×
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

Box Culvert AASHTO-LRFD Loading

Box Culvert AASHTO-LRFD Loading

Box Culvert AASHTO-LRFD Loading

(OP)
I am trying to determine how the AASHTO-LRFD code wants me to determine the lateral earth pressures(EH)against the outside walls of an reinforced concrete box culvert due to Earth Loads and Live Loads(HL93).

I have a box culvert that has complicated and unconventional transitions from a single "horseshoe" box to a double and a double to a triple with varying heights etc.

1.)  For this type of structure I am wondering if Rankine or Coulomb method should be used for lateral earth pressures.(I've read some people who believe that one should use "At-Rest" earth pressures for RCB.) Do I need to apply the soil-structure interaction factor that AASHTO requires for vertical pressures?

2.)  How does the code want the live loads to be distributed on the walls.  The governing live load pressure on one of the transitions is 690 psf on the top slab.  Should I assume a surcharge height of 690 psf/120 pcf = 5.75 ft and apply it as a uniform horizontal load?

3.)  The soil borings indicate water will be present for a significant length of the 1700 ft structure.  Should I assume a Ko of, say 0.5, and find the soil pressure with Pe=0.5*(gamma soil - 62.4 pcf) + 62.4 pcf?

Thank you for your time.  Any information the forum can offer would be greatly appreciated.

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