GG I believe the column has been cut with an oxy torch/lance during demolition stage The resulting slag would have been dislodged if it was cut before the collapse as everything came crashing down on it, whereas it looks all intact to me. There are pictures of columns being cut on an angle during the demolition the web somewhere I have seen them.
Here is a link to a rather long but quite well worth reading report if you are interested in knowing the real perpetrators of the event, certainly way more creditable than any of the rubbish Governments would have you believe. Shame on Julia.
