{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,7]],"date-time":"2026-05-07T10:19:45Z","timestamp":1778149185682,"version":"3.51.4"},"reference-count":102,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2025,9,27]],"date-time":"2025-09-27T00:00:00Z","timestamp":1758931200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004569","name":"Ministry of Science and Higher Education","doi-asserted-by":"publisher","award":["DWD\/6\/0528\/2022"],"award-info":[{"award-number":["DWD\/6\/0528\/2022"]}],"id":[{"id":"10.13039\/501100004569","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.mdpi.com"],"crossmark-restriction":true},"short-container-title":["Materials"],"abstract":"<jats:p>Fiber-reinforced foamed composites have recently attracted growing interest due to their potential in sustainable construction and advanced additive manufacturing. However, their performance strongly depends on the type of matrix and fiber system used. The aim of this study was to perform a comparative analysis of matrix type and fiber composition on the porosity, thermal behavior, and mechanical performance of 3D-printed fiber-reinforced foamed composites. To this end, cementitious mixtures (M1\u2013M3) were compared with alkali-activated hybrid binder systems (M4\u2013M6). The results revealed marked differences in mechanical strength, dimensional stability, moisture transport, and interlayer cohesion. Alkali-activated specimens, particularly M5 and M6, exhibited superior compressive, flexural, and shear strength; reduced water penetration; and improved fiber\u2013matrix bonding, associated with a denser and more homogeneous pore structure. In contrast, cementitious composites showed greater dimensional stability and easier process control, indicating practical advantages for large-scale on-site applications. The results highlight that while alkali activation and hybrid fiber reinforcement enhance structural performance, non-activated foamed concretes remain promising for applications prioritizing simplicity, reproducibility, and thermal insulation.<\/jats:p>","DOI":"10.3390\/ma18194498","type":"journal-article","created":{"date-parts":[[2025,9,29]],"date-time":"2025-09-29T12:59:46Z","timestamp":1759150786000},"page":"4498","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Comparison of Porosity and Thermal Conductivity of Concrete and Alkali-Activated Hybrid Binders in 3D-Printed Fiber-Reinforced Foamed Composites"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-9444-5699","authenticated-orcid":false,"given":"Magdalena","family":"Rudziewicz","sequence":"first","affiliation":[{"name":"Faculty of Materials Engineering and Physics, Cracow University of Technology, Warszawska 24, 31-155 Krak\u00f3w, Poland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6554-4613","authenticated-orcid":false,"given":"Marcin","family":"Maroszek","sequence":"additional","affiliation":[{"name":"Faculty of Materials Engineering and Physics, Cracow University of Technology, Warszawska 24, 31-155 Krak\u00f3w, Poland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8583-9459","authenticated-orcid":false,"given":"Marek","family":"Hebda","sequence":"additional","affiliation":[{"name":"Faculty of Materials Engineering and Physics, Cracow University of Technology, Warszawska 24, 31-155 Krak\u00f3w, Poland"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,27]]},"reference":[{"key":"ref_1","unstructured":"Council of the European Union (2025, August 18). European Green Deal. Consilium (Council of the European Union). Available online: https:\/\/www.consilium.europa.eu\/en\/policies\/european-green-deal\/."},{"key":"ref_2","unstructured":"United Nations (2025, August 18). The 17 Goals; United Nations Sustainable Development Platform (USA, September 2015). Available online: https:\/\/sdgs.un.org\/goals."},{"key":"ref_3","unstructured":"European Commission (2020). Communication from the Commission to the European Parliament, the Council, the European Economic and Social Committee and the Committee of the Regions: A New Circular Economy Action Plan for a Cleaner and More Competitive Europe, COM\/2020\/98 Final, European Commission. Available online: https:\/\/eur-lex.europa.eu\/legal-content\/EN\/TXT\/?uri=COM:2020:98:FIN."