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!

*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.

Jobs

Max. wall deflection

Max. wall deflection

(OP)
What could be the max. allowable deflection for the retaining wall shown in the attached? Is the allowable deflection for this condition indicated in the codes? To develop active pressures, I think that a movement of 0.001H can be considered (for granular backfill), so I was planning to use this as the max. allowable deflection. We need to check with the designer, but perhaps he considered at rest pressures to design that wall since the 2F slab restraint movements of the wall. But, I think that since the wall is constructed first and then backfilled, some deflection can be allowed.

BTW, the construction sequence will be:
1. Construct the retaining wall
2. Backfill
3. Construct the Slab on grade
4. Construct the 2F walls

So, concern is about the needed to brace the wall on the top to limit deflection. But if deflections are within the allowable deflection, bracing may not be required.

Do you see any other issues or do you think that the construction sequence can be improved?

Thanks !!

RE: Max. wall deflection

There is no Code requirement I am aware of for the movement in the retaining wall you describe. All the components need to be able to accommodate the potential deflection, and the wall itself needs to account for the added eccentricity of gravity load from the building above resulting from the deflection.

RE: Max. wall deflection

(OP)
dcarr82775, Do you think that is reasonable to consider that bracing may be required because the walls were designed based on at-rest pressures, so they were designed assuming zero deflection of the wall?

RE: Max. wall deflection

(OP)
Other option is to backfill (at the same time) both sides of the wall to balance/avoid excessive wall top deflections. Then remove the soil at the road side after the building slab is completed.

If there is an allowable maximum deflection, then we will not need to backfill for the entire height of the wall at the road side (assuming that we are using the same type of soil in both sides).

My doubt is about what type of pressures do I need to consider in both sides of the wall.
I think that the correct way should be to consider active pressure at the buidling side (left side of the wall, since we will backfill up to the entire height of the wall) and passive at the road side (assuming that there is some allowable deflection, so we will have only a partial backfilling, since we will not backfill the entire height of the wall).

My first approach was to consider active in both sides, which it may not be correct.

Do you think that this can be a viable/correct option?




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


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