These images seem to be well taken technically, sharp, good exposure, no lens distortion etc.
I suspect that these shots showing the ground under the bridge would be more effective if you were able to capture the bridge from a location where the water under the bridge predominates. As well, I find it a little confusing as what is the point of interest, is it the road or the birds? rather than the bridge. Also, a shot which shows off this massive civil structure would be more dramatic. Such as the size and the height of the towers, length of the main span or the symmetry of the cables and stays.
Hope this helps.
Joe