},{"key":"ref_4","unstructured":"Hillsdon, M. (2025, August 18). Heavy Lift Required to Solve Cement\u2019s Carbon Conundrum. Reuters (Ethical Corporation Magazine), 24 June 2024. Available online: https:\/\/www.reuters.com\/sustainability\/decarbonizing-industries\/heavy-lift-required-solve-cements-carbon-conundrum-2024-06-24\/."},{"key":"ref_5","first-page":"e00443","article-title":"The Influence of Some Calcined Clays from Nigeria as Clinker Substitute in Cementitious Systems","volume":"13","author":"Akindahunsi","year":"2020","journal-title":"Case Stud. Constr. Mater."},{"key":"ref_6","first-page":"256","article-title":"Impact of Supplementary Cementitious Materials (SCMs) on Physical\u2013Mechanical Properties and Microstructure of Styrene Polyacrylic (SPA) Polymer Modified Mortars","volume":"24","author":"Berkak","year":"2025","journal-title":"Rev. Constr."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"100123","DOI":"10.1016\/j.clema.2022.100123","article-title":"The Role of Supplementary Cementitious Materials in Hydration, Durability and Shrinkage of Cement-Based Materials, Their Environmental and Economic Benefits: A Review","volume":"5","author":"Ndahirwa","year":"2022","journal-title":"Clean. Mater."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"136141","DOI":"10.1016\/j.conbuildmat.2024.136141","article-title":"History, Recent Progress, and Future Challenges of Alkali-Activated Binders\u2014An Overview","volume":"426","author":"Nasir","year":"2024","journal-title":"Constr. Build. Mater."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Razak, R., Vizureanu, P., Abdullah, M.M.A.B., Mohamed, R., and Chuan Hao, D. (2024). Durability Testing Protocols for Concrete Made with Alternative Binders and Recycled Materials. Mining and Metallurgical Wastes Based Alkali-Activated Materials, Springer.","DOI":"10.1007\/978-981-97-6285-9_6"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"110823","DOI":"10.1016\/j.jobe.2024.110823","article-title":"Towards Sustainable Artificial Aggregate Production Using Industrial Waste and CO2: A Comprehensive Review","volume":"97","author":"Xu","year":"2024","journal-title":"J. Build. Eng."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"109152","DOI":"10.1016\/j.istruc.2025.109152","article-title":"A Comprehensive Study on the Valorization of Recycled Concrete Aggregates in 3D-Printable Cementitious Systems","volume":"77","year":"2025","journal-title":"Structures"},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Ricciotti, L., Apicella, A., Perrotta, V., and Aversa, R. (2023). Geopolymer Materials for Extrusion-Based 3D-Printing: A Review. Polymers, 15.","DOI":"10.3390\/polym15244688"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"112841","DOI":"10.1016\/j.jobe.2025.112841","article-title":"A Comparative Study on the Effectiveness of Fly Ash and Blast Furnace Slag as Partial Cement Substitution in 3D Printable Concrete","volume":"108","author":"Kaya","year":"2025","journal-title":"J. Build. Eng."},{"key":"ref_14","unstructured":"Hoenig, V., Schall, A., Sultanov, N., Papkalla, S., and Ruppert, J. (2022). Status and Prospects of Alternative Raw Materials in the European Cement Sector, European Cement Research Academy. Available online: https:\/\/cembureau.eu\/media\/ez5mwmpq\/220502-ecra-alternative-raw-materials-study.pdf."},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Liu, Z., Takasu, K., Suyama, H., Koyamada, H., Liu, S., and Hao, Q. (2022). The Effect of Cementitious Materials on the Engineering Properties and Pore Structure of Concrete with Recycled Fine Aggregate. Materials, 16.","DOI":"10.3390\/ma16010305"},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Suarez-Riera, D., Restuccia, L., Falliano, D., Ferro, G.A., Tuliani, J.-M., Pavese, M., and Lavagna, L. (2024). An Overview of Methods to Enhance the Environmental Performance of Cement-Based Materials. Infrastructures, 9.","DOI":"10.3390\/infrastructures9060094"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"100284","DOI":"10.1016\/j.dibe.2023.100284","article-title":"Advancements in Low-Carbon Concrete as a Construction Material for the Sustainable Built Environment","volume":"16","author":"Althoey","year":"2023","journal-title":"Dev. Built Environ."