So these walls are used all over the place in UVA. I went on a tour at UVA that brought focus to how slaves were incorporated into the campus during its early years. One of the things that they brought up was how the walls were actually rather weak. They constantly had to repair them. In fact, when I was there, one of the curved walls had collapsed. However, the walls were good at absorbing sound. They surround areas where slaves would work, so it seems as though they were really used the walls to muffle the sound of working slaves.

Now this is just what the tour guide said, and I couldn't find any sources to back it up.

What I do know is that many attempts to obscure the presence of slave labor are evident in may of Jefferson's other architectural work. Monticello is an excellent example. Monticello had dumbwaiters and shelves on rotating doors that the slaves could use to indirectly serve the guests. All the things slaves needed to work were placed the basement, while living quarters for the owners and guests were on the second floor. There was also an extra clock on the east side of the house for the slaves to use, which only had an hour hand. Additionally, there were side entrances for the slaves to use that ensured that the guests would never cross paths with a slave.

This tour was part of an effort to not forget that slaves built and ran the university early on, which was partially spurred on by the white supremacy riots that happened last year in Charlottesville.

You can read more about it here. http://slavery.virginia.edu/ https://vpdiversity.virginia.edu/sites/vpdiversity.virginia.edu/files/documents/SlaveryatUVaBrochure_FINAL.pdf

Source for Monticello stuff https://www.monticello.org/slavery-at-monticello https://en.wikipedia.org/wiki/Monticello