Cement and Concrete Research最新文献_第3页

Development of CO2-induced SCMs for calcium sulfoaluminate cement: Towards enhancing hydration, compressive strength and later stage-ettringite stability 二氧化碳诱导的硫铝酸钙水泥SCMs的发展：朝着提高水化、抗压强度和后期钙矾石稳定性的方向发展

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

Cement and Concrete Research

Pub Date : 2025-12-30 DOI: 10.1016/j.cemconres.2025.108121

Kai Cui , Danyang Zhao , Yingliang Zhao , Yong Zheng , Weiwei Wu , Qinglong Qin , Fenghua Nie , Jun Chang , Peiliang Shen , Chi Sun Poon

Calcium sulfoaluminate cement (CSA) often exhibits limited long-term strength due to the lack of suitable supplementary cementitious materials (SCMs) that can effectively promote secondary hydration. This study introduces a novel approach for preparing CO₂ induced SCMs (CSCMs) derived from CSA, aiming to overcome this limitation and enhance both hydration kinetics and mechanical performance. CSCMs, produced by CO₂ induced CSA for three hours, consist of polycrystalline calcium carbonate phases, specifically, aragonite (7.6 %), vaterite (2.1 %) and calcite (22.4 %), alongside amorphous AlSi gel. When incorporated into CSA at a dosage of 10 wt%, these CSCMs significantly accelerated hydration, resulting in increased formation of AFt and AH₃, which boosted early compressive strength by 22.7 % in one day and 14.4 % at three days compared to control samples. Beyond early strength gains, the presence of CSCMs facilitated further reactions among calcium carbonate, AlSi gel, and C₄A₃Š, leading to the generation of Mc and Hc phases. These products stabilized AFt and contributed to improving compressive strength over extended curing periods. After 180 days, samples containing CSCMs exhibited strength increases of 26.1 % (5 % CSCMs), 31.8 % (10 % CSCMs), and 27.2 % (20 % CSCMs), while the control sample experienced a 5.9 % strength reduction and 8.2 % AFt decomposition. The enhanced performance is attributed to the high reactivity and nucleation effects of the calcium carbonate and AlSi gel components. This study developed low-cost CSCMs for dedicated CSA, while resolving the conflict between CSA strength development and carbon emission reduction.

由于缺乏合适的补充胶凝材料（SCMs）来有效地促进二次水化，硫铝酸钙水泥（CSA）的长期强度往往有限。本研究介绍了一种由CSA衍生的CO2诱导SCMs （CSCMs）的新方法，旨在克服这一限制，提高水化动力学和力学性能。CSCMs由CO2诱导CSA制备3小时，由多晶碳酸钙相组成，特别是文石（7.6%），水晶石（2.1%）和方解石（22.4%），以及无定形AlSi凝胶。当以10 wt%的剂量加入到CSA中时，这些CSCMs显著加速了水化，导致AFt和AH3的形成增加，与对照样品相比，在一天内提高了22.7%的早期抗压强度，在三天内提高了14.4%。除了早期强度的增加，CSCMs的存在促进了碳酸钙、AlSi凝胶和C4A3Š之间的进一步反应，导致Mc和Hc相的生成。这些产品稳定了AFt，并有助于在延长的固化期间提高抗压强度。180天后，含有CSCMs的样品强度增加了26.1% (5% CSCMs), 31.8% （10% CSCMs）和27.2% (20% CSCMs)，而对照样品强度降低了5.9%，AFt分解了8.2%。这种增强的性能归因于碳酸钙和AlSi凝胶组分的高反应活性和成核效应。本研究在解决CSA强度发展与碳减排矛盾的同时，开发了用于专用CSA的低成本CSCMs。

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引用次数: 0

Optimizing Mg/PO4 molar ratio for ultra-high-performance steel fiber-reinforced magnesium potassium phosphate cement-based composite 超高性能钢纤维增强磷酸镁钾水泥基复合材料Mg/PO4摩尔比优化

