Construction and Building Materials最新文献_第6页

Enhancing chemical binding of internal chlorides in ultra-high performance seawater and sea sand concrete through the synergistic effect of metakaolin and alkali-rich white mud 偏高岭土与富碱白泥协同作用增强超高性能海水和海砂混凝土中内部氯化物的化学结合

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

Construction and Building Materials

Pub Date : 2026-04-11 Epub Date: 2026-03-09 DOI: 10.1016/j.conbuildmat.2026.145855

Bohan Yang , Xiaowei Gu , Zhijun Li , Zhihang Hu , Jianping Liu , Dong Han , Qing Wang

Ultra-high performance seawater and sea sand concrete (UHPSSC) is a promising material for marine engineering applications; however, reinforcement corrosion induced by internal chlorides remains a critical challenge. This study aims to address this issue by exploring the synergistic use of metakaolin (MK) and alkali-rich white mud (WM) as supplementary cementitious materials to regulate chloride binding and mitigate corrosion risk in UHPSSC. The study investigates replacing silica fume with MK and incorporating 10 wt.% and 20 wt.% WM into UHPSSC. The mechanical properties, hydration behavior, microstructure, and chloride binding capacity are analyzed. Complete replacement of silica fume with MK reduced compressive strength from 131.5 MPa to 123.6 MPa at 28 days, while 10 wt.% WM (WM10) counteracted this reduction, increasing strength by 3%. However, 20 wt.% WM caused significant performance deterioration. Microstructural analysis revealed that MK alone deteriorates the pore structure, whereas WM10 enhances pozzolanic reactions and reduces porosity. MK significantly increases chloride immobilization, and WM further strengthens chemical chloride binding, with WM10 showing nearly twice the amount of chemically bound chlorides at 60 days compared to conventional UHPSSC. WM10 effectively mitigates corrosion risk in UHPSSC by reducing the free chloride content by over 30% and achieving the lowest [Cl⁻]/[OH⁻] ratio (≈0.017), well below the corrosion threshold. This study establishes a solid theoretical framework for UHPSSC mix design and presents an innovative approach for controlling chloride-induced corrosion in marine concrete.

超高性能海水和海砂混凝土（UHPSSC）是一种极具应用前景的海洋工程材料。然而，由内部氯化物引起的钢筋腐蚀仍然是一个严峻的挑战。本研究旨在通过探索偏高岭土（MK）和富碱白泥浆（WM）作为补充胶凝材料的协同作用来调节UHPSSC中的氯化物结合并降低腐蚀风险，从而解决这一问题。研究了用MK代替硅灰，并加入10 wt。%和20 wt。% WM进入UHPSSC。分析了其力学性能、水化行为、微观结构和氯离子结合力。用MK完全替代硅灰，28天内抗压强度从131.5 MPa降低到123.6 MPa，而10 wt。% WM （WM10）抵消了这种减少，使强度增加3%。然而,20 wt。% WM导致显著的性能下降。微观结构分析表明，单独使用MK会破坏孔隙结构，而WM10则会增强火山灰反应，降低孔隙率。MK显著增加了氯化物的固定化，WM进一步加强了化学氯化物的结合，与常规UHPSSC相比，WM10在60天的化学结合氯化物数量几乎是其两倍。WM10通过减少30%以上的游离氯化物含量，达到最低的[Cl -⁻]/[OH -⁻]比（≈0.017），大大降低了UHPSSC的腐蚀风险，远低于腐蚀阈值。本研究为UHPSSC配合比设计建立了坚实的理论框架，并提出了一种控制海洋混凝土氯化物腐蚀的创新方法。

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引用次数: 0

Durability performance of natural rubber latex and high-volume fly ash incorporation in hybrid fibres concrete under aggressive environments 天然胶乳与高掺量粉煤灰掺入混合纤维混凝土在恶劣环境下的耐久性性能

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

Construction and Building Materials

Pub Date : 2026-04-11 Epub Date: 2026-03-09 DOI: 10.1016/j.conbuildmat.2026.145873

