Comment: Total reset?

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Total reset?

Where are you getting this idea about "total reset and reboot" being needed? I'm not a structural engineer, but from my reading of the building code discussions and proposals, the response to WTC 7 was continuous with prior ideas about protecting steel-framed buildings from collapse. The changes are about addressing the reasons that the WTC 7 fire couldn't be suppressed, factors that made it worse (the fuel storage in the building), and increasing insulation requirements to add more margin of safety in case of fire. Given that they are taking the official report at face value, what more do you expect?

Maybe you're thinking that in response to 9/11 they should have banned the long-span beams that were used in WTC 7, required new buildings to use concrete cores, etc? If you read the discussions on the site I think you can see why. The quote below is from a proposed change. It's clear that they're aware that "innovative structural design" using longer spans involves greater risk (and thermal expansion is just one aspect of this that they mention). But sometimes people want to push the envelope, so instead of going with safe but boring, they allow for innovative structural design while mitigating risks.

The purpose of the code change is to include new text such that performance based design of structural steel frames can be proposed on projects. This means that the IBC would allow performance based design for fire resistance similarly to other international codes for example in the UK, Europe and Australia. Also to recognize that the performance of structural members in a real fire can be very different to the fire resistance of single members i.e. a beam, column or slab acting in isolation of the rest of the frame in a standard furnace.

This is important because savings in structural fire protection can be made when structures are robustly designed but also weaknesses in the structural frame which can exist when thermal expansion forces act on a structure during a fire can be identified and designed against. This is particularly important in innovative structural design and iconic buildings which are generally much taller or have longer spans and cannot be adequately tested in standard furnace tests. The methodology however is applicable to any structure