},{"key":"ref_18","unstructured":"European Environment Agency (2023). Accelerating the Energy Efficiency Renovation of Residential Buildings\u2014A Behavioural Approach, EEA. Available online: https:\/\/www.eea.europa.eu\/publications\/accelerating-the-energy-efficiency."},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Cecconi, M., Cumo, F., Pennacchia, E., Romeo, C., and Zylka, C. (2025). BEST\u2014Building Energy-Saving Tool for Sustainable Residential Buildings. Appl. Sci., 15.","DOI":"10.3390\/app15126817"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1411","DOI":"10.3390\/encyclopedia4040092","article-title":"Energy Efficiency in Buildings: Performance Gaps and Sustainable Materials","volume":"4","author":"Igugu","year":"2024","journal-title":"Encyclopedia"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"044004","DOI":"10.1088\/1748-9326\/ab0fe3","article-title":"Material Efficiency Strategies to Reducing Greenhouse Gas Emissions Associated with Buildings, Vehicles, and Electronics\u2014A Review","volume":"14","author":"Hertwich","year":"2019","journal-title":"Environ. Res. Lett."},{"key":"ref_22","unstructured":"European Environment Agency (2022). Building Renovation: Where Circular Economy and Climate Meet, EEA. Available online: https:\/\/www.eea.europa.eu\/publications\/building-renovation-where-circular-economy."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"133808","DOI":"10.1016\/j.conbuildmat.2023.133808","article-title":"Selection of Eco-Friendly Alternative Brick for Sustainable Development: A Study on Technical, Economic, Environmental and Social Feasibility","volume":"408","author":"Maaze","year":"2023","journal-title":"Constr. Build. Mater."},{"key":"ref_24","first-page":"e03365","article-title":"The Effect of Lightweight Geopolymer Concrete Containing Air Agent on Building Envelope Performance and Internal Thermal Comfort","volume":"20","author":"Mostafa","year":"2024","journal-title":"Case Stud. Constr. Mater."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"100177","DOI":"10.1016\/j.dibe.2023.100177","article-title":"Smart Materials and Technologies for Sustainable Concrete Construction","volume":"15","author":"Nilimaa","year":"2023","journal-title":"Dev. Built Environ."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"120157","DOI":"10.1016\/j.engstruct.2025.120157","article-title":"Axial Compression Behavior of GFRP-Steel Composite Tube Confined Seawater Sea-Sand Concrete Intermediate Long Columns","volume":"333","author":"Fu","year":"2025","journal-title":"Eng. Struct."},{"key":"ref_27","first-page":"e04024","article-title":"Sustainable Fabrication of Lightweight Geopolymer Foams from Silica-Fume and Zeolite Tuffs: Utilizing Al as Foaming Agent for Thermal Insulation","volume":"21","author":"Ibrahim","year":"2024","journal-title":"Case Stud. Constr. Mater."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"\u0141ach, M. (2021). Geopolymer Foams\u2014Will They Ever Become a Viable Alternative to Popular Insulation Materials?\u2014A Critical Opinion. Materials, 14.","DOI":"10.3390\/ma14133568"},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Ziejewska, C., Marczyk, J., Korniejenko, K., Bednarz, S., Sroczyk, P., \u0141ach, M., Miku\u0142a, J., Figiela, B., Szechy\u0144ska-Hebda, M., and Hebda, M. (2022). 3D Printing of Concrete-Geopolymer Hybrids. Materials, 15.","DOI":"10.3390\/ma15082819"},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Korniejenko, K., P\u0142awecka, K., and Kozub, B. (2022). An overview for modern energy-efficient solutions for lunar and martian habitats made based on geopolymers composites and 3D printing technology. Energies, 15.","DOI":"10.3390\/en15249322"},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Barve, P., Bahrami, A., and Shah, S. (2023). Geopolymer 3D Printing: A Comprehensive Review on Rheological and Structural Performance Assessment, Printing Process Parameters, and Microstructure. Front. Mater., 10.","DOI":"10.3389\/fmats.2023.1241869"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"132869","DOI":"10.1016\/j.conbuildmat.2023.132869","article-title":"A Review of 3D Printing of Geopolymer Composites for Structural and Functional Applications","volume":"400","author":"Shilar","year":"2023","journal-title":"Constr. Build. Mater."