You’re talking about the curvy road before they bridge? It’s because people inherently slow down when turning and they want people to reduce their speed over the bridge to reduce the stress in the bridge meaning it’ll require less maintenance over time.
nope if so every bridge would have curves its because it was a old bridge to the right they left the old one open until completion of new one then curved the road to the new one . i build mechanical bridges for cec huvall and huvall in lafayette louisiana we do it all the time .