Angled steel and controlled demolition!


DON'T BELIEVE YOUR LYING EYES!

Ground zero on 9-11, what is that 45 degree perfectly cut steel beam doing there?


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Controlled demolition, especially for steel-framed buildings, demolition teams set explosive charges to cut steel beams at precise angles, typically around 45 degrees. This angled cut helps in several key ways:


Why the angled cuts?

  1. Directional Collapse: Cutting at an angle helps control the direction in which the beam—and thus the structure—falls.


  2. Sliding Effect
    : Angled cuts allow the upper sections of steel to slide off more easily, speeding up the collapse and avoiding resistance.


  3. Signature of Cutting Charges
    : The classic 45-degree angle is characteristic of cutter charges, such as linear shaped charges or thermite devices, which can slice through steel with high precision.


Real-World Use

Demolition experts plan these cuts strategically on load-bearing columns and beams throughout the structure, including the core columns and perimeter supports, to ensure the building falls vertically into its footprint with minimal collateral damage.

Would you like a diagram or example from a real demolition?


What are these doing at ground Zero, and why did they clear the debris so fast?