One thing that has stuck in my head is the actual footprint the towers actually had. The dimensions? 208 ft. by 208 ft.(63m x 63m)for each tower. Otherwise, each tower, for all their worth, occupied only one acre of land.
I've read they DID design the building to take a collision from a jetliner. Structurally, it held, until the intense heat from the flames caused the trusses to sag and eventually fail. When they failed, one floor fell on the floor below, which caused it to fail and fall to the floor below. Within seconds, there was a substantial part of the building in freefall.
Trusses are tremendously strong, as a composite structure. Unfortunately, since they are made with lightweight components, heat will cause them to fail long before the melting point of steel. All they have to do is become plastic, which happens at a temperature below the heat from a wind fed petroleum fire. Since they have only a few connection point due to their ability to bridge large distances, any failure is catastrophic.
That is bizarre.
ReplyDeleteOne thing that has stuck in my head is the actual footprint the towers actually had. The dimensions? 208 ft. by 208 ft.(63m x 63m)for each tower. Otherwise, each tower, for all their worth, occupied only one acre of land.
They should have made it wider and lower. Plane would have went right over.
ReplyDeleteHindsight, and the cost of real estate in the New York city business district.
ReplyDeleteThey never dreamt that would happen.
ReplyDeleteI've read they DID design the building to take a collision from a jetliner. Structurally, it held, until the intense heat from the flames caused the trusses to sag and eventually fail. When they failed, one floor fell on the floor below, which caused it to fail and fall to the floor below. Within seconds, there was a substantial part of the building in freefall.
ReplyDeleteTrusses are tremendously strong, as a composite structure. Unfortunately, since they are made with lightweight components, heat will cause them to fail long before the melting point of steel. All they have to do is become plastic, which happens at a temperature below the heat from a wind fed petroleum fire. Since they have only a few connection point due to their ability to bridge large distances, any failure is catastrophic.
Jess, you know your stuff, I give you that!
ReplyDeleteAnybody else notice the three Arabs in the middle trying to figure out which direction to pray? And this is from 1982? Talk about prophetic.
ReplyDeleteThat's so freaky.
ReplyDelete