The pilot had just completed one touch-and-go landing and was performing his second one when he touched down with 500 feet of runway remaining. The airplane had excessive speed due to the unstabilized approach, and the pilot applied maximum braking at the last 50 feet of runway. The airplane went through a ditch and came to rest on a grass embankment next to a barbed wire fence which resulted in substantial damage to the right horizontal stabilizer and right elevator. The operator reported that there were no preaccident malfunctions or failures with the airplane that would have precluded normal operation. The operator further reported that the accident could have been prevented if the pilot had executed a go-around due to the unstabilized approach or may have been prevented if he had applied maximum braking at the point of touchdown.