×
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

New RC frame on top of existing

New RC frame on top of existing

New RC frame on top of existing

(OP)
I m dealing with 2 existing RC frames. I have to design new RC slab on top of that.
Above that is another floor - another RC frames on top of existing (columns are 300 x 300 mm, spacing between them is approx. 3 m).

Im wondering is it ok to anchor rebars for new columns in new RC slab as shown below?
I dont think that rebars would be properly anhored if I drill holes in existing columns + epoxy them.

Also it would be hard to get sufficient anchor lenght (drilling) which is needed since it will be desingned as moment frame. I want to avoid drilling in existing columns since I dont want to demage existing reinforcement there.



RE: New RC frame on top of existing

You need some kind of anchorage to the existing columns or beams. You have overturning and shear to resolve into the existing members. Either via the new slab or the new columns.

I'm not sure if you intend to do this, but it looks like you want to consider the bases of your new columns fixed. That's not really the case, especially if you only anchor them into the slab. That slab can rotate and isn't truly "fixed." Even if you epoxied the new column reinforcement into the existing columns it's not truly "fixed." That joint can rotate. If the loads are small, sure it's not much rotation, but it does rotate.

Do you have frames in both directions?

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