I am rethinking the shear surface. The skid marks and impact on the pier are along each side not in the center where the extension of member 12 would have impacted and slid. Perhaps the failure occurred through the white pipes with red on top. The photo of the NTSB worker digging through the...
There appears to be a cold joint in 11-12 at the top of the deck. See photos above. If the PT rod(s) is anchored below that point, somewhere lower in the deck, and you increase the PT force, you increase the shear along the cold joint.
Thanks Meerkat. PT ducts are tougher than I thought and the widely spaced ties are not as ductile as I imagined. I envisioned member 11 looking like a centipede where the PT ripped out.
Please forgive me if I missed this in skimming the previous threads but:
-I noticed the PT sheath that I assume is from member 11 is nearly intact. I would think it would be destroyed as it ripped out.
-Maybe the old eyes missed it but if the PT strand was within the ties of member 11, I would...
