In the context of urban planning and road infrastructure, "eixo articular" can be translated into American English as "articulation axis" or "connecting axis." This term refers to a road or thoroughfare that serves as a key connecting point within the transportation network, linking areas with different levels of road hierarchy. Given the technical nature of the document you're translating for an audience of professionals and researchers in the field, the term "articulation axis" would be appropriate. It captures the function of these roads or paths as critical links that facilitate movement and connectivity between different parts of the urban and interurban landscape, especially in relation to a federal highway ("BR-XXX") in your example. (from ChatGPT-4)

https://publications.pages.asam.net/standards/ASAM_OpenDRIVE...
Connecting roads link the roads that meet in a junction. They describe the paths that a vehicle can travel across a junction. Connecting roads are modeled in the same way as standard roads. The paths described by a connecting road is based on its lanes.

:)

https://www.linguee.com.br/portugues-ingles/search?source=au...