×
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

Foundation Design

Foundation Design

Foundation Design

(OP)
I am attempting to design a small foundation for a light pole.  The pole is 4" square and 25' tall and must with stand a 120mph wind.  Need help please.

RE: Foundation Design

Usually, light poles are supported by small, drilled concrete piers of sufficient diameter to allow proper bolting of the pole to the pier.

The design involves considering the lateral forces on the pier and the desired amount of lateral deflection that can be tolerated.  A geotechnical engineer can help with this in terms of allowable stresses on the soil and determining an appropriate soil modulus to measure its stiffness.

Your local municipality may also have some set standards for light poles, traffic poles, etc. that you could utilize.

RE: Foundation Design

See Gaylord & Gaylord, "Structural Engineering Handbook".  Look under signs in the index.  They have a chart for drilled piers for light poles.

RE: Foundation Design

Use the wind code to determine wind coefficients/drag forces that will impact on the pole - Usually a manufacturer can offer some data on this issue.

Design foundation for resultant shear and bending forces such that foundation contact area is always under positive (compression) pressure over entire area.

Bearing capacity of coastal soils which are usually sandy is best determined by the standard penetration test (SPT) method. Care must be taken with the proximity of the water table.

RE: Foundation Design

Also check out the AASHTO Publication "Standard Specifications for Structural Supports for Highways Signs, Luminaries and Traffic Signals". It has a lot of information that will help you out.

Matt

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