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"103273","DOI":"10.1016\/j.jobe.2021.103273","article-title":"Stabilized Homogeneous Porous Structure and Pore Type Effects on the Properties of Lightweight Kaolinite-Based Geopolymers","volume":"44","author":"Sornlar","year":"2021","journal-title":"J. Build. Eng."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"106629","DOI":"10.1016\/j.compositesa.2021.106629","article-title":"Porous Geopolymer Composites: A Review","volume":"150","author":"Zhang","year":"2021","journal-title":"Compos. Part A Appl. Sci. Manuf."},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Bazan, P., Figiela, B., Kozub, B., \u0141ach, M., Mr\u00f3z, K., Melnychuk, M., and Korniejenko, K. (2024). Geopolymer Foam with Low Thermal Conductivity Based on Industrial Waste. Materials, 17.","DOI":"10.3390\/ma17246143"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"97","DOI":"10.1016\/j.cemconcomp.2015.03.013","article-title":"Mechanical, Thermal Insulation, Thermal Resistance and Acoustic Absorption Properties of Geopolymer Foam Concrete","volume":"62","author":"Zhang","year":"2015","journal-title":"Cem. Concr. Compos."},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Pra\u0142at, K., Ciemnicka, J., Koper, A., Buczkowska, K.E., and \u0141o\u015b, P. (2021). Comparison of the Thermal Properties of Geopolymer and Modified Gypsum. Polymers, 13.","DOI":"10.3390\/polym13081220"},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Castillo, H., Collado, H., Droguett, T., S\u00e1nchez, S., Vesely, M., Garrido, P., and Palma, S. (2021). Factors Affecting the Compressive Strength of Geopolymers: A Review. Minerals, 11.","DOI":"10.3390\/min11121317"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"131830","DOI":"10.1016\/j.conbuildmat.2023.131830","article-title":"Foaming Processes and Properties of Geopolymer Foam Concrete: Effect of the Activator","volume":"391","author":"Liu","year":"2023","journal-title":"Constr. Build. Mater."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"127083","DOI":"10.1016\/j.conbuildmat.2022.127083","article-title":"Synthesis of Industrial Solid Wastes-Based Geopolymer Foams for Building Energy Conservation: Effects of Metallic Aluminium and Reclaimed Materials","volume":"328","author":"Shen","year":"2022","journal-title":"Constr. Build. Mater."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"4","DOI":"10.1007\/s44416-025-00003-x","article-title":"Geopolymer foam concrete: A review of pore characteristics, compressive strength and artificial intelligence in GFC strength simulations","volume":"1","author":"Abdellatief","year":"2025","journal-title":"Discov. Concr. Cem."},{"key":"ref_42","doi-asserted-by":"crossref","unstructured":"Siyal, A.A., Mohamed, R.M.S.R., Musa, S., Rassem, H.H., and Khamidun, M.H. (2024). A Review of the Performance of Geopolymer Catalysts for Biodiesel Production. Biomass Bioenergy, 190.","DOI":"10.1016\/j.biombioe.2024.107373"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"327","DOI":"10.1016\/j.jenvman.2018.07.046","article-title":"A Review on Geopolymers as Emerging Materials for the Adsorption of Heavy Metals and Dyes","volume":"224","author":"Siyal","year":"2018","journal-title":"J. Environ. Manag."},{"key":"ref_44","doi-asserted-by":"crossref","unstructured":"Kud\u0142acik-Kramarczyk, S., Drabczyk, A., Figiela, B., and Korniejenko, K. (2023). Geopolymers: Advanced Materials in Medicine, Energy, Anticorrosion and Environmental Protection. Materials, 16.","DOI":"10.3390\/ma16237416"},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"127187","DOI":"10.1016\/j.conbuildmat.2022.127187","article-title":"A State-of-the-Art Review on Fibre-Reinforced Geopolymer Composites","volume":"330","author":"Aziz","year":"2022","journal-title":"Constr. Build. Mater."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"133109","DOI":"10.1016\/j.conbuildmat.2023.133109","article-title":"Mechanical Properties, Flexural Behaviour, and Ductility Characteristics of Fibre-Reinforced Geopolymer Mortar","volume":"403","author":"Gaddafi","year":"2023","journal-title":"Constr. Build. Mater."