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

Cement and Concrete Research

Pub Date : 2025-12-24 DOI: 10.1016/j.cemconres.2025.108126

Yizhou Zhao , Barbara Lothenbach , Zhangli Hu , Biwan Xu

The magnesium-to-KH₂PO₄ (Mg/PO₄) molar ratio is crucial for magnesium potassium phosphate (MKP) cement-based composites. To develop Ultra-High-Performance Cement-based Composite (UHPCC) using MKP cement, the effect of Mg/PO₄ molar ratios (4–8) on the properties and microstructure of steel fiber-reinforced MKP cement-based composites was investigated. Increasing the Mg/PO₄ ratio accelerated the hydration kinetics, without compromising flowability. The lowest molar ratio (Mg/PO₄ = 4) resulted in significant shrinkage, whereas ratios ≥6 induced slight expansion. The optimal molar ratio was determined to be Mg/PO₄ = 7, which yielded a composite meeting UHPCC requirements, with 28-day compressive, flexural, and tensile strengths of ∼132 MPa, ∼ 44 MPa, and ∼ 14 MPa, respectively. The optimum properties achieved at this ratio can be attributed to the highest fiber-matrix bonding stress and a denser microstructure with a more rational composition, leading to higher local elastic modulus, increased hardness, and improved crack resistance.

镁与kh2po4 （Mg/PO₄）的摩尔比对磷酸钾镁（MKP）水泥基复合材料至关重要。为了研制MKP水泥的超高性能水泥基复合材料（UHPCC），研究了Mg/PO₄摩尔比（4-8）对钢纤维增强MKP水泥基复合材料性能和微观结构的影响。提高硫酸镁比可加快水化动力学，但不影响流动性。最低的摩尔比（Mg/PO₄= 4）会导致明显的收缩，而摩尔比≥6会引起轻微的膨胀。确定最佳摩尔比为Mg/PO4 = 7，得到符合UHPCC要求的复合材料，其28天抗压、抗折和抗拉强度分别为~ 132 MPa、~ 44 MPa和~ 14 MPa。在此比率下获得的最佳性能可归因于最高的纤维-基体结合应力和更致密的微观结构以及更合理的成分，从而导致更高的局部弹性模量，更高的硬度和更好的抗裂性。

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引用次数: 0

1H NMR relaxation analysis of cement-based materials: The spin-lock T1ρ experiment and the partitioning of water in C-S-H inter-layer spaces 水泥基材料的1H NMR弛豫分析：自旋锁T1ρ实验和C-S-H层间空间中水的分配

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

Cement and Concrete Research

Pub Date : 2025-12-23 DOI: 10.1016/j.cemconres.2025.108125

Peter J. McDonald , David A. Faux , Longfei Ma , Hong Wong

In recent years, ¹H NMR relaxometry has become a mainstream methodology for study of the nano-porosity of cement-based materials. For the most part, measurements have been carried out using variants of the classic CPMG

T_{2}

and solid-echo NMR pulse sequences and, to a lesser extent, the inversion recovery

T_{1}

sequence.

Notwithstanding considerable successes, these methods all have one or another disadvantage, quite often associated with reliable differentiation of the so-called inter-layer and quasi-crystalline water fractions. In this paper, we introduce the application of the

T_{1 ρ}

spin-lock experiment as a convenient alternative methodology. Early results are presented. Measuring

T_{1 ρ}

overcomes some of the earlier difficulties, potentially has some wider advantages but also has raised some interesting questions of interpretation associated with the partitioning of water between C-S-H interlayer spaces and quasi-crystalline phases.

近年来，1H核磁共振弛豫法已成为水泥基材料纳米孔隙度研究的主流方法。在大多数情况下，使用经典CPMG T2T2和固体回波核磁共振脉冲序列的变体进行测量，并且在较小程度上使用反演恢复T1T1序列。尽管取得了相当大的成功，但这些方法都有这样或那样的缺点，往往与所谓的层间和准结晶水馏分的可靠区分有关。本文介绍了t1ρ ρ自旋锁实验作为一种方便的替代方法的应用。提出了初步结果。测量t1ρ ρ克服了早期的一些困难，潜在地具有一些更广泛的优势，但也提出了一些有趣的解释问题，这些问题与C-S-H层间空间和准晶相之间的水分配有关。

