The Shanghai building looks pretty open to airflow. The blast furnace effect required to achieve temperatures needed to soften steel should have been operating unhindered.

Some people believe the World Trade Centers were brought down by demolitions:

Next, we are shown an incredible bit of detective work on Torins part. He shows a sequence of 12 different pictures of the collapse initiation of the North tower, WTC 1. Torin explains that the antenna on the top of the world trade center is a perfect guide of measurement for height, as there is a standard of changing the paint color of antennas once per fifty feet. The part of the antenna on the roof of WTC 1 appears black, then white alternated every fifty feet. There is a guide wire in the bottom left of every picture that shows that the camera does not move. Why is this picture so interesting? It shows the antenna, which is held up by the core columns, fall before the rest of the building while the fire line on the 78th floor doesn't move. Torin then goes through the hard physics of the scene we're looking at and explains how it directly contradicts the official story, "This building is not collapsing on the 78th floor. The antenna falls 56 feet before the 78th floor falls."

http://nationalwriterssyndicate.com/index.php?option=com_content&task=view&id=128&Itemid=2

Lots of kooks out there, huh? I know there's a simple explanation for why the Shanghai building didn't fall. What is it?