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"119697","DOI":"10.1016\/j.conbuildmat.2020.119697","article-title":"Optimization of a Reinforced Geopolymer Composite Using Natural Fibers and Construction Wastes","volume":"258","author":"Kim","year":"2020","journal-title":"Constr. Build. Mater."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"100065","DOI":"10.1016\/j.oceram.2021.100065","article-title":"Factors Influencing Thermal Conductivity and Compressive Strength of Natural Fiber-Reinforced Geopolymer Foams","volume":"5","author":"Drewler","year":"2021","journal-title":"Open Ceram."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"e35947","DOI":"10.1016\/j.heliyon.2024.e35947","article-title":"Design and Characterization of Geopolymer Foams Reinforced with Miscanthus \u00d7 giganteus Fibres","volume":"10","author":"Witzleben","year":"2024","journal-title":"Heliyon"},{"key":"ref_50","doi-asserted-by":"crossref","unstructured":"Agustini, N.K.A., Triwiyono, A., Sulistyo, D., and Suyitno, S. (2021). Mechanical Properties and Thermal Conductivity of Fly Ash-Based Geopolymer Foams with Polypropylene Fibers. Appl. Sci., 11.","DOI":"10.3390\/app11114886"},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"218","DOI":"10.1016\/j.compositesb.2015.02.023","article-title":"The Effect of Organic and Inorganic Fibres on the Mechanical and Thermal Properties of Aluminate Activated Geopolymers","volume":"76","author":"Masi","year":"2015","journal-title":"Compos. Part B Eng."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"231","DOI":"10.46604\/ijeti.2024.13346","article-title":"Leveraging 3D Printing Capability for Geopolymer Composites Based on Fly Ash with Cotton Fibers Addition","volume":"14","author":"Kozub","year":"2024","journal-title":"Int. J. Eng. Technol. Innov."},{"key":"ref_53","doi-asserted-by":"crossref","unstructured":"\u0141a\u017aniewska-Piekarczyk, B., and Smyczek, D. (2024). The effect of mineral wool fiber additive on several mechanical properties and thermal conductivity in geopolymer binder. Materials, 17.","DOI":"10.3390\/ma17020483"},{"key":"ref_54","doi-asserted-by":"crossref","unstructured":"Kozub, B., Bazan, P., Gailitis, R., Korniejenko, K., and Mierzwi\u0144ski, D. (2021). Foamed Geopolymer Composites with the Addition of Glass Wool Waste. Materials, 14.","DOI":"10.3390\/ma14174978"},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"8545","DOI":"10.1007\/s13369-019-04074-4","article-title":"Investigation on Mode I Fracture Behavior of Hybrid Fiber-Reinforced Geopolymer Composites","volume":"44","author":"Asrani","year":"2019","journal-title":"Arab. J. Sci. Eng."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"567","DOI":"10.1680\/jadcr.23.00205","article-title":"Three-Dimensional Concrete Printing Technology from a Rheology Perspective: A Review","volume":"36","author":"Yang","year":"2024","journal-title":"Adv. Cem. Res."},{"key":"ref_57","doi-asserted-by":"crossref","unstructured":"Baziak, A., P\u0142awecka, K., Hager, I., Castel, A., and Korniejenko, K. (2021). Development and Characterization of Lightweight Geopolymer Composite Reinforced with Hybrid Carbon and Steel Fibers. Materials, 14.","DOI":"10.3390\/ma14195741"},{"key":"ref_58","doi-asserted-by":"crossref","unstructured":"Rudziewicz, M., Hutyra, A., Maroszek, M., Korniejenko, K., and Hebda, M. (2025). 3D-Printed Lightweight Foamed Concrete with Dispersed Reinforcement. Appl. Sci., 15.","DOI":"10.3390\/app15084527"},{"key":"ref_59","doi-asserted-by":"crossref","unstructured":"Rudziewicz, M., Maroszek, M., Setlak, K., G\u00f3ra, M., and Hebda, M. (2024). Optimization of Foams\u2014Polypropylene Fiber-Reinforced ConcreteMixtures Dedicated for 3D Printing. Materials, 17.","DOI":"10.3390\/ma17164106"},{"key":"ref_60","first-page":"277","article-title":"Wp\u0142yw sk\u0142adu mieszanki i wyj\u015bciowego zawilgocenia kruszywa lekkiego na sorpcyjno\u015b\u0107 kapilarn\u0105 betonu keramzytowego","volume":"64","author":"Narodowska","year":"2017","journal-title":"Czas. In\u017cynierii L\u0105dowej Sr. Archit."