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引用次数: 0

Deciphering the initial hydration reaction of tricalcium aluminate based on Ab initio-accurate machine learning force field 基于从头算精确机器学习力场的铝酸三钙初始水化反应解译

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

Cement and Concrete Research

Pub Date : 2025-12-22 DOI: 10.1016/j.cemconres.2025.108124

Weihuan Li , Chenchen Xiong , Yang Zhou , Yangzezhi Zheng , Jiarui Xing , Yanji Jin , Yulin Wang

Mineral dissolution is a critical phenomenon in various fields, particularly in the early hydration of Portland cement. Despite its importance, atomic-scale mechanisms remain elusive due to limitations in experimental and computational methods. Using an efficient sampling strategy that integrates metadynamics and targeted molecular dynamics, we developed a deep learning interatomic potential with quantum-level accuracy and scalable computational efficiency to reveal the dissolution mechanisms of tricalcium aluminate (C₃A). The results uncover distinct dissociation pathways of calcium and aluminate ions. Specifically, Ca ions follow a ligand-exchange mechanism, preferentially transitioning to an unsaturated coordination state before bonding with water molecules. Conversely, Al ions first coordinate with water molecules to reach a supersaturated coordination state, which promotes the opening of six-membered rings and the cleavage of Al ions. This work elucidates the thermodynamics of C₃A dissolution, deepening the understanding of mineral-water interfacial reactions, and provides an efficient, accurate approach for probing complex reaction pathways.

矿物溶解是各个领域的关键现象，特别是在硅酸盐水泥的早期水化过程中。尽管它很重要，但由于实验和计算方法的限制，原子尺度的机制仍然难以捉摸。利用整合元动力学和靶向分子动力学的高效采样策略，我们开发了具有量子级精度和可扩展计算效率的深度学习原子间势，以揭示铝酸三钙（C3A）的溶解机制。结果揭示了不同的解离途径的钙和铝酸盐离子。具体来说，钙离子遵循配体交换机制，在与水分子结合之前优先过渡到不饱和配位态。相反，Al离子首先与水分子配位，达到过饱和配位状态，促进六元环的打开和Al离子的裂解。这项工作阐明了C3A溶解的热力学，加深了对矿泉水界面反应的理解，并为探测复杂的反应途径提供了一种高效、准确的方法。

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引用次数: 0

Quantitative dependence of dynamic drying shrinkage of white cement pastes on pore-scale water removal kinetics 白水泥浆体动态干燥收缩对孔隙尺度脱水动力学的定量依赖

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

Cement and Concrete Research

Pub Date : 2025-12-22 DOI: 10.1016/j.cemconres.2025.108117

Huaming Liang , Hanlin Zou , Huan Wang , Zhendi Wang , Chunsheng Zhou

To quantify the correlation between dynamic drying shrinkage and pore-scale water removal kinetics, the pore-scale water allocation and dynamic shrinkage of white cement pastes upon drying at 75%, 43%, and 11% RHs were monitored and analyzed. Experimental results show a bilinear dependence of dynamic shrinkage on the removals of interlayer and gel water within CSH gel irrespective of RHs. CSH gel behaves like flexible hydrous sponges skewered by a stiff skeleton. Although CSH sponges lose water and contract remarkably upon drying, the spatial constraint of skeleton limits the deformation of pastes. Consequently, only 0.72% to 4.23% of interlayer and gel water losses are translated into measurable shrinkage. The removal of gel water contributes to shrinkage more than that of interlayer water due to the larger size of gel pores, though both their contributions decrease with declining RH and become similar. Mitigating shrinkage necessitates reducing CSH contraction and enhancing skeleton stiffness.