Hassaan Bin Tariq, Roszilah Hamid, A.B.M. Amrul Kaish, Shahrizan Baharom, Anis Azmi

This study investigates the combined effect of natural rubber latex (NRL) and high-volume fly ash (HVFA) on the durability performance of hybrid fibres concrete. Previous study has shown that incorporating 2.5% NRL and HVFA as cement replacement produces optimum mechanical properties of hybrid fibres concrete mix at 28 days (52 MPa - coded OM), compared to the control mix (56 MPa - coded CM). The specimens were then exposed to sulfuric acid (H₂SO₄, 5%), sodium sulphate (Na₂SO₄, 5%) and sodium chloride (NaCl, 3%) solutions. Results show that under acidic conditions, both mixes deteriorated severely, from 52 MPa and 56 MPa to 8 MPa and 9 MPa (180 days exposure). However, OM samples showed superior residual compressive strength, that is, higher 18%, 28%, and 17% at 56, 90, and 180 days exposure, respectively, and lower mass loss, less 20.5%, 68%, and 51.2%, compared to CM, complementing FESEM results showing pore refinement due to latex incorporation. Under sulphate and chloride exposures, both mixes show high resistance, with OM samples outperformed CM up to 90 days sulphate exposure, demonstrated through increased strength compared to 28 days strength and mass gain (peak 2.24% at 90 days – sulphate and 3.1% at 56 days - chloride) instead of mass loss. However, at 180 days, OM started to deteriorate, with reasonable strength losses (21% and 19%) but insignificant mass loses (1% and 0.3%) under sulphate and chloride, respectively. Physical observations confirmed volume changes in acid-exposed specimens, whereas no deterioration or significant volume change under sulphate and chloride environments.

研究了天然胶乳（NRL）和大掺量粉煤灰（HVFA）对混杂纤维混凝土耐久性的综合影响。先前的研究表明，与对照混合料（56 MPa -编码CM）相比，加入2.5% NRL和HVFA作为水泥替代品，混合纤维混凝土混合料在28天（52 MPa -编码OM）的力学性能最佳。然后将样品暴露于硫酸（H₂SO₄，5%）、硫酸钠（Na₂SO₄，5%）和氯化钠（NaCl, 3%）溶液中。结果表明，在酸性条件下，两种混合物均发生了严重的变质，从52 MPa和56 MPa到8 MPa和9 MPa （180 d）。然而，与CM相比，OM样品在56、90和180天的残余抗压强度分别高出18%、28%和17%，质量损失更低，分别低于20.5%、68%和51.2%，这与FESEM结果相补充，表明乳胶掺入导致孔隙细化。在硫酸盐和氯化物暴露下，这两种混合物都表现出很高的耐腐蚀性，OM样品在90天的硫酸盐暴露下表现优于CM，与28天的强度和质量增加（90天的峰值为2.24%，56天的峰值为3.1%）相比，质量损失有所增加。然而，在180 d时，OM开始变质，在硫酸盐和氯化物作用下，OM的强度损失（21%和19%）还算合理，但质量损失（1%和0.3%）并不明显。物理观察证实了酸暴露标本的体积变化，而在硫酸盐和氯化物环境下没有变质或显著的体积变化。

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引用次数: 0

Failure mechanisms and strength behaviour of foamed concrete under true triaxial compression 泡沫混凝土在真三轴压缩下的破坏机制和强度特性

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

Construction and Building Materials

Pub Date : 2026-04-11 Epub Date: 2026-03-11 DOI: 10.1016/j.conbuildmat.2026.145894

Hongzhi Zhang , Chuo Zhao , Nengdong Jiang , Shengyou Yang , Bo Li , Shu Liu , Zhi Ge

