Construction and Building Materials最新文献

{"title":"Mechanistic evaluation of biaxial and triaxial geogrids and geocells reinforcing C&D waste aggregate layers for sustainable flexible pavements","authors":"Vamsi Kommanamanchi ,&nbsp;Hariprasad Chennarapu ,&nbsp;Umashankar Balunaini","doi":"10.1016/j.conbuildmat.2025.143867","DOIUrl":"10.1016/j.conbuildmat.2025.143867","url":null,"abstract":"<div><div>Integrating geosynthetics with recycled aggregates in pavement construction presents a technically reliable and environmentally sustainable alternative to natural aggregates, aligning with circular economy principles. This study evaluates the structural performance of geosynthetic reinforced base layers constructed using 100 % recycled aggregate (RA), sourced from a construction and demolition (C&amp;D) waste processing facility, and compares the performance of base layers prepared with natural aggregate (NA). A series of static plate load tests were conducted on reinforced and unreinforced sections over subgrades with CBR values of 3 % and 9 %, incorporating biaxial geogrids, triaxial geogrids, and geocells at varying depths. For the tested configurations, geocell reinforcement with a 150 mm cell depth achieved the highest modulus improvement factor and layer coefficient ratio placed corresponding to optimal placement depth (u/a of 0.33). Similarly, triaxial geogrid (GRD1) exhibited superior performance at a placement depth of (u/a of 0.33) among geogrids, while biaxial geogrid (GRD2) exhibited moderate improvements for both the test conditions (i.e., base layers with recycled and natural aggregates). Furthermore, unreinforced and reinforced pavement layers with recycled aggregates achieved resilient moduli within the range of 261.6 MPa and 746.6 MPa, enabling significant impact on the pavement layers while maintaining critical strains within permissible limits. The findings provide novel insights into the comparative structural behaviour of pavement layers constructed using recycled and natural aggregate consisting of wet mix macadam (WMM). Additionally, the quantified improvement factors can conform to mechanistic empirical pavement design frameworks, supporting the development of sustainable and structurally efficient pavement systems.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"497 ","pages":"Article 143867"},"PeriodicalIF":8.0,"publicationDate":"2025-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145263776","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":"Mechanistic insights into the colloidal co-assembly of deeply degraded tire rubber and asphalt binder","authors":"Shanshan Wang ,&nbsp;Zhijun Li ,&nbsp;Shifeng Wang","doi":"10.1016/j.conbuildmat.2025.143935","DOIUrl":"10.1016/j.conbuildmat.2025.143935","url":null,"abstract":"<div><div>The co-colloidal architecture synthesized from deeply degraded tire rubber (DR) and asphalt binder confers exceptional stability to the composite system. While the colloidal organization of asphalt binder has been extensively characterized and scientifically validated, the mechanistic role of DR in modulating colloidal structural evolution remains a critical knowledge gap in interfacial material science. In this study, DR was separated into sol (DRS) and gel (DRG) phases, and their individual interfacial interactions with asphalt binder were investigated. Molecular dynamics simulations, contact angle measurements, thermogravimetric analysis, attenuated total reflectance Fourier transform infrared spectroscopy, Raman spectroscopy, and dynamic mechanical analyzer were employed to evaluate the physicochemical properties of DRS, DRG and different asphalts. Furthermore, the microstructure of the colloids was analyzed via atomic force microscopy (AFM) and optical microscopy (OM). The interactions between DRS and asphalt during compounding are attributed to their identical polarity and minimal solubility parameter differences (Δδ&lt;1 (J/cm³)^0.5). Strong interfacial adsorption and reactive bonding significantly altered the dispersion and interaction of DRG with asphalt binder. The performances of rubberized asphalt exhibited non-linear behavior beyond linear superposition of DRS modified asphalt and DRG modified asphalt characteristics, reflecting complex multiphase interactions between DR and asphalt colloids. Finally, based on AFM and OM observations, colloidal structures were proposed for the modified asphalts. These observations revealed the presence of characteristic bee-like structures in BA and DRSMA, but not in DRMA or DRGMA.