Molded Sand And Cricket - Photography

A couple of years ago while in the farm with a friend spraying herbicides, I found these molded sand constructed by insects. What could have done that? Soldier ants?

Surprisingly, while taking the shots, a cricket showed up. It perched on one of those sands. I noticed it wasn't looking all right. One of its legs has been chopped off - probably by a predator. This creature as it stands, will find it difficult to survive in the wild.