混合物密实度对含高水平玻璃粉、岩棉粉或稻壳灰的低碳混凝土机械性能的影响

IF 8 1区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Construction and Building Materials

Pub Date : 2026-01-24 DOI: 10.1016/j.conbuildmat.2026.145365

Eliana Soldado , Hugo Costa , Ricardo do Carmo , Eduardo Júlio

Reducing Portland cement consumption through the incorporation of alternative supplementary cementitious materials (SCMs) is central to developing low-carbon concrete (LCC) for a more sustainable construction industry. This study evaluates LCC mixtures incorporating alternative SCMs – glass powder, rock wool residue powder, or high-carbon rice husk ash – combined with a complementary content of limestone filler. To compare and isolate the influence of mixture compactness from SCM pozzolanic reactivity, analogous mixtures containing fly ash, limestone filler, or Portland cement at equivalent substitution levels were also produced, together with a conventional concrete designed according to standard parameters. Unlike most existing studies constrained by binder specifications and current standard limitations on substitution levels, this work investigates high cement replacement ratios of 17 %, 35 %, and 50 % within a fixed total powder content of 350 kg/m³ . This experimental framework enables the decoupling of SCM reactivity from mixture compactness, providing a clearer understanding of their individual effects on mechanical performance. Comprehensive testing in both fresh (slump, air content, density, and setting times) and hardened states (pozzolanic activity index, compressive, splitting tensile and flexural strengths, and Young’s modulus) shows that substantial reductions in cement content can be achieved without compromising concrete behaviour. The mixtures with 35 % cement replacement consistently achieved the best results. The findings demonstrate the feasibility of performance-based mix design for LCC with high contents of alternative SCMs and offer practical guidance for optimising mixture design and promoting the sustainable use of these materials in structural concrete beyond current standard limits.

通过加入替代补充胶凝材料（scm）来减少波特兰水泥的消耗，是开发低碳混凝土（LCC）以实现更可持续建筑行业的核心。本研究评估了LCC混合物中可选择的SCMs——玻璃粉、岩棉渣粉或高碳稻壳灰——与石灰石填料的补充含量相结合。为了比较和分离SCM火山灰反应性对混合物密实度的影响，还生产了含有同等取代水平的粉煤灰、石灰石填料或波特兰水泥的类似混合物，以及根据标准参数设计的常规混凝土。与大多数受粘合剂规格和现行替代水平标准限制的现有研究不同，本研究在固定的总粉含量为350 kg/m³ 的情况下，研究了高水泥替代率，分别为17 %、35 %和50 %。该实验框架使SCM反应性与混合物密实度解耦，从而更清楚地了解它们对机械性能的个别影响。对新鲜状态（坍落度、空气含量、密度和凝结时间）和硬化状态（火山灰活性指数、压缩、劈裂拉伸和弯曲强度以及杨氏模量）的综合测试表明，在不影响混凝土性能的情况下，可以大幅降低水泥含量。水泥替代量为35% %的混合物始终取得最佳效果。研究结果表明，对于含有高含量可选scm的低密度混凝土，基于性能的配合比设计是可行的，并为优化配合比设计和促进这些材料在结构混凝土中的可持续使用提供了实际指导，超出了目前的标准限制。

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