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"497 ","pages":"Article 143935"},"PeriodicalIF":8.0,"publicationDate":"2025-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145264411","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":"Investigating the effect of antioxidants on aging behavior of asphalt binders: A chemo-rheological testing and characterization","authors":"Behnam Jahangiri ,&nbsp;Seyed Farhad Abdollahi ,&nbsp;Hamzeh Haghshenas ,&nbsp;Adrian Andriescu ,&nbsp;Aaron Leavitt ,&nbsp;David Mensching","doi":"10.1016/j.conbuildmat.2025.142693","DOIUrl":"10.1016/j.conbuildmat.2025.142693","url":null,"abstract":"<div><div>Antioxidants (AOs) are additives that can control asphalt oxidation and extend pavement service life. However, the final product may fail to provide the desired long-term performance and in-service aging mitigation without a comprehensive characterization of the AO and asphalt binder blends. This study employed rheological and chemical methods to characterize three AOs—butylated hydroxytoluene (BHT), zinc diethyldithiocarbamate (ZDEC), and ethylenediaminetetraacetic acid (EDTA)—incorporated at two dosage levels into two performance grade (PG) binders (PG 64–34 and PG 64–22). The obtained binder properties and indices at different aging levels, temperatures, and testing conditions were used to evaluate the effectiveness of these AOs in slowing the aging progression. The Glover-Rowe parameter showed that 4 % ZDEC could extend the aging time of the PG 64–34 binder in a pressure aging vessel from 60 h to 124 h before meeting the significant block cracking threshold. Additionally, 2 % ZDEC resulted in a one-grade change on the low temperature PG of the PG 64–22 binder, bumping down the resultant material to PG 64–28. On the other hand, <em>S</em>-value and <em>m</em>-value parameters from the bending beam rheometer test indicated that low-temperature cracking resistance could be reduced after BHT and EDTA modification. Data also showed that increasing EDTA dosage from 0.1 % to 2.0 % could diminish antiaging capability. These findings were supported by the carbonyl and sulfoxide indices obtained from Fourier-transform infrared spectroscopy. The AO modification efficacy of ZDEC was further validated using a third binder (PG 64–22) sourced from Virginia. Overall, BHT and EDTA were not nearly as favorable for use in asphalt binders as ZDEC.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"497 ","pages":"Article 142693"},"PeriodicalIF":8.0,"publicationDate":"2025-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145264538","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":"Impact of unbound aggregate packing on the dense bituminous mix properties: Experimental and discrete element model investigation","authors":"P.V. Arjun,&nbsp;Venkata Akhilesh Danam,&nbsp;Kusam Sudhakar Reddy,&nbsp;Arghya Deb","doi":"10.1016/j.conbuildmat.2025.143919","DOIUrl":"10.1016/j.conbuildmat.2025.143919","url":null,"abstract":"<div><div>The aggregate gradation and the resulting packing structure significantly affect the performance of the bituminous pavements. Available literature reveals the limitations of past studies such as limited range of aggregate gradations and nominal maximum aggregate sizes (NMAS) considered and the lack of validation of DEM results, emphasizing the need for comprehensive evaluation of aggregate packing characteristics and their effect on mix properties. In this study, the influence of the packing characteristics of dense aggregate gradations of different NMAS, evaluated experimentally and using discrete element modelling (DEM), on bituminous mix properties, was studied. The study considers geometrical packing indicators such as voids in coarse aggregate (VCA), coordination number (CN), and the coefficient of curvature (Cc) of gradation curve to evaluate the packing condition of unbound aggregate blends. VCA was measured experimentally to validate the DE models. The CN was evaluated for different gradations using DEM. Volumetric parameters of bituminous mixes, such as effective design binder content (P_b-eff.) and voids in mineral aggregate (VMA), and mechanical properties, such as indirect tensile strength (ITS), resilient modulus (M_r), and permanent deformation characteristics, were evaluated experimentally. The smaller the NAMS and the finer the gradation, the higher the values of VCA and CN. VCA and CN correlated well with VMA and P_b-eff.. CN and Cc explained rutting resistance, ITS, and M_r. Higher CN resulted in better interlocking and higher load-bearing capacity. Aggregate gradations with VCA &gt; 36.5 %, Cc &lt; 1.2, and CN &gt; 3.2 produced bituminous mixes exhibiting significantly higher ITS, M_r and rutting resistance.