×
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

Plate for a man hole

Plate for a man hole

Plate for a man hole

(OP)
I have to design a plate acting as a cover for a man hole. It is 24"x24" supported on all sides. There is going to have heavy circulation over it. I know there is biaxial bending an torsion but dont know how to design it. Have any info on this design?

RE: Plate for a man hole

Order a manhole cover from a supplier.

RE: Plate for a man hole

First, I'll assume you're stuck with square, otherwise you really need to consider making it round so it can't be dropped in the hole.

For maximum moments and shears, check out Roark's Formulas for Stress and Strain.  They have that case in there (uniform load, pinned on 4 sides).

I think SperlingPE stated it best, however.  Find a Neenah catalogue and buy one.  It will probably be lighter than the one you come up with.

RE: Plate for a man hole

gotta agree, just buy one.

RE: Plate for a man hole

(OP)
Thing is that I work for a steel fabricator.  A simple plate for that use would be a lot cheaper than buying one from a supplier. It's more a well cover at the end of a floor gutter in an industrial building.  I would like to replace the traditional grating.

RE: Plate for a man hole

Try Roark's, or design it for one-way bending.  

RE: Plate for a man hole

There's a reason that you don't see steel covers in roadways.  Steel will tend to absorb energy by deforming.  Covers have to be fitted just right and overdesigned to handle the traffic load plus impact.  If either don't happen, the cover will warp, make a lot of noise and get worse.  
If there isn't a problem with leveling and the grating is in good shape, weld a plate to that.

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