When a Fond du Lac man decided to vault over a concrete barrier in a downtown Madison parking garage, he thought he would land on a surface at the same level.  Instead, the 32-year-old fell several stories to a set of railroad tracks below.  The incident happened Thursday at about 2:40 a-m at a Monona Terrace parking structure.  He was with a group returning to their hotel from a bar.  The man’s name hasn’t been released.  He is expected to recover from his injuries.