Construction and Building Materials最新文献

{"title":"Research on physical and mechanical properties of alkaline-modified self-compacting rubber concrete","authors":"Pan Ming ,&nbsp;Shenghua Ye ,&nbsp;Jun Lu ,&nbsp;Jiang Yu ,&nbsp;Miaoyan Liu ,&nbsp;Guofu Zhao ,&nbsp;Xudong Chen","doi":"10.1016/j.conbuildmat.2025.142251","DOIUrl":"10.1016/j.conbuildmat.2025.142251","url":null,"abstract":"<div><div>This paper presents an alkaline-modified method to enhance the performance of self-compacting rubber concrete (SCRC). Physical and mechanical properties of modified SCRC are analyzed. The results show that after limestone immersion, improved the surface properties of the rubber particles and attached alkaline-excited Ca(OH)₂, which induced an earlier volcanic ash reaction in the cementitious and auxiliary cementitious materials. This resulted in the generation of hydrated calcium-silica hydrate (CSH) between the rubber particle and the matrix, enhancing the adhesion and interfacial strength between them. And the generation of hydrated CSH fill the pores, resulting in a reduction of the SCRC connecting pores. The modified SCRC density increases and water absorption decreases. The rate of charge exchange slows down in a chloride ion environment. The resistivity of the modified SCRC increased by approximately 20 %. When the rubber content is 5 %, 10 % and 15 %, the compressive strength of the modified SCRC is enhanced by 6.9 %, 8.1 % and 11.7 %, and the flexural tensile strength by 9.0 %, 16.8 % and 23.1 % respectively. The modulus of elasticity is enhanced by 9.8 %, 9.2 % and 13.5 %, and threshold stress levels at the point of elasticity are improved by 10.5 %, 4.5 % and 6.1 % respectively. During compression, the fracture activity and the energy released reduced. And the fatigue life is significantly increased for the same compression fatigue strength. However, after modification, the pre-peak compressive toughness index decreased by 24.1 %, 24.6 % and 9.2 %, and the pre-peak bending and tensile toughness index decreased by 34.4 %, 15.4 % and 25.8 %, respectively. Consequently, it can be found that the modified SCRC durability and strength are improved, but the SCR toughness is reduced.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"489 ","pages":"Article 142251"},"PeriodicalIF":7.4,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144263461","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental in-situ characterisation of the damping properties of road pavements","authors":"G. Loi ,&nbsp;M.C. Porcu ,&nbsp;F. Maltinti ,&nbsp;M. Coni ,&nbsp;F. Aymerich","doi":"10.1016/j.conbuildmat.2025.142174","DOIUrl":"10.1016/j.conbuildmat.2025.142174","url":null,"abstract":"<div><div>Vibrations induced by tyre/pavement interaction may be of concern for the underlying structure and, due to propagation of waves, for surroundings buildings and facilities. In addition, they may cause discomfort to drivers and passengers of vehicles, as well as traffic noise pollution. Improving damping properties of roads may mitigate most of the harmful traffic-induced effects. Nevertheless, the evaluation of damping properties of road systems is still an open issue. The present paper aims to contribute to this matter by assessing the effectiveness of two procedures for the in-situ characterisation of road pavement damping. The first procedure (MDPE-SD) evaluates the damping properties of physical vibration modes by means of a modal parameter identification algorithm used in association with stabilisation diagrams. The second procedure (CWT-ED) applies a wavelet transform for frequency decoupling and estimates damping by evaluating the rate of signal decay. In-situ tests, in which an instrumented hammer and an accelerometer were used respectively to apply an impact load and to measure the vibration response, were conducted on flexible and rigid pavements. The reliability of the two experimental procedures was assessed and compared by examining the damping ratios estimated for the two pavements at different frequencies and for different excitation and sensing locations. The investigation indicated that the spectral response of the pavements was characterised by multiple closely spaced modes, thus affecting the reliability of their identification through the MDPE algorithm. The analyses also showed that the damping ratios provided by the MDPE-SD procedure may be greatly affected by the choice of the excitation and sensing locations. In contrast, the CWT-ED procedure was much more robust, at any of the frequencies considered for the two pavement systems tested, to changes in the excitation and sensing sites, thus highlighting its superior capability to estimate the damping properties of road pavements.