Foamed concrete is a lightweight and easily placed material with adjustable strength, which is promising for highway subgrade/backfill application. However, the uniaxial or conventional triaxial test cannot capture its behaviour under complex in-service multiaxial stress states. To this end, this study investigates the response of foamed concrete under true triaxial conditions with wet densities from 600 to 1000 kg/m³ under varied confining pressures. Stress-strain behaviours, energy dissipations, and failure modes were analysed, with an emphasis on the influence of the intermediate and minor principal stresses. Results show that confining pressure enhances the compressive strength, and the extent of the enhancement is determined by the ratio of the von Mises stress and the hydrostatic stress. Air void buckling dominates along the minor principal stress direction, whereas brittle shear failure prevails in both the intermediate and the minor principal stress direction. Finally, Miller’s yield criterion is shown to successfully predict the strength of foamed concrete under true triaxial loading. The scaling laws are proposed to correlate the peak stress, elastic strain energy ratio, and Miller’s model parameters with porosity. The study contributes to the knowledge of the mechanical behaviour of foamed concrete under a true triaxial stress state.

泡沫混凝土是一种重量轻、易于放置、强度可调的材料，在公路路基/回填中应用前景广阔。然而，单轴或传统的三轴试验不能捕捉其在复杂的多轴应力状态下的行为。为此，本研究考察了湿密度为600 ~ 1000 kg/m³ 的泡沫混凝土在真三轴条件下在不同围压下的响应。分析了应力-应变行为、能量耗散和破坏模式，重点分析了中主应力和小主应力的影响。结果表明，围压提高了混凝土的抗压强度，其增强程度由von Mises应力与静水应力之比决定。沿小主应力方向以气孔屈曲为主，中主应力方向和小主应力方向均以脆性剪切破坏为主。最后，Miller屈服准则成功地预测了泡沫混凝土在真三轴荷载作用下的强度。提出了峰值应力、弹性应变能比和米勒模型参数与孔隙率之间的标度规律。该研究有助于了解泡沫混凝土在真三轴应力状态下的力学行为。

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引用次数: 0

Eco-efficient sodium alginate-enhanced MICP for graphite tailings stabilization: Mechanical performance and weathering resistance 生态高效海藻酸钠增强石墨尾矿稳定MICP：机械性能和耐风化性

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

Construction and Building Materials

Pub Date : 2026-04-11 Epub Date: 2026-03-11 DOI: 10.1016/j.conbuildmat.2026.145930

Huijie Huang , Xin Xu , Qing Wang , Xiaoqing Yuan , Huiting Gao , Qirui Zheng

With the expansion of mining activities, the long-term open storage of tailings produced in the process of mineral processing has become an important source of dust pollution and environmental risk in mining areas, posing potential threats to the stability of ecosystem and human health. Microbially induced calcium carbonate precipitation (MICP) is a promising green solidification technology; however, its long-term stability and solidification performance remain to be improved. In this study, sodium alginate (SA), a naturally degradable polysaccharide, was introduced as a bioenhancer for MICP. The effects of SA dosage on urease activity, CaCO₃ content, mechanical strength, and resistance to wind and rainfall erosion were systematically investigated. The underlying synergistic solidification mechanisms of the SA–MICP process were elucidated by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The results demonstrate that SA exhibits a pronounced concentration "window effect", achieving optimal curing performance at a 1.5% dosage. The urease activity reaches 162.5 U/L with 61.8% CaCO3 content. Compared to SA-free samples, the unconfined compressive strength and splitting tensile strength increase by 1.22-fold and 3.95-fold respectively. Meanwhile, the UCS/STS ratio drops significantly from 6.26 to 2.81, indicating that SA primarily enhances interfacial bonding and crack resistance. Additionally, the material shows marked improvements in surface hardness, Young's modulus, wind erosion resistance, and rain erosion resistance. Microstructural analyses indicated that SA facilitated Ca^2 + chelation via its carboxyl groups, promoting oriented CaCO₃ nucleation and the formation of an organic–inorganic composite cementation network, thereby increasing the homogeneity and compactness of the precipitate structure. In contrast, excessive SA (>3%) hindered mass transfer and led to nonuniform precipitation, reducing the solidification efficiency. Overall, this work demonstrates that the SA–MICP synergistic approach can markedly increase the strength and environmental durability of tailings, offering a green and efficient strategy for dust control and ecological restoration in mining areas and providing theoretical and engineering foundations for MICP applications under extreme climatic conditions.

