Forces in truss members greater than applied force?

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sukibelle
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I've had to conduct an experiment with strain gauges attached to each member and when I've calculated the forces in the members I've come out with really large forces in comparison to the applied force.. how does this work out?
 
Yes that quite often happens that individual member forces exceed applied loads in certain directions.


In fact if you think about it, it sometimes becomes inevitable.

Consider the simple hanger shown in the attachment.

T is the only vertical force supporting weight W. But T is not vertical so must be greater than W to exert a vertcal component equal to W.

go well
 
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  • Hand-drawn free-body diagram of a hanging weight: a wall on the left with an inclined cable to a point carrying weight W, a horizontal force F, angle alpha marked, tension T along the cable, and written working below stating T = W / cos alpha so T > W.
    sup1.jpg
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