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"497 ","pages":"Article 143919"},"PeriodicalIF":8.0,"publicationDate":"2025-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145263778","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":"Microstructural and multiscale performance regulation of UHPC by plant ash-modified bamboo fibers: A green interfacial strategy","authors":"Jie Tang ,&nbsp;Tianwang Xiong ,&nbsp;Hua Zhao ,&nbsp;Chi Yao ,&nbsp;Xiaojian Gao","doi":"10.1016/j.conbuildmat.2025.143857","DOIUrl":"10.1016/j.conbuildmat.2025.143857","url":null,"abstract":"<div><div>In this study, the effects of NaOH and plant ash treatments on the surface properties of bamboo fibers and their interfacial performance in ultra-high-performance concrete (UHPC) were systematically investigated. Alkaline modification altered fiber morphology, chemistry, and wettability, thereby influencing workability, mechanical strength, and microstructure of UHPC. Excessive NaOH (10 %) caused surface erosion, functional group loss, and reduced mechanical performance. In contrast, plant ash at 10–20 % concentrations preserved fiber roughness, enhanced polar group exposure, improved hydrophobicity, and increased compressive (up to 132.37 MPa) and flexural (+29.7 %) strengths. Microstructural analysis confirmed that plant ash promoted stable Ca/Si-rich interfacial layers, balanced hydration products, and refined pore structures. SEM-EDS mapping revealed a continuous Si- and Ca-rich reaction zone with stable Ca/Si ratios (1.2–1.6) in the ash-treated groups. TG analysis indicated increased CH content (8.28 % for 20 % Ash) and stable bound water retention. FTIR spectra showed preservation of the main Si–O–Si peak at 1083 cm⁻¹ and an increased proportion of Q¹ structures, reflecting enhanced silicate polymerization. MIP results demonstrated reduced total porosity (20 % Ash group, 6.04 %) and a higher fine pore (&lt;50 nm) fraction (51.7 %), indicating improved compactness and homogeneity. These improvements are attributed to mild surface etching and in-situ mineral deposition, enhancing fiber–matrix bonding and hydration stability. Overall, plant ash treatment offers a green and effective interfacial engineering strategy for incorporating biomass fibers in high-performance cementitious composites.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"497 ","pages":"Article 143857"},"PeriodicalIF":8.0,"publicationDate":"2025-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145263783","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 and numerical characterization of cardboard–date palm fiber–polystyrene composites: Thermal assessment and techno-economic analysis","authors":"Youssef Khrissi,&nbsp;Abderrahim Benallel,&nbsp;Amine Tilioua","doi":"10.1016/j.conbuildmat.2025.143962","DOIUrl":"10.1016/j.conbuildmat.2025.143962","url":null,"abstract":"<div><div>Improving the energy efficiency of buildings and thermal comfort are significant challenges, both socially and in terms of regulations. Enhancing the thermal performance of building envelopes using bio-based recycled insulation materials is a relevant solution. However, there is currently a lack of standardised thermal and durability data for composites combining cardboard, date palm fibers, and polystyrene, which limits their acceptance in building applications. This study focuses on the thermal, mechanical, and hydric characterization of a new insulation material composed of recycled components, with the aim of its application in the building sector. The materials are composed of 80 % cardboard and 20 % fibers, with the addition of 2 %, 4 %, and 6 % polystyrene. Thermal performance was evaluated using two methods: the high-insulation house and the Hot Disk device, which allows for precise measurements. An experimental setup was used to simulate humid conditions and evaluate capillary absorption. Compression tests on cylindrical samples revealed good mechanical strength, particularly in radially oriented layers. The results show that the apparent density of the composites ranges from 213 to 264 kg·m⁻³ , thermal conductivity from 0.085 to 0.104 W·m⁻¹ ·K⁻¹ , water absorption from 217 % to 297 %, and compressive strength from 0.8 to 3.3 MPa. The optimal thickness is between 0.11 and 0.19 m, resulting in savings of between 60.70 $.m⁻² and 61.65 $.m⁻² on energy costs, with a return on investment of between 1.73 and 1.85 years. Although the composites achieve thermal conductivity values within the insulation range, their high susceptibility to moisture requires careful management at the design stage. Installation should therefore be limited to interior dry environments or protected façades, with the use of vapour control layers or ventilated rainscreens, and should avoid direct ground contact or exposure to driving rain without adequate protection. Overall, the study demonstrates that these recycled composites are cost-effective alternatives for improving building energy efficiency.