随着矿山开采规模的扩大，矿物加工过程中产生的尾矿长期露天贮存已成为矿区扬尘污染和环境风险的重要来源，对生态系统的稳定和人体健康构成潜在威胁。微生物诱导碳酸钙沉淀（MICP）是一种很有前途的绿色固化技术；但其长期稳定性和凝固性能有待提高。在本研究中，海藻酸钠（SA）是一种天然可降解的多糖，被引入作为MICP的生物增强剂。系统研究了SA用量对脲酶活性、CaCO3含量、机械强度和抗风蚀性的影响。利用扫描电镜（SEM）、x射线衍射（XRD）和傅里叶变换红外光谱（FTIR）分析了SA-MICP过程的协同凝固机制。结果表明，SA表现出明显的浓度“窗口效应”，在1.5%的掺量下获得最佳的固化性能。脲酶活性达到162.5 U/L， CaCO3含量为61.8%。与不含sa的试样相比，无侧限抗压强度和劈裂抗拉强度分别提高了1.22倍和3.95倍。同时，UCS/STS比值从6.26显著下降到2.81，说明SA主要增强了界面结合和抗裂性。此外，该材料在表面硬度、杨氏模量、抗风蚀性和抗雨蚀性方面均有显著改善。微观结构分析表明，SA通过其羧基促进Ca2 +的螯合作用，促进CaCO3定向成核，形成有机-无机复合胶结网络，从而提高了沉淀结构的均匀性和致密性。相反，过量的SA （>3%）阻碍了传质，导致析出不均匀，降低了凝固效率。总体而言，本研究表明，SA-MICP协同方法可以显著提高尾矿的强度和环境耐久性，为矿区粉尘治理和生态修复提供了绿色高效的策略，为MICP在极端气候条件下的应用提供了理论和工程基础。

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引用次数: 0

Influence of molar ratio on properties of MgO-hydromagnesite binder 摩尔比对氧化镁-氢菱镁矿粘结剂性能的影响

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

Construction and Building Materials

Pub Date : 2026-04-11 Epub Date: 2026-03-10 DOI: 10.1016/j.conbuildmat.2026.145863

Zhen Li , Lulu Zhang , Zhongcheng Li , Yongbo Huang , Hao Tang , Jueshi Qian

The performance and quality of MgO-based cement largely depend on the molar ratio of its constituent reactants. The MgO-hydromagnesite (MgO-HY) system is a new type of low-carbon MgO-based cementitious material, but the influence of the key component ratio of MgO/hydromagnesite on its performance has not yet been studied. To clarify the performance characteristics of the MgO-HY system and optimize its composition ratio, this study investigates the MgO/hydromagnesite molar ratio (e.g. 8/1,16/1, 32/1, 64/1, 96/1 and 128/1) on properties of MgO-HY paste and mortar. The fluidity, setting time, compressive strength, dimensional stability, bulk density and permeable porosity of MgO-HY binder are tested. Mortar specimens with varying water-binder ratios are prepared and tested to evaluate their mechanical performance. The phase formation and micromorphology are analyzed to correlate microstructural development with macroscopic properties. Results demonstrate that higher MgO/hydromagnesite ratio promote the generation of hydrous carbonate containing brucite (HCB), which accelerates setting, improves strength and reduces drying shrinkage. However, beyond a molar ratio of 96/1, the effectiveness of HCB in filling pore space diminishes due to reduced crystal size, leading to decreased strength and slightly increased shrinkage. Optimal performance, characterized by high strength and minimal shrinkage, is observed within the molar ratio range of 32/1–96/1. Additionally, lowering the water-binder ratio significantly enhances mortar strength, achieving a maximum value of 51.8 MPa.

