This is a gee whiz I've never seen that before, wish I had a camera, what are those tractors called?
They are building a new expanded Speedway near a business I go to about twice a week, and so have been watching the construction. The company doing the construction has an almost infinite stable of heavy and light pieces of equipment, and the ones in use change by the minute. Besides all the usual dozers, backhoes etc, there are ones that articulate in the middle and apparently both ends steer, and the biggest rototiller device I've ever seen, the guy drove over construction debris, clods, mud, lumps rock etc, and what came out was like flour. Then another big heavy roller device could compact it. Tiny micro track hoes, and today a giant one poised over a drainage swale hundreds of feet deep and wide, and I'd really like to see how he got back to the other side. The oddest so far was a device into which a cement mixer unloaded cement, and which went along very slowly and out the back end came a gutter curbing laid down perfectly shaped, just like you'd pipe frosting on a cake. No forms no nothing. Amazing!