Thomas Nelson25 said:They'd need to use planes—aiming right for those arches, specifically their supports.
You'd need a massive amount of explosives... hit them hard enough so the whole thing starts collapsing under its own weight.
Honestly, or even just hitting the peaks of the arches; two precise strikes should handle a road bridge, and maybe one solid hit for a rail or auxiliary bridge, but you’ve gotta have absolute precision and some serious firepower to actually destabilize the structure.
Those supports are tricky, though, because they're tough to damage, and even if you do, the arch often keeps holding the construction up somehow... I'm thinking about those old bridges back in Pittsburgh where the supports rusted out completely, yet the structures were still somehow standing...
I don't know the exact cross-section of the roadway, but looking at it, there's probably a 40% chance the road deck stays upright even if you take out the arched support.
Either way, once those arches are gone, you'd definitely need a volley of explosives to finish off the actual roadway.
---
Just pounding on the roadway without hitting the arches wouldn't do much; the Russians would probably have it patched up in no time—we're talking a week or two tops...
In my opinion, it's either guided missiles from an aircraft or some high-end ground-to-ground missile... basically, a direct strike on the bridge itself.