mgo基水泥的性能和质量在很大程度上取决于其组成反应物的摩尔比。MgO-氢菱镁矿（MgO- hy）体系是一种新型的低碳MgO基胶凝材料，但MgO/氢菱镁矿关键组分配比对其性能的影响尚未研究。为了明确MgO- hy体系的性能特点并优化其组成比例，本研究考察了MgO/氢菱镁矿摩尔比（如8/1,16/ 1,32 / 1,64 / 1,96 /1和128/1）对MgO- hy膏体和砂浆性能的影响。测试了MgO-HY粘结剂的流动性、凝结时间、抗压强度、尺寸稳定性、体积密度和渗透孔隙率。制备了不同水胶比的砂浆试件，并对其力学性能进行了测试。分析了相形成和微观形貌，将微观结构的发展与宏观性能联系起来。结果表明：较高的氧化镁/氢菱镁矿比促进含水镁石碳酸盐（HCB）的生成，加速了凝固，提高了强度，减少了干燥收缩率；然而，当摩尔比超过96/1时，由于晶体尺寸减小，HCB填充孔隙空间的有效性减弱，导致强度下降，收缩率略有增加。在32/1 ~ 96/1的摩尔比范围内，具有高强度和最小收缩率的最佳性能。降低水胶比显著提高砂浆强度，砂浆强度最大值为51.8 MPa。

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引用次数: 0

The effects of sodium citrate, sodium tripolyphosphate and the plant protein on properties of 3D printing gypsum-based materials: Retardation mechanism at ultralow content 柠檬酸钠、三聚磷酸钠和植物蛋白对3D打印石膏基材料性能的影响：超低含量下的阻滞机理

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

Construction and Building Materials

Pub Date : 2026-03-21 Epub Date: 2026-02-20 DOI: 10.1016/j.conbuildmat.2026.145685

Xinxin Yu , Kai Ma , Xingyu Gan , Yali Li , Laibo Li , Haiming Zhang , Lingchao Lu

Retarders are indispensable admixtures for ensuring sufficient printability time of 3D printing gypsum-based materials. However, a well-established fact related to high retarder content that excessive retarder content can reduce the mechanical properties of gypsum pastes. Therefore, the crucial strategy for expanding the application of 3D printing gypsum-based materials is to achieve efficient retarder at ultralow content. This study systematically analyzed the mechanisms of sodium citrate, sodium tripolyphosphate, and the plant protein retarder on gypsum-based 3D printing materials at ultralow content by workability, mechanical properties, and microstructure test. The results demonstrated that the plant protein retarder exhibited optimal performance in enhancing the workability and mechanical properties of the paste. When the content of this retarder was 0.4 ‰, the initial setting time of the gypsum paste was extended from 7 min to 56 min, while increasing the 7-day compressive and flexural strengths of the gypsum specimens by 81.63 % and 47.19 %, respectively. Mechanistically, the three retarders differed in gypsum particle adsorption due to distinct anionic structures, regulating setting time differently. These retarders complexed with Ca^2 + to form insoluble compounds, reducing hemihydrate gypsum dissolution and transforming dihydrate gypsum crystals from elongated prisms to plate-like structures. Enhanced crystal interlocking reduced hardened paste porosity, ultimately improving mechanical strength.

缓速剂是保证3D打印石膏基材料有足够的打印时间不可缺少的外加剂。然而，缓凝剂含量过高会降低石膏膏的力学性能，这是一个公认的事实。因此，实现高效的超低含量缓凝剂是扩大石膏基材料3D打印应用的关键策略。本研究通过和易性、力学性能和微观结构测试，系统分析了柠檬酸钠、三聚磷酸钠和植物蛋白缓凝剂对超低含量石膏基3D打印材料的作用机理。结果表明，植物蛋白缓凝剂在提高浆料的可加工性和力学性能方面表现最佳。当掺量为0.4 ‰时，石膏膏体的初凝时间由7 min延长至56 min，试件抗压强度和抗弯强度分别提高81.63 %和47.19 %。在机理上，由于阴离子结构不同，三种缓凝剂对石膏颗粒的吸附不同，对凝结时间的调节也不同。这些缓凝剂与Ca2 +络合形成不溶性化合物，减少了半水石膏的溶解，并将二水石膏晶体从细长的棱镜转变为板状结构。增强的晶体互锁减少了硬化膏体的孔隙率，最终提高了机械强度。

