Did you see the reports of that steel building fire/collapse in Sao Paulo this past week?
One reason I KNOW it’s possible is that when I was a boy, a six story steel girder and beam medical building was under construction near my house. They’d just completed the steel work and were building the wooden forms for the concrete flooring to be poured. They gotten the first three floors forms done when some high school kids took five gallons of gasoline (17 cents a gallon back then) and spread it around the forms on the first two floors and ignited it. The result was a four alarm fire. Open work, wood forms, and steel girders and beams, box construction. . . Plus gasoline and a good stiff easterly wind.
The next morning what was left of the building was a pile of steaming, smoking, bent and twisted steel. Nothing was straight and boxlike anymore, nor was it six stories tall. It was at most a pretzel shaped mass of curved junk about two to three stories tall. Every girder and beam was bent and twisted by the heat of that wood fire. They had to raze it and start over.
Steel structure after a wood fire
I don’t see any "melted" structural steel components, but there sure are a lot of BENT and TWISTED steel distorted by heat.
That’s pretty much what that under-construction medical building looked like after that arson fire. . . and there wasn’t that much wood in that one.