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How to calculate the impact energy of a door hitting a door

  1. Jul 3, 2015 #1
    Could someone help me with this problem?

    I have a scenario where a glass door is being caught by the wind and slamming against a door stop and shattering. I would like to work out the impact energy of the door hitting the stop, and if possible an equivalent static force.

    The door is 1.5m wide, 3.0m high and constructed of 15mm glass, (170kg total weight).
    The wind load is 2.14kN/m^2
    The door opens 90 degrees with the door stop 350mm from the pivot. The pivot is 100mm in from the edge of the door.

    Thank you.

    Attached Files:

  2. jcsd
  3. Jul 3, 2015 #2


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    Can you find any relevant equations? Can you draw a free body diagram?
    Do you think your employer would approve you seeking solutions to problems on their pad?
  4. Jul 4, 2015 #3


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    I don't believe it's possible to calculate a solution with just the info given.

    The force will depend to a great extent on the properties of the door stop and the door. If you assume the door stops moving the instant it hits the stop then the calculated force is theoretically infinite. Obviously the door doesn't stop instantly. I suspect what happens is that the bottom of the door stops quickly but the centre of mass of the door continues and this twists the door. In effect you have a glass torsional "spring" that decelerates the door.

    There is probably a way to calculate how the door moves when it hits the stop but it will be quite complicated - too hard for me!
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