×
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

Stair Pan Analysis

Stair Pan Analysis

Stair Pan Analysis

(OP)
I'm checking the design of a steel pan for a staircase. It consists of an 1/8" steel plate with 3" unreinforced concrete.  
The stringers are 4'6" apart, and the length of the landing is 6'-0"  
Should I consider this plate supported on 4 sides acting as a 2 way slab, or a one way slab spanning the 4'6"?
And, do I consider the concrete as acting?

RE: Stair Pan Analysis

2 ways to approach....
1)  Neglect the concrete, compute the bending as simply supported beam.  Check shear on the welds at the stringers.  Don't worry about deflection, the concrete will fix that.

2) Analyze as simply supported concrete beam.  It is too narrow to act as a slab.

RE: Stair Pan Analysis

It might help if the top lip has 1/4" or so bars across or straps to stabilize the bent steel channel toe.  3" deep x1/8" thick may tend to buckle.  If salt use is an issue, keep sufficient cover to protect the ties, else the steel expansion caused by corrosion can spall the concrete... have seen this happen (also with old time nosing bars).

RE: Stair Pan Analysis

(OP)
Thanks,
Am using a thicker steel plate - with underside ribs.
Also found that The AISC Manual Pg. 2-145 is a great help in plate sizing.
It's for simple supported plates.  If anyone knows of the moment factors for plates supported on 3 and 4 sides for different length to width rations, it would be appreciated.  

Thanks Again!

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