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"489 ","pages":"Article 142174"},"PeriodicalIF":7.4,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144261301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of grids on the tensile and flexural behavior of hybrid fiber high performance concrete","authors":"Zhu Bian ,&nbsp;Yi Han ,&nbsp;Liting Du ,&nbsp;Jiachen Gao ,&nbsp;Zhenghua Zhou ,&nbsp;Liguo Jin","doi":"10.1016/j.conbuildmat.2025.142242","DOIUrl":"10.1016/j.conbuildmat.2025.142242","url":null,"abstract":"<div><div>To identify suitable retrofitting materials for enhancing structural performance, four types of grids were integrated into hybrid fiber high-performance concrete (HyFHPC), which is a high-performance concrete mixed with two types of short fibers—steel fibers and PE fibers. A comprehensive experimental program tested 20 composite plate series, grouped into plain high-performance concrete (HPC), grid-reinforced HPC (GR-HPC), HyFHPC, and grid-reinforced HyFHPC (GR-HyFHPC). Uniaxial tensile and four-point bending tests were conducted on all specimens to investigate the influence of matrix type, grid type, and grid layer on the mechanical properties and failure characteristics of the composites. The comprehensive energy dissipation index was introduced to thoroughly quantify the properties of composites under tensile and bending conditions. Digital image correlation (DIC) technology was utilized to analyze the crack and strain evolution. Results indicated that the addition of grids mitigated the brittleness of HPC, although the bonding between them was weak. All GR-HyFHPC combinations exhibited enhanced strength, deformation, and bonding capabilities. The comprehensive energy dissipation index provided a scientific and convenient method for assessing the performance of the composites. DIC technology accurately captured crack evolution and strain distribution, offering an intuitive platform for analyzing specimen behavior. Overall, the GR-HyFHPC combinations demonstrated remarkable performance in terms of strength and ductility, highlighting their comprehensive energy dissipation capacity and showing significant potential for structural retrofitting applications.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"489 ","pages":"Article 142242"},"PeriodicalIF":7.4,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144263455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on corrosion and mechanical properties of railway steel in industrial atmosphere","authors":"Mengtian Fan ,&nbsp;Yue Li ,&nbsp;Fei Wang ,&nbsp;Hongwei Fang ,&nbsp;Zengzhi Qian","doi":"10.1016/j.conbuildmat.2025.142253","DOIUrl":"10.1016/j.conbuildmat.2025.142253","url":null,"abstract":"<div><div>Salt spray tests were conducted to simulate the corrosion behavior of Q345, Q370, and Q500qENH steels under industrial atmospheric conditions. The experiments included five corrosion cycles: 2, 4, 8, 18, and 30 days. The weight loss of steel under various corrosion cycles was calculated using the corrosion weight loss method. Based on the experimental data, the corrosion rate of steel was analyzed to investigate the corrosion kinetics. The corrosion morphology and elemental content of the rust layer were analyzed using scanning electron microscopy (SEM) and an energy-dispersive spectrometer (EDS). The composition of the rust layer was analyzed by X-ray diffraction (XRD) under different corrosion durations. The surface roughness of the steel, after rust removal, was measured with a confocal scanning microscope. Additionally, the Tafel curve and electrochemical impedance of the rust layer were evaluated using electrochemical methods. Finally, the relationship between corrosion time and degradation of mechanical properties of steel sheet was investigated by static stretching of steel sheet with varying corrosion periods. The results indicate that the corrosion rates of Q345, Q370, and Q500qENH in an industrial atmospheric environment consistently decrease as corrosion time increases. This reduction in corrosion rate is primarily due to the increased presence of structurally dense corrosion product α-FeOOH. The corrosion rate of Q500qENH is comparable to that of Q345 and Q370 during the early stage; however, it is significantly lower than the rates of the other two in the later stage. As the corrosion time increases, both the area and depth of corrosion pits on the surface of the three types of steel continue to expand. Ultimately, a relationship between mechanical parameters and corrosion age is established, revealing a linear decrease.