Reply #169: Reserve capacity of the core...

[Carefulplease]

On edit: Explicitation of "design loads".

I did not mean to imply that you said that the core resisted the wind loads. I meant to point out that the core not having to carry the wind loads meant that it was designed with less reserve capacity than the perimeters walls (on a non-hurricane day)

The actual reserve capacity of the core might be closer to 100% based on demand-to-capacity ratios listed in the NIST report. This is based on the actual loads and the actual strengths of the steel components. My 30% figure must come from DCR ratios that are based on design loads and nominal strength of the steel components. The later have intrinsic safety factors. The former include live loads that are about four times what they were on 9/11 2001 (Hoverer, the bulk of design loads of core columns are dead loads). This would account for the discrepancy. I'll do some more research when I have some free time.