for my StreetConstructor I've uploaded a new parameter file for creating concrete bridges. The concrete texture is from Giants from the original game. You can also similar driveways for parking garages make you fall ... certainly other options a.
If you like, the bridges can be provided even with railings (I imagine even in)
Suitable pillars are also found on Modhoster ...
Looking forward to many interesting maps :-)
Giants: Beton-Textur "asphalt_diffuse.dds"