×
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

Fibermesh - Tension Capacity

Fibermesh - Tension Capacity

Fibermesh - Tension Capacity

(OP)
Ok, I have an odd situation where I'm putting 6" by 6" steel bollards at 1' o.c. in a concrete trench (1'-4" wide by 4' to 6' deep). The bollards are rotated 45 degrees so they are diamond shape in plan.

I'm worried that a crack will occur between the bollards, propagate down into the foundation and compromise the integrity of the fence over time. The only reinforcing in the fence will be wire mesh at full depth on each face of the trench running longitudinally the length of the trench. There is presently nothing called out to tie the two faces together.

I proposed that a #3 rebar be added between bollards to tie each face together and keep the crack from occurring or spreading. The bar would tie to two #4's, one on each face of the trench running the length of the fence.

And this proposal has caused much pain and suffering. I'm now looking at every possible alternative.

One thought (not mine) was to replace the #3 with fibermesh in the concrete. I've only heard of fibermesh being used in slabs. To research this I need to know what the tension capacity is of the mesh to see if it is sufficient to replace the #3. My gut says it won't work but I need to look into it. Any thoughts?  

RE: Fibermesh - Tension Capacity

The bollard itself will connect the two faces if the mesh is attached to the bollard corner.

RE: Fibermesh - Tension Capacity

(OP)
The mesh will not be attached to the bollard. It will only be tackwelded every 8' or so.  

RE: Fibermesh - Tension Capacity

Structural fibers may be able to provide enough tensile capacity.  Contact Fibermesh or another supplier and talk to their engineers.  We saw a presentation in the office recently from Fibermesh.  They have plastic fibers now that are capable of developing enough tensile capacity to be used structurally, even to replace shear reinforcement.

This will require careful mix proportioning to preserve workability, though, and may exceed the cost of placing the transverse bars.

Traditional fibrilated poly fibers will not prevent structural cracking.

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