×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Simple Wire Barrier Deflection

Simple Wire Barrier Deflection

Simple Wire Barrier Deflection

(OP)
I'm review materials to be used for a mesh barrier with a cable or wire border that will handle most of the loading, it must span 96", be fixed at both ends at an equal height, and be able to resist deflecting more than 4" at midspan by a force acting there of 20 lbfs perpenticular to the wire. I'd like to evaluate the possibility of preloading the wire to help with this 4" deflection requirement. I'm using the change in wire length (dL), assuming the loaded system is approximately two right triangles, at maximum deflection to give a wire tensile force (P) at this condition: P=dL*E*A/Lo. I'm then using this force to calculate the component that resists the perpindicular loading, and also the stress in the wire to evaluate if it would break/deform. I'm not sure where to include the term for preloading in this scenario. Can I simply add it to my P result to get a value for preload tension + tension from deformation? Is there anything else I'm missing here? Thanks for your help.

RE: Simple Wire Barrier Deflection

If I understand your problem correctly, preloading (or tensioning) your wire will not reduce deflection because the deflection will be determined by the tensile modulus of the wire. Basically the change in length of the wire is proportional to the change in load. Preloading does not change this relationship.

RE: Simple Wire Barrier Deflection

When you preload the wire, you will get a reduction in the cross sectional area of the wire. Then deflecting the center of the preloaded wire by 4", you can calculate the tension in the wire by using the reduced cross sectional area in your formula. In turn, you'll have a further reduction in the cross sectional area based in the tension of the wire; I would then average the two calculated cross sectional area and repeated the above calculation. You should be able to calculate the first reduced cross section area using poisson's ratio. There will be a bit of trial and error to get the value that you need.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources