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!

*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

Foundation Design For Scour

Foundation Design For Scour

Foundation Design For Scour

I am trying to better understand the foundation design requirements for Scour.
According to the IDOT manual you would design your foundation based on Q100 flood and "check" the design based on Q500. By "check" they mean using a reduction factor = 1.0.
My questions are:
Is this correct? My example uses IDOT, but I would be glad to hear general comments.
If a flood level less than Q500 causes a water topping event, would you use this as your check? What limit states need to be checked in this event?



RE: Foundation Design For Scour

Here in Oklahoma I design for three scenarios. First, I check the foundation with the 100 year scour and the 100 year stream pressure (water surface at Q100), this would be the Design Flood in Section Second, I check the foundation with the 100 year scour and a dry stream. Finally I check the foundation with the Q500 scour and the 500 year stream pressure (water surface at Q500), this would be the Check Flood in Section The first two cases I check with Strength I,III,IV, V and Service I, which is probably overkill but it is done quickly with analysis software. For the 500 year event I only check with Extreme Event II per section and 3.4.1.

You can read in section about if you should use the overtopping flood versus the 100 year or 500 year event. For the design flood it is supposed to be the more severe of the 100 year or overtopping. The check flood can be the 500 year event or an overtopping event of lesser recurrence interval. My take on the check flood is you are trying to prevent the bridge from being washed away in a 500 year event.

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! Already a Member? Login


eBook - The Future of Product Development is Here
Looking to make the design and manufacturing of your products more agile? For engineering and manufacturing organizations, the need for digital transformation of product development processes just became more urgent than ever so we wanted to share an eBook that will help you build a practical roadmap for your journey. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close