*3.6. Countries*

Several countries have contributed more to current research than others have and are expected to contribute further. The network map was created to allow readers to view areas committed to the research of RHA concrete. "Bibliographic coupling" was selected as the "kind of analysis", and "countries" as the "unit of analysis". The minimum document limit for a nation was set at 10, and 27 countries met this requirement. The nations listed in Table 5 have published at least ten documents in the present study field. India, Malaysia, and Thailand presented the most papers with 293, 133, and 48 documents. Moreover, these nations received the most citations, with Malaysia receiving 3104, India receiving 3098, and Thailand receiving 2049 citations. Figure 10 illustrates the visualization of the science mapping as well as the density of nations connected via citations. The size of a box is proportional to a nation's effect on the subject research (Figure 10a). The nations with the most engagement had a higher density, as indicated by the density visualization (Figure 10b). The statistical and graphical analysis of the contributing states will aid emerging researchers in establishing scientific alliances, forming joint ventures, and exchanging innovative techniques and ideas. Researchers from nations interested in promoting research on RHA concrete can work with experts in the field and profit from their experience.


**Table 5.** Leading countries based on published documents in the present research area until 2021.

**Figure 10.** Scientific visualization countries with at least ten publications in the related research area up to 2021: (**a**) network visualization; (**b**) density visualization.