},{"key":"ref_61","unstructured":"Garbali\u0144ska, H., Walkowiak, M., and Wygocka, A. (2025, September 13). Ocena Wp\u0142ywu Rodzaju Cementu na Proces Podci\u0105gania Kapilarnego Wody w Zaprawach Modyfikowanych W\u0142\u00f3knami Polipropylenowymi. [Assessment of Influence of Cement Type on the Water Capillary Pull-Up Process in Mortars Modified with Polypropylene Fibres]. Available online: https:\/\/www.dnibetonu.com\/wp-content\/pdfs\/2006\/garbalinska_walkowiak_wygocka.pdf."},{"key":"ref_62","unstructured":"(2002). Methods of Test for Mortar for Masonry\u2014Part 18: Determination of Water Absorption Coefficient Due to Capillary Action of Hardened Mortar (Standard No. EN 1015-18:2002)."},{"key":"ref_63","doi-asserted-by":"crossref","unstructured":"Hager, I., Maroszek, M., Mr\u00f3z, K., K\u0119sek, R., Hebda, M., Dvorkin, L., and Marchuk, V. (2022). Interlayer Bond Strength Testing in 3D-Printed Mineral Materials for Construction Applications. Materials, 15.","DOI":"10.3390\/ma15124112"},{"key":"ref_64","doi-asserted-by":"crossref","unstructured":"Liu, X., Liu, E., and Fu, Y. (2023). Reduction in Drying Shrinkage and Efflorescence of Recycled Brick and Concrete Fine Powder\u2013Slag-Based Geopolymer. Appl. Sci., 13.","DOI":"10.3390\/app13052997"},{"key":"ref_65","doi-asserted-by":"crossref","first-page":"107244","DOI":"10.1016\/j.cemconres.2023.107244","article-title":"Autogenous Shrinkage of Alkali-Activated Slag: A Critical Review","volume":"172","author":"Li","year":"2023","journal-title":"Cem. Concr. Res."},{"key":"ref_66","doi-asserted-by":"crossref","unstructured":"Wang, H., Zheng, Y., and Yu, Z. (2024). Influence of Ambient Relative Humidity on the Shrinkage Strain of Engineered Geopolymer Composites Based on Orthogonal Experimental Design. Materials, 17.","DOI":"10.3390\/ma17174321"},{"key":"ref_67","doi-asserted-by":"crossref","first-page":"105304","DOI":"10.1016\/j.cemconcomp.2023.105304","article-title":"3D printing of an iron-rich slag based hybrid mortar: A durable, sustainable and cost-competitive product?","volume":"144","author":"Beersaerts","year":"2023","journal-title":"Cem. Concr. Compos."},{"key":"ref_68","doi-asserted-by":"crossref","first-page":"121372","DOI":"10.1016\/j.conbuildmat.2020.121372","article-title":"Effect of Shrinkage Reducing Admixture on Drying Shrinkage and Durability of Alkali-Activated Coal Gangue-Slag Material","volume":"270","author":"Ma","year":"2021","journal-title":"Constr. Build. Mater."},{"key":"ref_69","doi-asserted-by":"crossref","first-page":"127","DOI":"10.1007\/s41062-021-00496-y","article-title":"Effect of limestone powder on mechanical strength, durability and drying shrinkage of alkali-activated slag pastes","volume":"6","author":"Rashad","year":"2021","journal-title":"Innov. Infrastruct. Solut."},{"key":"ref_70","doi-asserted-by":"crossref","first-page":"125993","DOI":"10.1016\/j.conbuildmat.2021.125993","article-title":"Shrinkage mechanisms and shrinkage-mitigating strategies of alkali-activated slag composites: A critical review","volume":"318","author":"Zhang","year":"2022","journal-title":"Constr. Build. Mater."},{"key":"ref_71","doi-asserted-by":"crossref","unstructured":"Nedeljkovi\u0107, M., Li, Z., and Ye, G. (2018). Setting, Strength, and Autogenous Shrinkage of Alkali-Activated Fly Ash and Slag Pastes: Effect of Slag Content. Materials, 11.","DOI":"10.3390\/ma11112121"},{"key":"ref_72","first-page":"e03493","article-title":"Investigation of Shrinkage Mechanism of Alkali-Activated Slag","volume":"21","author":"Wei","year":"2024","journal-title":"Case Stud. Constr. Mater."},{"key":"ref_73","doi-asserted-by":"crossref","first-page":"101216","DOI":"10.1016\/j.jobe.2020.101216","article-title":"Utilization of Sheep Wool as Potential Fibrous Material in the Production of Concrete Composites","volume":"30","author":"Alyousef","year":"2020","journal-title":"J. Build. Eng."},{"key":"ref_74","doi-asserted-by":"crossref","first-page":"142938","DOI":"10.1016\/j.conbuildmat.2025.142938","article-title":"Strategic Control of Pore Structure in Ultra-High Performance Concrete via Tailored Rheological Property Modulation","volume":"492","author":"Li","year":"2025","journal-title":"Constr. Build. Mater."