为了量化动态干燥收缩与孔隙尺度脱水动力学之间的相关性，对75%、43%和11% RHs条件下白色水泥浆体干燥时的孔隙尺度水分配和动态收缩进行了监测和分析。实验结果表明，与RHs无关，动态收缩与CSH凝胶内层间水和凝胶水的去除率呈双线性关系。CSH凝胶的行为就像由坚硬骨架串在一起的柔性含水海绵。虽然CSH海绵在干燥时失水收缩明显，但骨架的空间约束限制了膏体的变形。因此，只有0.72%至4.23%的层间和凝胶水损失转化为可测量的收缩。凝胶水的去除比层间水的去除对收缩的贡献更大，因为凝胶孔的尺寸更大，但两者的贡献都随着相对湿度的降低而减小，并趋于相似。减少收缩需要减少CSH收缩和提高骨架刚度。

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引用次数: 0

Thermodynamic simulation-assisted design of the electrolytic manganese residue-slag-Ca(OH)2 cementitious system: Reaction and Mn immobilization 电解锰渣-炉渣- ca (OH)2胶凝体系的热力学模拟辅助设计：反应与Mn固定化

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

Cement and Concrete Research

Pub Date : 2025-12-22 DOI: 10.1016/j.cemconres.2025.108119

Lang Pang , Jianwei Sun , John L. Provis , Barbara Lothenbach , Bin Ma , Dengquan Wang

The disposal of electrolytic manganese residue (EMR) is a critical challenge. This study introduces an EMR-blast furnace slag-Ca(OH)₂ cementitious system (EG^CH), utilizing the gypsum in EMR to activate the slag to form a product resembling a supersulfated cement. With up to 40 % EMR incorporation, it achieves compressive strengths of 16.8 MPa at 3 d and 33.2 MPa at 28 days. The primary reaction products are AFt, C-A-S-H and hydrotalcite. A thermodynamic simulation-assisted iterative calculation was developed and validated by pore solution analysis, to accurately quantify phase evolution. EMR content significantly influences the reaction and results in distinct exothermic profiles. The optimal 40 % EMR content results in the densest microstructure due to the balanced formation of AFt and C-A-S-H. Mn is immobilized in EG^CH with two barriers to its leaching and cannot leach out until the pH drops below 7. This binder offers a practical solution for the utilization of EMR.

电解锰渣（EMR）的处理是一个严峻的挑战。本研究介绍了EMR-高炉矿渣- ca (OH)2胶凝体系（EGCH），利用EMR中的石膏活化矿渣，形成类似超硫酸盐水泥的产品。EMR掺入量高达40%，3d抗压强度为16.8 MPa， 28天抗压强度为33.2 MPa。主要反应产物为AFt、C-A-S-H和水滑石。建立了一种热力学模拟辅助迭代计算方法，并通过孔隙溶液分析验证了该方法的准确性。EMR含量显著影响反应并导致不同的放热曲线。最佳EMR含量为40%时，由于AFt和C-A-S-H的形成平衡，导致微观结构最致密。Mn被固定在EGCH中，有两种阻碍其浸出的障碍，直到pH降至7以下才会浸出。这种粘合剂为电子病历的利用提供了一种实用的解决方案。

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引用次数: 0

The role of carbonate anions and early-formed phases on the efficiency of PCE in alkali-activated slag 碱渣中碳酸盐阴离子和早期形成相对PCE效率的影响

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

Cement and Concrete Research

Pub Date : 2025-12-20 DOI: 10.1016/j.cemconres.2025.108122

Yuliang Wang, Shengnan Sha, Hailong Ye

The mechanism responsible for the reduced dispersing efficiency of polycarboxylate ether (PCE) superplasticizers in carbonate-activated slag system (AAS) remains controversial and ambiguous, particularly regarding the roles of carbonate anions and early-formed phases. This study systematically evaluated the fluidity and adsorption behavior of PCE in K₂CO₃-activated slag with varying alkali modulus and in CaO-K₂CO₃-activated slag. Results show that in K₂CO₃-activated slag systems, the inefficiency of PCE at low dosages (≤ 1 mg/g binder) is primarily due to its preferential adsorption onto early-formed calcium carbonate phases. At higher dosages (> 1 mg/g), both competitive adsorption by CO₃²⁻ ions and conformational collapse of PCE macromolecules dominate its reduced dispersing performance. In CaO–K₂CO₃-activated systems, early-formed calcium carbonate phases still consume part of the PCE at low dosages (≤ 4 mg/g). However, CaO reduces CO₃²⁻ ion concentration, weakening competitive adsorption and improving PCE dispersing efficiency compared to K₂CO₃-activated systems.