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"489 ","pages":"Article 142253"},"PeriodicalIF":7.4,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144271134","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimizing fiber type and content in geopolymer–oil composites: A multi-criteria performance analysis","authors":"Yunus Seyrek ,&nbsp;Ognjen Rudic ,&nbsp;Joachim Juhart ,&nbsp;Marcella Ruschi Mendes Saade ,&nbsp;Cyrill Grengg ,&nbsp;Bernhard Freytag ,&nbsp;Florian Mittermayr","doi":"10.1016/j.conbuildmat.2025.142218","DOIUrl":"10.1016/j.conbuildmat.2025.142218","url":null,"abstract":"<div><div>This study explores the effects of different fiber types and volume fractions on the performance of vegetable oil-modified geopolymer composites, with a specific focus on crack control, mechanical properties, environmental impact, and cost-effectiveness. The influence of various types of fibers, namely three types of basalt fibers (dispersible, alkali-resistant, and uncoated), polypropylene, glass, hemp, and cellulose fibers, was evaluated at 0.5 %, 1 %, 1.5 %, and 2 % volume fractions. The assessment covered spread flow, compressive and splitting tensile strength, crack formation, environmental impact, and costs. Among all fiber types, uncoated basalt (UCB) fibers demonstrated the most significant mechanical enhancement, increasing compressive strength by up to 17 % and splitting tensile strength by approximately 30 % compared to the reference mix, while reducing drying shrinkage crack width by nearly 80 %. Cellulose fibers effectively minimized crack number and exhibited the lowest global warming potential (0.06 kg CO₂-eq/kg). A multi-criteria decision analysis identified cellulose fibers at 1.5 % volume fraction as the optimal choice, closely followed by UCB fibers. These findings provide practical insights for designing sustainable, durable, and low-carbon repair mortars and sewer system linings, particularly in aggressive environments where crack resistance and environmental performance are critical.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"489 ","pages":"Article 142218"},"PeriodicalIF":7.4,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144271132","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A new design concept for high-content phosphogypsum cementitious materials: From packing model to microstructural optimization","authors":"Zhengkang Yu ,&nbsp;Zhijie Liu ,&nbsp;Chiqiu Wu ,&nbsp;Wei Lv ,&nbsp;Jing He ,&nbsp;Yisheng Li ,&nbsp;Zhonghe Shui","doi":"10.1016/j.conbuildmat.2025.142165","DOIUrl":"10.1016/j.conbuildmat.2025.142165","url":null,"abstract":"<div><div>Phosphogypsum (PG) faces significant challenges in resource utilization due to its large-scale production and limited applications. This study aims to develop high-content phosphogypsum cementitious materials (HPCM) containing over 70 % PG, along with small amounts of supplementary cementitious materials (SCMs) and cement. A novel packing model is proposed, incorporating the particle size and morphology characteristics of solid particles in HPCM. The Box-Behnken design (BBD) is employed to evaluate the effects of key model parameters on the packing density (PD) of HPCM. On this basis, metakaolin (MK) is used to optimize the packing structure of PG, SCMs, and cement, and the optimal mix proportion for HPCM is determined. The study investigates the effects of SCMs composition and compacting pressure on HPCM’s physical properties, mechanical strength, hydration products and microstructure. The particle gradation of SCMs significantly influences the PD of HPCM. The 28d compressive strength of HPCM reaches a maximum of 68.8 MPa when the MK content is 5 % and the compacting pressure is 60 MPa. This optimal MK content optimizes the pore structure and minimizes PG recrystallization, reducing crack formation. When the MK content exceeds 5 %, the formation of hydration products decreases, and this reduction becomes more significant under higher compacting pressure. Excessive pressure reduces PG recrystallization but limits hydration product development, causing matrix expansion. The study offers a novel approach for optimizing the mix design of HPCM, contributing to sustainable resource utilization and environmental protection.