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引用次数: 0

Prestressed high-strength high-modulus engineered cementitious composites towards resilient infrastructures 面向弹性基础设施的预应力高强高模量工程胶凝复合材料

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

Construction and Building Materials

Pub Date : 2026-03-21 Epub Date: 2026-02-20 DOI: 10.1016/j.conbuildmat.2026.145607

Ziming Tang , Yao Ding , Gang Liao , Fei Wang , Long Liang , Victor C. Li , Kequan Yu

High-strength and High modulus Engineered Cementitious Composites (HSHM-ECC) features excellent tensile ductility, high tensile/compressive strength and elastic modulus. Prestressing technology can effectively improve the crack resistance performance, durability and load-bearing capacity of concrete structures. It is expected that the application of HSHM-ECC in the prestressed systems will further enhance the structural durability and ductility. In this research, a HSHM-ECC with elastic modulus exceeding 45 GPa, 28-day drying shrinkage less than 400 με, 120-day creep coefficient less than 0.5 and chloride diffusion coefficient of 0.04 × 10⁻¹² m²/s was developed. The local compression characteristics of HSHM-ECC were investigated and a novel prestressed HSHM-ECC composite beam system was then proposed. The flexural and shear performance of prestressed HSHM-ECC beams were preliminarily evaluated, which revealed superior structural performances over the prestressed mortar and UHPC beams at serviceability and/or ultimate limit states. The cracking load and bearing capacity of prestressed HSHM-ECC beams under the serviceability limit state have increased by 107.1 % and 23.1 % respectively compared with those of ordinary HSHM-ECC beams. The energy absorption of prestressed HSHM-ECC beams was increased by 284.4 %, 384.1 % and 101.0 % respectively compared with that of prestressed mortar beam, prestressed UHPC beam and ordinary HSHM-ECC beams. This paper demonstrates the feasibility of prestressed HSHM-ECC components based on the tests at both material and structural component levels. The proposed prestressed HSHM-ECC composite components have application potential for bridges, industrial buildings, railway sleepers and marine structures (e.g., exploration platforms and floating structures) with enhanced structural resilience.

高强高模量工程胶凝复合材料（HSHM-ECC）具有优异的拉伸延展性，高抗拉/抗压强度和弹性模量。预应力技术可以有效地提高混凝土结构的抗裂性能、耐久性和承载能力。预计HSHM-ECC在预应力体系中的应用将进一步提高结构的耐久性和延性。本研究制备了弹性模量大于45 GPa、28 d干燥收缩率小于400 με、120 d蠕变系数小于0.5、氯离子扩散系数为0.04 × 10−12 m2/s的HSHM-ECC。研究了HSHM-ECC的局部压缩特性，提出了一种新型预应力HSHM-ECC组合梁体系。对预应力HSHM-ECC梁的抗弯抗剪性能进行了初步评价，表明其在使用和极限状态下的结构性能优于预应力砂浆和UHPC梁。在使用极限状态下，预应力HSHM-ECC梁的开裂荷载和承载力比普通HSHM-ECC梁分别提高了107.1 %和23.1 %。与预应力砂浆梁、预应力UHPC梁和普通HSHM-ECC梁相比，预应力HSHM-ECC梁的吸能分别提高284.4 %、384.1 %和101.0 %。本文从材料和构件两个层面的试验，论证了预应力HSHM-ECC构件的可行性。提出的预应力HSHM-ECC复合构件在桥梁、工业建筑、铁路枕木和海洋结构（如勘探平台和浮式结构）中具有增强结构回弹性的应用潜力。

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引用次数: 0

Experimental and analytical evaluation of crumb rubber concrete with multi-blended industrial waste aggregate and SCMs: Strength, durability, microstructure, and ML prediction 工业废骨料与SCMs混合橡胶颗粒混凝土的试验与分析评价：强度、耐久性、微观结构和ML预测

