You probably mean this: the First Battle of Rappahannock Station, also known as Waterloo Bridge, White Sulphur Springs, Lee Springs, or Freeman's Ford...
The Fauquier and Alexandria bridge / railroad went by many different names.
Edit - There was a bridge of the Orange and Alexandria Railroad at the Rappahannock Station battlefield, but that wasn't the same thing as the Fauquier and Alexandria turnpike bridge.
Hoosier