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"489 ","pages":"Article 142165"},"PeriodicalIF":7.4,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144263457","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bond properties and predictive modeling of steel reinforcement and steel fiber reinforced concrete (SFRC) under chloride ion attack","authors":"Haotian Liu ,&nbsp;Lin Yang ,&nbsp;Zongze Li ,&nbsp;Dong Fang ,&nbsp;Guowen Sun ,&nbsp;Ying Li ,&nbsp;Danying Gao","doi":"10.1016/j.conbuildmat.2025.142207","DOIUrl":"10.1016/j.conbuildmat.2025.142207","url":null,"abstract":"<div><div>This study systematically reveals the evolution of bond-slip properties between steel reinforcement and steel fiber reinforced concrete (SFRC) under chloride ion erosion. It quantifies the crack-suppressing effect of fibers in concrete and the deteriorating effect of corrosion-induced expansion, establishing a mapping relationship between water-cement ratio (0.3 −0.5), steel fiber content (0 −1.5 %), and bond strength. Results show an optimal range for steel fiber content in chloride environments. After corrosion, specimens with 0 %, 0.5 %, 1.0 %, and 1.5 % steel fibers exhibited bond strength changes of −99.2 %, + 5.6 %, + 19.7 %, and −13.2 %, respectively. Reducing the water-cement ratio effectively improves reinforcement-SFRC bonding and inhibits performance deterioration in corrosive environments. Additionally, an evolution and prediction model for rebar-SFRC bonding performance was developed, incorporating chloride corrosion time. This study provides a quantitative basis for durability design and life prediction of SFRC structures in offshore engineering, particularly in optimizing steel fiber dosage and water-cement ratio control, offering significant engineering guidance value.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"489 ","pages":"Article 142207"},"PeriodicalIF":7.4,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144263452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical activation of muscovite-rich clay: A novel approach for ternary blended cement","authors":"Jofre Mañosa ,&nbsp;Alex Maldonado-Alameda ,&nbsp;Josep Maria Chimenos","doi":"10.1016/j.conbuildmat.2025.142182","DOIUrl":"10.1016/j.conbuildmat.2025.142182","url":null,"abstract":"<div><div>Clay minerals with a 2:1 structure typically exhibit limited pozzolanic activity after calcination, which constrains their use as supplementary cementitious materials. Mechanical activation has emerged as a promising approach to enhance the reactivity of clays, potentially improving the performance of cement containing mixed clays rich in 2:1 clay minerals. This research assesses the properties of ternary blended cement produced with mechanically activated muscovite-rich mixed clay (LMC²-MM) in comparison to limestone calcined clay cement containing either calcined muscovite-rich mixed clay (LC³-CM) or metakaolin (LC³-MK). Results from pozzolanic activity tests (R³ and modified Chapelle) revealed a significant improvement in the reactivity of muscovite-rich mixed clay via mechanical activation (MM) compared to thermal activation (CM). LMC²-MM exhibited similar structure and properties to conventional LC³-MK, and the enhanced reactivity of MM over CM led to improved properties for LMC²-MM compared to LC³-CM. The hydration of LMC²-MM was superior to that of LC³-CM, achieving significantly refined porosity at both 3 and 28 days. This study presents a novel approach to ternary blended cement by incorporating mechanically activated mixed clay. It demonstrates that mechanical activation enhances the properties of blended cement, particularly at early ages when using muscovite-rich clays, achieving compressive strength comparable to conventional LC³ with metakaolin. The mechanical activation of muscovite-rich mixed clay presents a promising strategy for using local clay resources in regions where kaolinite-rich clay is scarce.