I base my question on this question: What is this type of road called in English?
From that post, I learned that this kind of roads are called Switchback or Serpentine

By definition, a switchback is "a 180° bend in a road or path, especially one leading up the side of a mountain." Basically, it only represents paths of a "zig-zag" shape.
But what about a circular or rotating one like the below, which do not bear the "zig-zag" meaning?