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"497 ","pages":"Article 143962"},"PeriodicalIF":8.0,"publicationDate":"2025-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145263779","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":"Shear bond strength of patch repair using hybrid alkali-activated binders exposed to H2SO4 and MgSO4 solutions","authors":"Chattarika Phiangphimai ,&nbsp;Chirdsakul Lathulee ,&nbsp;Sakonwan Hanjitsuwan ,&nbsp;Khattiya Chompoovong ,&nbsp;Tanakorn Phoo-ngernkham ,&nbsp;Witawat Singsang ,&nbsp;Prinya Chindaprasirt","doi":"10.1016/j.conbuildmat.2025.143941","DOIUrl":"10.1016/j.conbuildmat.2025.143941","url":null,"abstract":"<div><div>This study evaluates the performance of hybrid alkali-activated binders (HAAB), synthesized from high-calcium fly ash (FA) and Portland cement (PC), as alternative patch repair materials for concrete structures exposed to chemically aggressive environments. HAAB mortars were formulated with different FA-to-PC proportions and varying sodium silicate-to-sodium hydroxide (SS/SH) ratios. Slant shear strength tests were performed on repaired specimens before and after immersion in 5 % magnesium sulfate (MgSO₄) and sulfuric acid (H₂SO₄) for 30, 60, and 90 days. Test results showed that HAAB mortars retained 15–25 % higher shear bond strength than commercial repair mortars (CRMs), with the difference being most pronounced under H₂SO₄ exposure. The best performance was achieved with 20 wt% PC replacement and an SS/SH ratio of 1.5, exhibiting bond strength exceeding 9 MPa after 90 days in H₂SO₄, compared to 6.8 MPa for CRM. Life-cycle analysis revealed a 22 % reduction in carbon emissions and a 19 % decrease in material costs for HAAB relative to CRMs. Therefore, these results highlight the promise of FA-PC-based HAAB mortars as sustainable, durable, and cost-effective alternatives for the repair and rehabilitation of concrete structures subjected to chemically aggressive environments.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"497 ","pages":"Article 143941"},"PeriodicalIF":8.0,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145264259","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":"Preparation of novel magnesia aggregates with large grain size and high thermal insulation using brine Mg(OH)2","authors":"Yibiao Xu ,&nbsp;Jiayi Ren ,&nbsp;Kequan Ding ,&nbsp;Yawei Li ,&nbsp;Yuanbing Li ,&nbsp;Wen Yan ,&nbsp;Qinghu Wang ,&nbsp;Xinjie Wang ,&nbsp;Liangsheng Ding ,&nbsp;Haoran Xu","doi":"10.1016/j.conbuildmat.2025.143916","DOIUrl":"10.1016/j.conbuildmat.2025.143916","url":null,"abstract":"<div><div>Magnesia, as major components of MgO-based refractories, has high refractoriness and excellent resistance to cement clinker and basic slag. To address the environmental and quality issues of traditional sintered magnesia fabricated by magnesite, novel sintered magnesia with low thermal conductivity, large grain size and enhanced properties was produced at 1400 °C in air from brine Mg(OH)₂ with incorporating Fe₂O₃ addition. The results showed that adding Fe₂O₃ caused MgO lattice distortion and formation of MgFe₂O₄ phase, leading to obvious MgO grain growth and reduction of apparent porosity. Due to lattice distortion and formation of low thermal conductivity intergranular MgFe₂O₄ networks, thermal insulation was enhanced apparently. The MgFe₂O₄ formation lowered thermal expansion coefficient and caused transgranular fracture and crack deflection, effectively improving the thermal shock resistance. Besides, slag corrosion resistance improved with increasing Fe₂O₃ to 12 wt% because of the reduced apparent porosity and enlarged MgO grain size, but then lowered with further increasing Fe₂O₃ amount due to presence of more unstable intergranular MgFe₂O₄. The specimen with 12 wt% Fe₂O₃ showed optimum comprehensive performance with an apparent porosity of 0.5 %, average MgO grain size of 17.5 μm, flexural strength of 127.9 MPa, and thermal conductivity of 10.8 W/(m·K) at 500 °C.