Certainly the concentric circles were inspired by the shape and form of the tires themselves, and the easiest way of spreading them out so they could be filled with concrete.

Worn out tires arranged in concentric circles in front of a construction site. A building boom started in the early 1980s in Boston, and there were almost a dozen building sites at any given time. Here the workers have filled the car tires with concrete and sections of PVC tubing, so as to make bases for the fencing they would put up around the construction site. Here the construction workers have unwittingly created a work of installation art rivaling the best to be found on the art scene at the time.

Photographs of Boston.