Although the rocker plates were ripped free of the pier by lateral deflection, the end placement of the kingposts indicates they rotated about their bases, displacing the tops of the piers little if at all.
On the other side, you could be right, but the tension in the cantilever trusses would come as a result of the lateral deflection, not an increase in pier to pier distance as the piers at the failure point didn’t move.
A good strong jerk along the cantilever steelwork could begin the pier deflection process, which could continue as the sidespan adjacent to it fell and kept shoving them towards the river.
Not real impressed with those piers, I don’t see much more concrete than necessary for vertical load bearing, not a lot of lateral stability there, they appear to leave that to the steelwork above.
Still, it’s clear that the triggering event initiated on the far side.
On the other side, you could be right, but the tension in the cantilever trusses would come as a result of the lateral deflection, not an increase in pier to pier distance as the piers at the failure point didn’t move.
Ummm...huh?