What Is the Rise and Span of a Bridge?

[avito009]

As per me rise is the vertical length of the structure. Am I right? I read in Gordon's book "Structures or why things don't fall down" that the rise should be half the span of the bridge. Why? What does span mean?. As per me span means the area between one end where there is a column and the column at other end.

 

[Wee-Lamm]

Think of , Slope of a Line where the Horizontal access is run (span in your bridge),Vertical axis is Rise, and slope is the Delta of change in height over the length of the run.

As a primer for various bridge types, http://www.explainthatstuff.com/bridges.html

As you asked for layman's terms, perhaps discussing fulcrum points as they relate to weight distribution, would be a little premature. :-)