聚羧酸酯醚（PCE）高效减水剂在碳酸盐-活性渣体系（AAS）中分散效率降低的机理仍然存在争议和不明确，特别是关于碳酸盐阴离子和早期形成相的作用。研究系统地评价了PCE在不同碱模量的K₂CO₃活性渣和CaO-K₂CO₃活性渣中的流动性和吸附行为。结果表明，在K₂CO₃活性渣体系中，低剂量（≤1 mg/g粘结剂）PCE的低效率主要是由于其优先吸附在早期形成的碳酸钙相上。在较高剂量（1 mg/g）下，CO₃2−离子的竞争性吸附和PCE大分子的构象崩溃是其分散性能降低的主要原因。在CaO-K₂CO₃活化的系统中，早期形成的碳酸钙相仍然以低剂量（≤4mg /g）消耗部分PCE。然而，与K₂CO₃活化体系相比，CaO降低了CO₃2−离子浓度，削弱了竞争吸附，提高了PCE的分散效率。

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引用次数: 0

Impedance and electrical conductivity of C-S-H C-S-H的阻抗和电导率

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

Cement and Concrete Research

Pub Date : 2025-12-20 DOI: 10.1016/j.cemconres.2025.108123

Tulio Honorio , Walter Batista Bonfim , Oswaldo Cascudo

The impedance and complex electrical conductivity of C-S-H have not been directly measured, even though electromagnetic measurements are a key non-destructive technique for probing cement systems. Here, we evaluate the frequency-dependent electrical conductivity of C-S-H using molecular dynamics simulations for the first time. The effect of nanopore size is assessed for pores spanning the interlayer to the gel range, showing that interlayer conductivity is governed by subdiffusive ion dynamics while Fickean dynamics drives gel pores behavior. Ionic self-correlations dominate the conductivity, while water–ion and solid–ion contributions are smaller but non-negligible. By combining molecular dynamics with mean-field homogenization, we obtain gel-scale estimates consistent with available data (i.e., with ratio between gel conductivity and pore solution conductivity on the order of 1/100). As with other transport properties, accounting for anisotropy and associated dimensionality loss is critical for understanding electrical conductivity bottom-up. Our results provide direct evaluation of the frequency-dependent conductivity of C-S-H, offering valuable input for multiscale modeling and for interpreting electromagnetic measurements of cementitious materials.

尽管电磁测量是探测水泥体系的关键非破坏性技术，但C-S-H的阻抗和复杂电导率尚未直接测量。在这里，我们首次使用分子动力学模拟来评估C-S-H的频率依赖性电导率。纳米孔大小对层间至凝胶范围孔隙的影响进行了评估，表明层间电导率受亚扩散离子动力学控制，而Fickean动力学驱动凝胶孔隙行为。离子自相关性主导电导率，而水离子和固体离子的贡献较小，但不可忽略。通过将分子动力学与平均场均质化相结合，我们获得了与现有数据一致的凝胶尺度估计（即凝胶电导率与孔隙溶液电导率之比约为1/100）。与其他输运性质一样，考虑各向异性和相关的维度损失对于自下而上地理解电导率至关重要。我们的研究结果提供了C-S-H的频率相关电导率的直接评估，为多尺度建模和解释胶凝材料的电磁测量提供了有价值的输入。

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引用次数: 0

Sodium aluminate activated BOF steel slag: Impact of Al(OH)4− on reaction mechanism 铝酸钠活化转炉钢渣：Al(OH)4−对反应机理的影响