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

Construction and Building Materials

Pub Date : 2026-03-21 Epub Date: 2026-02-23 DOI: 10.1016/j.conbuildmat.2026.145677

Subham Mishra , Swetapadma Panda , Debashis Bhowmik , Sayantan Guha

Rubberized concrete offers notable environmental benefits through waste tire utilization; however, its application is constrained by comparatively low mechanical strength. The addition of suitable industrial waste materials may offer a viable strategy to offset the strength reduction and improve the structural performance of rubberized concrete. Consequently, researchers are investigating supplemental cementitious materials (SCMs) as alternatives to conventional binders and industrial waste materials as substitutes for fine aggregates in the construction industry. This study proposes a framework to improve the properties of blended crumb rubber concrete (BCRC) incorporating industrial by-products such as copper slag (CS) and steel slag (SS) as fine aggregates, along with silica fume (SF) and rice husk ash (RHA) as SCMs. Four types of BCRC mixes were investigated for fresh concrete properties, mechanical properties through compressive, split tensile, and flexural strengths, as well as durability indicators like alkali–silica reaction (ASR) and rapid chloride penetration test (RCPT). Out of all mixes, BCRC4 (20 %CR+20 %SF+10 %RHA+20 %CS+10 %SS) shows the 54 % improved strength and durability properties that resulted from balanced use of SCMs and industrial waste materials. However, predicting the compressive strength of BCRC remains complex due to its heterogeneous composition and age-dependent behavior. To address this, seven widely used machine-learning techniques were employed to estimate compressive strength at advanced curing ages, including linear regression, decision tree, random forest, extreme gradient boosting (XGBoost), support vector machine (SVM), and Lloyd’s algorithm (K-means clustering). Model performance was evaluated using regression analysis and statistical indicators. Among the models, linear regression demonstrated the highest predictive accuracy, achieving an R² value of 0.94 with the lowest mean squared error (0.39) and mean absolute error (0.48). Furthermore, SHAP (SHapley Additive exPlanations) analysis was conducted for the optimal BCRC4 mix to interpret the contribution of individual input variables, providing valuable insights into the influence of alternative fine aggregates and SCMs on compressive strength development with curing age.

橡胶混凝土通过对废旧轮胎的利用，具有显著的环境效益；但其机械强度较低，制约了其应用。添加合适的工业废料可以提供一个可行的策略，以抵消强度降低，提高橡胶混凝土的结构性能。因此，研究人员正在研究补充胶凝材料（SCMs）作为传统粘合剂的替代品和工业废料作为建筑行业细骨料的替代品。本研究提出了一个框架来改善混合橡胶屑混凝土（BCRC）的性能，该混凝土采用工业副产品，如铜渣（CS）和钢渣（SS）作为细骨料，以及硅灰（SF）和稻壳灰（RHA）作为细骨料。研究了四种BCRC混合料的新拌混凝土性能、抗压、劈裂拉伸和抗弯强度的力学性能，以及碱-硅反应（ASR）和快速氯化物渗透试验（RCPT）等耐久性指标。在所有混合料中，BCRC4（20 %CR+20 %SF+10 %RHA+20 %CS+10 %SS）显示出54 %的强度和耐久性提高，这是由于平衡使用scm和工业废料。然而，预测BCRC的抗压强度仍然很复杂，因为它的异质性组成和年龄依赖性行为。为了解决这个问题，研究人员采用了7种广泛使用的机器学习技术来估计高龄养护时的抗压强度，包括线性回归、决策树、随机森林、极端梯度增强（XGBoost）、支持向量机（SVM）和劳埃德算法（K-means聚类）。采用回归分析和统计指标对模型性能进行评价。其中，线性回归模型的预测精度最高，R²值为0.94，均方误差（0.39）和平均绝对误差（0.48）最低。此外，对最佳BCRC4混合料进行了SHAP （SHapley Additive exPlanations）分析，以解释各个输入变量的贡献，为细骨料和细颗粒对抗压强度随养护龄期发展的影响提供了有价值的见解。

