I think you can't do these analysis with satellite image. The only thing you can do is see if the bridge is there or not. Maybe, if the images have a good resolution, you can see some cracks in bridges, not much more.

Maybe you can try with photogrammetry or Lidar

It's difficult to do this. When acquiring satellite images, the resolution is taken into account. The bridge appears as a very small element occupying a minimum of pixels, this is because of the scale. It therefore becomes difficult to use this information well.