},{"key":"ref_75","doi-asserted-by":"crossref","first-page":"45","DOI":"10.1617\/s11527-021-01632-x","article-title":"Hardened properties and durability of large-scale 3D printed cement-based materials","volume":"54","author":"Zhang","year":"2021","journal-title":"Mater. Struct."},{"key":"ref_76","doi-asserted-by":"crossref","first-page":"132","DOI":"10.1016\/j.cemconres.2019.02.017","article-title":"Hardened Properties of 3D Printed Concrete: The Influence of Process Parameters on Interlayer Adhesion","volume":"119","author":"Wolfs","year":"2019","journal-title":"Cem. Concr. Res."},{"key":"ref_77","doi-asserted-by":"crossref","unstructured":"Lee, Y.J., Lee, S.-H., Kim, J.H., Jeong, H., Han, S.-J., and Kim, K.S. (2024). Interlayer Bond Strength of 3D Printed Concrete Members with Ultra High Performance Concrete (UHPC) Mix. Buildings, 14.","DOI":"10.3390\/buildings14072060"},{"key":"ref_78","doi-asserted-by":"crossref","first-page":"020012","DOI":"10.1063\/5.0007787","article-title":"Comparison of the Long-Term Properties of Foamed Concrete and Geopolymer Concrete in Compression","volume":"2239","author":"Gailitis","year":"2020","journal-title":"AIP Conf. Proc."},{"key":"ref_79","doi-asserted-by":"crossref","first-page":"012006","DOI":"10.1088\/1755-1315\/297\/1\/012006","article-title":"Mineral Wool Waste-Based Geopolymers","volume":"297","author":"Yliniemi","year":"2019","journal-title":"IOP Conf. Ser. Earth Environ. Sci."},{"key":"ref_80","doi-asserted-by":"crossref","unstructured":"Daza-Badilla, L., G\u00f3mez, R., D\u00edaz-Noriega, R., Avudaiappan, S., Skrzypkowski, K., Saavedra-Flores, E.I., and Korzeniowski, W. (2024). Thermal Conductivity in Concrete Samples with Natural and Synthetic Fibers. Materials, 17.","DOI":"10.3390\/ma17040817"},{"key":"ref_81","doi-asserted-by":"crossref","first-page":"107452","DOI":"10.1016\/j.clay.2024.107452","article-title":"Mechanical and thermal properties of geopolymers derived from metakaolin with iron mine waste","volume":"258","author":"Santos","year":"2024","journal-title":"Appl. Clay Sci."},{"key":"ref_82","doi-asserted-by":"crossref","unstructured":"Parcesepe, E., De Masi, R.F., Lima, C., Mauro, G.M., Maddaloni, G., and Pecce, M.R. (2021). Experimental Evaluation of the Mechanical Strengths and the Thermal Conductivity of GGBFS and Silica Fume Based Alkali-Activated Concrete. Materials, 14.","DOI":"10.3390\/ma14247717"},{"key":"ref_83","doi-asserted-by":"crossref","unstructured":"Przybek, A., Roma\u0144ska, P., Korniejenko, K., Krajniak, K., Hebdowska-Krupa, M., and \u0141ach, M. (2025). Thermal Properties of Geopolymer Concretes with Lightweight Aggregates. Materials, 18.","DOI":"10.3390\/ma18133150"},{"key":"ref_84","doi-asserted-by":"crossref","first-page":"121436","DOI":"10.1016\/j.conbuildmat.2020.121436","article-title":"Sorptivity and mechanical properties of fiber-reinforced concrete made with seawater and dredged sea-sand","volume":"270","author":"Vafaei","year":"2020","journal-title":"Constr. Build. Mater."},{"key":"ref_85","doi-asserted-by":"crossref","unstructured":"Rudziewicz, M., Maroszek, M., Hutyra, A., G\u00f3ra, M., Rusin-\u017burek, K., and Hebda, M. (2025). Influence of Foaming Agents and Stabilizers on Porosity in 3D Printed Foamed Concrete. Processes, 13.","DOI":"10.3390\/pr13020403"},{"key":"ref_86","doi-asserted-by":"crossref","first-page":"012092","DOI":"10.1088\/1757-899X\/551\/1\/012092","article-title":"Performance of Geopolymer Concrete When Exposed to Marine Environment","volume":"551","author":"Ahmad","year":"2019","journal-title":"IOP Conf. Ser. Mater. Sci. Eng."},{"key":"ref_87","doi-asserted-by":"crossref","first-page":"3592","DOI":"10.1166\/asl.2013.5187","article-title":"Comparison of Geopolymer Fly Ash and Ordinary Portland Cement to the Strength of Concrete","volume":"19","author":"Abdullah","year":"2013","journal-title":"Adv. Sci. Lett."