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

Cement and Concrete Research

Pub Date : 2025-12-19 DOI: 10.1016/j.cemconres.2025.108116

Mengyu Zhu , Yuxuan Chen , S.R. van der Laan , Tao Liu , Qingliang Yu

The limited hydraulic reactivity of Basic Oxygen Furnace (BOF) slag, caused by its low-aluminum and high-iron composition, restricts its high-value applications. This study employs sodium aluminate (NaAlO₂, NA) as an activator, with a focus on the mechanistic role of Al(OH)₄⁻ in modulating the hydration pathways of belite in BOF slag. Systematic investigations of phase evolution, microstructural development, pore solution chemistry, and mechanical properties reveal that NA significantly enhances the early reactivity of belite and brownmillerite and promotes the formation of Si(Fe)-rich hydrogarnet and C(N)-A-S-H gels, enabling synergistic hydration between belite and brownmillerite at early ages. The NA-activated pastes develop a denser microstructure, exhibiting quadrupled early strength compared to the non-activated system. Crucially, the system demonstrates superior environmental performance, with heavy metal leaching concentrations consistently below regulatory thresholds. These findings elucidate the activation mechanisms of NA and propose a viable strategy for advanced BOF slag utilization.

碱性氧炉（BOF）炉渣由于其低铝高铁的成分，导致其水力反应性有限，制约了其高价值应用。本研究采用铝酸钠（NaAlO2， NA）作为活化剂，重点研究了Al(OH)4−在转炉炉渣中调节白石水化途径的机理。系统的相演化、微观结构发育、孔隙溶液化学和力学性能研究表明，NA显著增强了白橄榄石和褐粒石的早期反应活性，促进了富Si（Fe）水榴石和C(N) a - s - h凝胶的形成，使白橄榄石和褐粒石在早期发生协同水化作用。与未激活的体系相比，na激活的膏体具有更致密的微观结构，表现出四倍的早期强度。至关重要的是，该系统表现出优越的环保性能，重金属浸出浓度始终低于监管阈值。这些发现阐明了NA的活化机理，并为转炉炉渣的高级利用提出了可行的策略。

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引用次数: 0

Synergistic sulfate-alkaline activation of one-part volcanic pumice–cement binders: Mechanisms and microstructural evolution 单组分火山浮石-水泥粘结剂硫酸盐-碱协同活化：机理与微观结构演化

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

Cement and Concrete Research

Pub Date : 2025-12-18 DOI: 10.1016/j.cemconres.2025.108103

Jesus López-Salas, J. Ivan Escalante-García

The synergistic activation of a novel one-part volcanic pumice-PC hybrid binder with a Na₂SO₄-Al₂(SO₄)₃-Ca(OH)₂ (NŜ-AŜ-CH) ternary system was elucidated using a suite of advanced characterization techniques. The reaction proceeds via two distinct pathways: a rapid sulfatic pathway, where Al₂(SO₄)₃ promotes ettringite (AFt) formation for early strength, and a primary alkaline pathway, where the Na₂SO₄-Ca(OH)₂ synergy generates in-situ NaOH, driving VP dissolution and C-(N)-A-S-H formation. This resulted in a nearly threefold increase in 1-day strength, with optimized binders reaching over 70 MPa at 90 days. Long-term analysis reveals the “dual role” of AS, as its persistent AFt provides microstructural reinforcement. This leads to a “composite strength mechanism,” a key finding where high strength is achieved even in systems with a less polymerized silicate network (low Mean Chain Length). The NS-CH synergy, in contrast, is the primary driver for high polymerization, informing a new model for designing sustainable binders.

采用一系列先进的表征技术，研究了一种新型的单组分火山浮石- pc复合粘结剂与Na₂SO₄-Al₂（SO₄）₃-Ca（OH）₂（NŜ-AŜ-CH）三元体系的协同活化作用。反应通过两种不同的途径进行：快速硫酸途径，其中Al₂（SO₄）₃促进钙矾石（AFt）的形成以获得早期强度；初级碱性途径，其中Na₂SO₄- ca (OH) 2协同作用产生原位NaOH，驱动VP溶解和C-(N) a -s - h的形成。这使得1天的强度增加了近3倍，优化后的粘合剂在90天的强度超过70 MPa。长期分析揭示了AS的“双重作用”，因为其持久的AFt提供了微观结构的强化。这导致了“复合强度机制”，这是一个关键的发现，即使在具有较少聚合硅酸盐网络（低平均链长）的系统中也能实现高强度。相比之下，NS-CH协同作用是高聚合的主要驱动因素，为设计可持续粘合剂提供了新的模型。

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引用次数: 0