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引用次数: 0

Corrigendum to “Study on the meso-scale numerical simulation method for flow behavior of fresh self-compacting steel fiber reinforced concrete based on DEM-SPH coupling” [Constr. Build. Mater. 496 (2025) 143804] “基于DEM-SPH耦合的新鲜自密实钢纤维混凝土流动特性的中尺度数值模拟方法研究”[j]。构建。Mater. 496 (2025) 143804]

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

Construction and Building Materials

Pub Date : 2026-03-21 Epub Date: 2026-02-16 DOI: 10.1016/j.conbuildmat.2026.145635

Xinxin Ding , Wenlei Jia , Changyong Li , Haibin Geng , Gonglian Chen , Shunbo Zhao

引用次数: 0

Carbonation behavior and mechanical performance of low-carbon recycled concrete under different CO2 pressures 不同CO2压力下低碳再生混凝土的碳化行为及力学性能

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

Construction and Building Materials

Pub Date : 2026-03-21 Epub Date: 2026-02-20 DOI: 10.1016/j.conbuildmat.2026.145684

Hao Bao , Jie Wang , Gang Xu , Ruyu Wang , Mohamed Saafi , Jianqiao Ye

The construction industry faces challenges from high cement-related carbon emissions and construction waste. To address carbon reduction, sequestration, and waste utilization, accelerated carbonation tests were conducted on low-carbon recycled concrete (LCRC) to evaluate the effects of recycled aggregate (RA) replacement ratio of natural aggregate (NA), cement replacement ratio by ground granulated blast-furnace slag (GGBS), and external CO₂ pressure on carbonation depth and compressive strength. Microstructural analyses (SEM, EDX, MIP, and TGA-DSC) were conducted to analyze the microstructure, elemental distribution, pore structure, and compositional changes in LCRC before and after carbonation. Results showed that the LCRC carbonation depth increased and the compressive strength decreased with the increase of the RA and cement replacement ratios. The elevated external CO₂ pressure significantly accelerated carbonation, enhancing both carbonation depth and compressive strength. Under supercritical condition (7.5 MPa), the carbonation depth of the LCRC increased by an average of 164 % compared to samples at 0.1 MPa, while the average compressive strength was 47 % higher than that of the uncarbonated samples. Carbonation converts flocculent C-S-H gel into CaCO₃, refining the pore structure and reducing porosity by 28–34 %. Based on the TGA result difference inversion, a method for determining Ca(OH)₂ and C-S-H contents in LCRC was proposed, revealing pre-carbonation contents of 17–37 % and 63–83 %, respectively. The maximum carbon uptake capacity reached 96.09 kg CO₂/m³ of LCRC, highlighting its potential to support a low-carbon circular concrete industry.

建筑行业面临着与水泥相关的高碳排放和建筑垃圾的挑战。为解决碳减排、固碳和废弃物利用问题，对低碳再生混凝土（LCRC）进行了加速碳化试验，评价了再生骨料（RA）对天然骨料（NA）的替代率、磨粒矿渣（GGBS）对水泥的替代率以及外部CO2压力对碳化深度和抗压强度的影响。通过SEM、EDX、MIP和TGA-DSC等微观结构分析，分析碳化前后LCRC的微观结构、元素分布、孔隙结构和组分变化。结果表明：随着RA和水泥替代率的增加，LCRC碳化深度增加，抗压强度降低；外部CO2压力的升高显著加速了碳酸化，提高了碳酸化深度和抗压强度。在超临界条件下（7.5 MPa）， LCRC的碳化深度比0.1 MPa时平均增加164 %，抗压强度比未碳化时平均提高47 %。碳化作用将絮凝剂C-S-H凝胶转化为CaCO3，改善了孔隙结构，孔隙率降低了28 - 34% %。基于TGA结果差值反演，提出了一种测定LCRC中Ca(OH)2和C-S-H含量的方法，其预碳化含量分别为17-37 %和63-83 %。LCRC的最大碳吸收能力达到96.09 kg CO2/m3，突出了其支持低碳循环混凝土产业的潜力。

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