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"489 ","pages":"Article 142182"},"PeriodicalIF":7.4,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144271018","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of various SCMs on the properties of mortar systems during steam and carbonation curing conditions","authors":"Yizhe HeLian ,&nbsp;Jiaxin Liao ,&nbsp;Yonghui Zhang ,&nbsp;Lexian Shi ,&nbsp;Menghui Zhao ,&nbsp;Hongwei Fang ,&nbsp;Xiangming Kong","doi":"10.1016/j.conbuildmat.2025.142141","DOIUrl":"10.1016/j.conbuildmat.2025.142141","url":null,"abstract":"<div><div>Carbonation curing of precast concrete components proposes a promising solution to increase the manufacturing efficiency and reduce the overall CO₂ emission of the concrete. In practical production, supplementary cementitious materials (SCMs) are frequently incorporated into precast concrete components. Despite this, the extent to which different SCMs modulate the carbonation curing process still remains unclear. This study employed quantitative methods to calculate the clinker consumption and product formation in various SCMs mortar systems under both steam and carbonation curing conditions, to elucidate the contribution of carbonation curing on different SCMs mortar systems. The results indicated that in comparison with steam curing, carbonation curing significantly enhanced the initial compressive and flexural strength of mortar, altered the timing and intensity of the primary hydration reactions, reduced the overall energy output during the early stages of cement hydration. The 7 h compressive strength of OPC was boosted by approximately 10–15 %, while the flexural strength increased by around 10–25 %. The XRD results showed that the CaCO₃ content in pastes containing FA, MS, GGBS, and CC was respectively 3.2 %, 5.2 %, 1.8 %, and 1.2 % higher than in steam curing, while this value in OPC was 3.7 %. TGA results revealed that the 10 % MS system exhibited the most significant increase in CaCO₃ content (∼7 %), when neglecting the contribution of amorphous calcium carbonate, which aligned with the quantitative results from XRD analysis. All these findings suggest that MS exhibited a synergistic effect with carbonation curing, significantly facilitated the initial strength of mortar.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"489 ","pages":"Article 142141"},"PeriodicalIF":7.4,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144271131","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of SO3 content in circulating fluidized bed fly ash on expansion performance of circulating fluidized bed ash-slag unfired brick","authors":"Wenbin Guo ,&nbsp;Mingkai Zhou ,&nbsp;Yuqiang Liu ,&nbsp;Lishun Chen ,&nbsp;Xiao Chen","doi":"10.1016/j.conbuildmat.2025.142239","DOIUrl":"10.1016/j.conbuildmat.2025.142239","url":null,"abstract":"<div><div>Circulating fluidized bed boiler fly ash and bottom slag (CFB ash-slag) have good pozzolanic activity and can be used to prepare unfired bricks. However, the high content of sulfur-fixing minerals in CFB ash-slag can cause volume expansion and cracking of unfired bricks. Therefore, in this paper, CFB fly ash is used as cementitious material, CFB bottom slag as sand and carbide slag as curing agent to prepare CFB ash-slag unfired brick. The influence of SO₃ content in CFB fly ash on the expansion and mechanical properties of the unfired brick is studied, and the dissolution rule of SO₄^2- of CFB fly ash was tested. The hydration products and microstructure of CFB ash-slag unfired brick were analyzed by microscopic methods such as XRD, TG-DTG, and SEM. The results show that with the increase of SO₃ content in CFB fly ash from 1.960 % to 10.677 %, the expansion rate of CFB ash-slag unfired bricks increased from 0.047 % to 1.074 %, the compressive strength increases first and then decreases at each immersion age. With the increase of immersion age, the compressive strength of unfired bricks increases when the SO₃ content of CFB fly ash is less than 4.878 %, and decreases first and then increases when the SO₃ content is more than 4.878 %. The microscopic test results show that with the increase of SO₃ content in CFB fly ash from 1.960 % to 10.677 %, the dissolution of SO₄^2- of CFB fly ash gradually increases, and the amount of ettringite generated by hydration increases from 16.01 % to 23.86 %, resulting in an increase in the expansion rate of CFB ash-slag unfired brick, and the compressive strength increases first and then decreases. In the late period of water immersion of CFB ash-slag unfired bricks (28d, 90d), the ettringite generated by hydration and other hydration products can further dense the pores caused by the expansion of the bricks in the early period of immersion, which increases the compressive strength of the unfired brick in the late period of immersion. Related studies have revealed the expansion law and mechanism of CFB ash-slag unfired brick, and provides a theoretical basis for its large-scale application.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"489 ","pages":"Article 142239"},"PeriodicalIF":7.4,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144271133","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}