In the 90s, I was talking about this problem to a structural engineering professor. He observed that they now had computers fast enough to do Monte Carlo simulations of buildings where the strengths of the beams and fasteners (and the number of bolts correctly inserted) can be varied. Then you see if it falls down under the design load.
I asked whether it gave different answers than the standard 1.5 safety factor. As I expected, the answer was yes. It turns out that in a conventional skyscraper, there is a tiny proportion of the structure that needs to be done right. This is good news as you can x-ray those beams, and check and double check that all the bolts are installed correctly. The cost to do this is tiny. The rest of the building can be built with an effectively smaller safety factor, and it will be fine. This leads to overall cost reductions.
I asked whether it gave different answers than the standard 1.5 safety factor. As I expected, the answer was yes. It turns out that in a conventional skyscraper, there is a tiny proportion of the structure that needs to be done right. This is good news as you can x-ray those beams, and check and double check that all the bolts are installed correctly. The cost to do this is tiny. The rest of the building can be built with an effectively smaller safety factor, and it will be fine. This leads to overall cost reductions.