Unnecessarily complex shape? 

Is there some particular reason for building this bridge the way they did? A form of aesthetic appeal? Is the bridge particularly high, so more run-up length is needed to get vehicles up to the required height?

It looks like nearly all of the bridge is raised on support beams, which increases costs due to need for stabilization and heat expansion compensation.

A much simpler and less expensive design would apparently have been a Y shape with one lane passing under the other. With a Y-shape, the entire structure could have been built on earthwork mounds, except for where the one crosslane bridge passes over the other.