The World Trade Center cross, also known as the Ground Zero cross, is a formation of steel beams found among the debris of the World Trade Center site in Lower Manhattan, New York City, following the September 11 attacks in 2001. This set of beams is so named because it resembles the proportions of a Christian cross.

2024年3月7日 · The World Trade Center used 12 different grades of steel with yield strengths of up to 100ksi. The thickness of the steel in the towers' external walls varied by height, with lower levels using steel up to 4 inches (10 centimeters) thick and higher floors using steel as thin as 0.25 inches (6 millimeters) inches to optimize support against ...

flange beams, and the thinning of half-inch-thick flanges to almost razor-sharpness in the World Trade Center 7 steel. The New York Times called this “the deepest mystery uncovered in the investigation.” NIST left all of this crucial forensic evidence out of its report. Why? Because it didn’t fit in with the official conspiracy theory.

The towering twin steel beams were once part of the facade of the World Trade Center's south tower, sheathed in smooth aluminum. Salvaged from ground zero after the 9/11 attacks, the tridents are being resurrected and will greet visitors as …

This piece of steel is from one of the eight buildings that comprised the World Trade Center. It potentially came from an elevator system or a subway rail.

Abstract: This paper summarizes the primary structural systems that comprised World Trade Center 1, World Trade Center 2, and World Trade Center 7, which were destroyed in the terrorist attacks of September 11, 2001. There were four major structural subsystems in the towers: the exterior walls, the core, the floor system, and the hat truss.

2003年7月1日 · The problem of the airplane wing cutting through the exterior columns of the World Trade Center is treated analytically. The exterior columns are thin-walled box beam made of high strength steel. The complex structure of the airplane is lumped into another box, but it has been found that the equivalent thickness of the box is an order of ...

WTC firefighters shocked by a loud explosion. The linear shaped charge demonstrates the sound made by high velocity explosives. The sound which shocked the firefighters is all but identical, thus indicating it was created by a high velocity explosive detonation. Why were high velocity explosives detonating in the vicinity of the World Trade Center?

The steel beams in the debris pile and other remnants of the collapsed Twin Towers took on a special significance. During their down time, some recovery workers created symbols and shapes out of the fragments of steel, including crosses and Stars of David.

2016年9月8日 · In the years since the 2001 terrorist attacks on the World Trade Center, fire departments, museums and other groups across the country and the world have accepted pieces of steel, damaged cars...