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"497 ","pages":"Article 143916"},"PeriodicalIF":8.0,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145264342","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":"Unlocking the multi-mechanical properties of high-strength high-ductility engineered geopolymer composites incorporating waste glass powder as precursor","authors":"Zhiming Ma ,&nbsp;Jiayi Guo ,&nbsp;Shifeng Li ,&nbsp;Youchao Zhang ,&nbsp;Changqing Wang","doi":"10.1016/j.conbuildmat.2025.143920","DOIUrl":"10.1016/j.conbuildmat.2025.143920","url":null,"abstract":"<div><div>This study developed high-strength, high-ductility engineered geopolymer composites (EGC) using waste glass powder (WGP) as a green precursor, achieving high-value utilization of glass waste while expanding the low-carbon EGC system. WGP exhibited irregular particle morphology and contained abundant amorphous components, demonstrating both geopolymerization reactivity and filler effects. When WGP partially replaced moderate dosage of ground granulated blast-furnace slag (GGBS) and fly ash simultaneously, the resulting EGC developed a dense microstructure with enhanced micro-hardness, and elevating silicate modulus and alkali dosage further improved the micro-properties of WGP-EGC. The high-volume replacement of GGBS with WGP negatively impacted the EGC strength, while WGP substitution for fly ash exerted a positive effect. Combined replacement of both GGBS and fly ash with WGP produced WGP-EGC with comparable or better mechanical strengths than the reference EGC. Under a direct tensile loading, the uniaxial tensile performance initially improved and then declined as the WGP replacement ratio for either GGBS or fly ash increased, and the positive effect observed when WGP replaced fly ash was more significant than that when it replaced GGBS. When WGP replaced appropriate proportions of GGBS and fly ash simultaneously, the resulting WGP-EGC exhibited superior uniaxial tensile performance compared to the reference EGC. Increasing the silicate modulus and alkali dosage enhanced the WGP-EGC’s tensile stress and strain capacity, and concurrently increased the average crack width and number. The WGP-EGC prepared with 1.3 modulus and 9.0 % alkali dosage exhibited the best tensile performance, achieving a tensile stress of 12.9 MPa and a tensile strain of 8.5 %.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"497 ","pages":"Article 143920"},"PeriodicalIF":8.0,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145264258","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":"Utilization of carbonated recycled concrete powder in alkali-activated slag considering reaction duration effect","authors":"Hao Wang ,&nbsp;Liang Wang ,&nbsp;Ying Xu ,&nbsp;Qi Li ,&nbsp;Jian Zhou ,&nbsp;Rui Wu","doi":"10.1016/j.conbuildmat.2025.143917","DOIUrl":"10.1016/j.conbuildmat.2025.143917","url":null,"abstract":"<div><div>The aqueous carbonation of recycled concrete powder (RCP) is considered a promising approach to reduce carbon footprint in the environment and enhance RCP properties for use in new concrete. This work investigated the effects of RCP with different carbonation durations as a partial granulated blast furnace slag (GBFS) replacement on the setting and hardening properties of alkali-activated slag (AAS). In addition, the physical and chemical properties of RCP carbonated for different durations were characterized. Results showed that the carbonation degree of RCP increased with prolonging carbonation duration, reaching a maximum CO₂ uptake of 13.2 % after 20 min of carbonation. The submicron grade calcite particles and silica gel were identified as the dominant carbonated products. They promoted the C-(A)-S-H developed and refined the pore structure of blended mortars by filling effect and activity effect. As a result, the compressive strength of blended mortars with carbonated RCP achieved 7.3–22.3 % increments at 28d, compared to the blended mortar with pristine RCP. Moreover, the rapidly setting issue of AAS mortar could be alleviated by carbonated RCP with a long reaction duration. These findings provide a sustainable and effective solution for value-added application of RCP in the construction industry.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"497 ","pages":"Article 143917"},"PeriodicalIF":8.0,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145264412","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}