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Spring Positioning on a Cantilever beam

  1. Jan 16, 2013 #1
    Hallo guy,
    I hope its not asking too much, but i really need help with this, Urgently.
    I have a cantilever, with point load P=100 at the end tip.
    A spring(K=500) attached to the cantilever perpendicularly at UNKNOWN position.
    I KNOW the deflection at the end tip. and the rest of the parameters, the only thing UNKNOWN is the POSITION where i can place this spring to generate the known deflection at the tip.
    Can somebody help me formulate a formula which can help me get this position.
    I will appreciate your help guyz, am really stuck on this.
    I hope its well understood, if not, i can generate a drawing and attach it.
    Thank you guyz.
  2. jcsd
  3. Jan 16, 2013 #2
    Urgent or not, is this coursework?

    If so post your efforts so far in the homework forums.

    You should be able to find an expression for the distance of the spring from one end (call it s) and solve the expression for s.

    Hints, there are several ways to do this - the cantilever is propped and therefore statically indeterminate.
    You can use direct force methods to solve the beam equations or use indirect energy methods.
  4. Jan 16, 2013 #3
    Thank you, i will do that next time.
    The cantilever is fixed at the far end and the force is at the tip, the spring should lie and attached to the beam perpendicularly.
  5. Jan 16, 2013 #4
    So what do you know about cantilevers and statically indeterminate structures?

    Do you understand superposition?
    Last edited: Jan 16, 2013
  6. Jan 16, 2013 #5
    Yes i do understand the Method of superposition. its the method i was trying to evaluate the problem with
  7. Jan 16, 2013 #6
    So what do the equations you are trying to superpose look like?
  8. Jan 16, 2013 #7
    I got the solution already, Using the Superposition formulas, i did some manupulations, used excel to solve a polynomial and cross-checked my Analytical process with FEA software.all is well.
    Thank you.
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