},{"key":"ref_88","doi-asserted-by":"crossref","unstructured":"R\u016f\u017eek, V., Louda, P., Buczkowska, K., Just, P., Pra\u0142at, K., Ciemnicka, J., and Plaskota, P. (2022). Modifying Geopolymer Wettability by Plasma Treatment and High-Carbon Fly Ash. Front. Built Environ., 8.","DOI":"10.3389\/fbuil.2022.991496"},{"key":"ref_89","doi-asserted-by":"crossref","unstructured":"Udhaya Kumar, T., Vinod Kumar, M., Salunkhe, S., and Cep, R. (2024). Evaluation of non-destructive testing and long-term durability of geopolymer aggregate concrete. Front. Built Environ., 10.","DOI":"10.3389\/fbuil.2024.1454687"},{"key":"ref_90","doi-asserted-by":"crossref","unstructured":"Hao, E., Li, Y., Zhang, D., Zhu, W., Liu, R., Wang, X., Cao, Y., Gu, Y., and Zheng, X. (2025). Research on the mechanism of pore structure on water transportation in cement-based materials. PLoS ONE, 20.","DOI":"10.1371\/journal.pone.0327659"},{"key":"ref_91","first-page":"648","article-title":"Interlayer Bond Strength of 3D Printing Cement Paste by Cross-Bonded Method","volume":"47","author":"Liu","year":"2019","journal-title":"J. Chin. Ceram. Soc."},{"key":"ref_92","doi-asserted-by":"crossref","unstructured":"Babafemi, A.J., Kolawole, J.T., Miah, M.J., Paul, S.C., and Panda, B. (2021). A Concise Review on Interlayer Bond Strength in 3D Concrete Printing. Sustainability, 13.","DOI":"10.3390\/su13137137"},{"key":"ref_93","doi-asserted-by":"crossref","first-page":"586","DOI":"10.1016\/j.conbuildmat.2019.01.235","article-title":"Effects of layer-interface properties on mechanical performance of concrete elements produced by extrusion-based 3D-printing","volume":"205","author":"Nerella","year":"2019","journal-title":"Constr. Build. Mater."},{"key":"ref_94","doi-asserted-by":"crossref","unstructured":"Lv, C., Shen, H., Liu, J., Wu, D., Qu, E., and Liu, S. (2022). Properties of 3D Printing Fiber-Reinforced Geopolymers Based on Interlayer Bonding and Anisotropy. Materials, 15.","DOI":"10.3390\/ma15228032"},{"key":"ref_95","doi-asserted-by":"crossref","first-page":"105805","DOI":"10.1016\/j.cemconcomp.2024.105805","article-title":"Interlayer Bonding Performance of 3D Printed Engineered Cementitious Composites (ECC): Rheological Regulation and Fiber Hybridization","volume":"154","author":"Ding","year":"2024","journal-title":"Cem. Concr. Compos."},{"key":"ref_96","doi-asserted-by":"crossref","first-page":"113295","DOI":"10.1016\/j.mtcomm.2025.113295","article-title":"Modulation of Initial CaO\/Al2O3 and SiO2\/Al2O3 Ratios on the Properties of Slag\/Fly Ash-Based Geopolymer Stabilized Clay: Synergistic Effects and Stabilization Mechanism","volume":"47","author":"Luo","year":"2025","journal-title":"Mater. Today Commun."},{"key":"ref_97","doi-asserted-by":"crossref","unstructured":"Longhi, M.A., Zhang, Z., Rodr\u00edguez, E.D., Kirchheim, A.P., and Wang, H. (2019). Efflorescence of Alkali-Activated Cements (Geopolymers) and the Impacts on Material Structures: A Critical Analysis. Front. Mater., 6.","DOI":"10.3389\/fmats.2019.00089"},{"key":"ref_98","doi-asserted-by":"crossref","first-page":"122678","DOI":"10.1016\/j.conbuildmat.2021.122678","article-title":"Phase Changes under Efflorescence in Alkali Activated Materials with Mixed Activators","volume":"283","author":"Srinivasamurthy","year":"2021","journal-title":"Constr. Build. Mater."},{"key":"ref_99","doi-asserted-by":"crossref","first-page":"103886","DOI":"10.1016\/j.cemconcomp.2020.103886","article-title":"Progress, Current Thinking and Challenges in Geopolymer Foam Concrete Technology","volume":"116","author":"Dhasindrakrishna","year":"2021","journal-title":"Cem. Concr. Compos."},{"key":"ref_100","doi-asserted-by":"crossref","first-page":"21","DOI":"10.1016\/j.jobe.2018.06.002","article-title":"Effect of Calcium Stearate Based Foam Stabilizer on Pore Characteristics and Thermal Conductivity of Geopolymer Foam Material","volume":"20","author":"Cui","year":"2018","journal-title":"J. Build. Eng."},{"key":"ref_101","doi-asserted-by":"crossref","unstructured":"Walbr\u00fcck, K., Maeting, F., Witzleben, S., and Stephan, D. (2020). Natural Fiber-Stabilized Geopolymer Foams-A Review. Materials, 13.","DOI":"10.3390\/ma13143198"},{"key":"ref_102","doi-asserted-by":"crossref","first-page":"6958","DOI":"10.1007\/s10853-012-6644-3","article-title":"Synthesis and Mechanical Properties of New Fibre-Reinforced Composites of Inorganic Polymers with Natural Wool Fibres","volume":"47","author":"Alzeer","year":"2012","journal-title":"J. Mater. 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