## 2 Bibliometric Analysis  
To analyze the scientific literature on VMAs in construction materials, a bibliometric analysis was conducted using the Web of Science (WoS) database by Clarivate Analytics. The primary research questions for the bibliometric analysis were as follows:  
1. How has research on the use of VMAs in construction materials evolved over time? 2. Who are the prominent researchers, institutions, and countries actively engaged in VMA research? 3. In which scientific journals is research on VMAs/construction materials typically published? 4. What are the primary search keywords associated with the use of VMAs in construction materials? The data for the bibliometric analysis were obtained from the Web of Sciences (WoS) database in August 2023 using the following search keywords: \"VMA\" OR \"viscosity modifying admixtures\" OR \"viscosity modifying agent\" AND \"concrete\" AND \"cement\". A total of 2356 results were retrieved (Table 4). The analysis focused only on English articles related to construction materials and published between 2000 and 2023. Figure 1 illustrates the evolving trends in VMA and construction materials research, reflecting a significant increase in publications in 2017. This upward trend suggests a growing focus on these topics, with researchers likely to continue exploring them in the coming years. Notably, 61.1% (369 out of 604) of articles were published between 2017 and 2023. Among this percentage, 23.7% (143 out of 604) were published in the journal Construction and Building Materials. In Figure 2, the top 10 journals contributing to VMA and construction materials research are highlighted. Among these, 54.6% (330 out of 604) of articles were published in the following journals: (1) Construction and Building Materials (23.7%, Elsevier, Impact Factor: 7.4); (2) Journal of Materials in Civil Engineering (5.8%, ASCE, IF: 3.2); (3) Cement and Concrete Research (5.6%, Elsevier, IF: 11.4); (4) Cement and Concrete Composites (4.5%, Elsevier, IF: 10.5); (5) ACI Materials Journal (4.0%, ACI, IF: 1.83); (6) Materials (3.3%, MDPI, IF: 3.4); (7) Transportation Research Record (1.82%, Sage Journals, IF: 1.7), (8) Materials and Structure (1.5%, Springer, IF: 3.8); (9) Applied Sciences (1.2%, MDPI, IF: 2.7), and (10) Advances in Materials and Civil Engineering (1.2%, ASTM, IF: 1.4). Research in the field of VMAs/construction materials has received contributions from 69 countries, as illustrated in Figure 3, showcasing the global distribution of publications counts. China emerges as the most productive country, contributing 163 articles (27.0%), followed by the USA (115 articles, 19.0%), Canada (54 articles, 9.0%), India (42 articles, \begin{table}
\begin{tabular}{c c c} \hline \hline
**Search Query** & & **Results** \\ \hline Search date & 23 August 2023 & \\ Search topic & “VMA” OR “viscosity & 2356 \\  & modifying admixtures” or & \\  & “viscosity modifying agent” & \\  & and “concrete” and “cement” & \\ Publication years & 2000–2023 & 2312 \\ Document type & Include only articles & 1181 \\ Language screening & Include only English & 952 \\ Research area & Include only research aeras & 604 \\  & related to construction & \\  & materials & \\ Data extraction and analysis & & 604 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Web of Science search query. Figure 1: Temporal evolution of total articles in the WOS database about VMAs/construction materials materials. 7.0%), France (41 articles, 6.8%), Poland (31 articles, 5.1%), Spain (24 articles, 4.0%), Turkey (24 articles, 4.0%), Germany (21 articles, 3.5%), and Iran (17 articles, 2.8%). These 10 countries collectively account for 88.1% of publications in the VMA and construction materials field. This high level of contribution from certain countries may be attributed to factors such as their large populations, active commercial activity, a high demand for construction materials, and a significant number of scientific research institutions.