How Building Implosions Work

Explosive demolition is the preferred way to bring down large structures. When a building is surrounded by other buildings, it may necessary to "implode" the building onto its footprint. Engineers in foreign countries were showed the video of the World Trade Centers collapsing with no knowledge of the 9/11 attacks. They all stated that they were convinced the buildings were intentionally demolished. Yet when they were eventually told the real story, they were shocked. The World Trade Centers demonstrated a picture perfect controlled demolition in the way they collapsed. Yet, the fires from the fuel of the planes are still stated to have caused the steel to collapse in the buildings. The basic idea of explosive demolition is quite simple: If you remove the support structure of a building at a certain point, the section of the building above that point will fall down onto the part of the building below that point. The explosives are just the starting point of the demolition, gravity actually brings the building down. Demolition teams load explosives at multiple levels of the building to ensure the structure falls down on itself on multiple points. When a building is surrounded by other structures that need be preserved, the demolition must be laid out carefully. The lower floors are detonated first, then a floor in the middle and top of the structure usually follow. For example in a 20 story building, the 1st and 2nd floor would be detonated first, then following this explosion the 12th and 18th might be detonated. This formula usually causes the building to collapse on itself. Note that right before the WTC collapsed, there was a large explosion on the 1st floor of the building. Makes you wonder huh?