×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Contact US

*
*
*
*

Thanks. We have received your request and will respond promptly.

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

new RC slab with existing columns

thread507-429372

new RC slab with existing columns

new RC slab with existing columns

(OP)
Im dealing with a new concrete slab that is 120 mm thick.
Slab is supported on existing walls and on new masonry wall that is made between existing RC columns (300 x 300 mm)
Im wondering should I:

OPTION 1: anhor (rebars) new slab in the middle to the existing columns. I would use very small diameter of anchors/rebars so columns wont be affected much

OR

OPTION 2: dilatate new slab from existing columns (20 mm of insulation between slab and column)


What do you guys think? what is better. I know that a slab capacity is not problematic since spans are small and it is supported, but what about cracks between columns and edges of a new slab?


RE: new RC slab with existing columns

Your new slab will shrink the most in the long direction (parallel to the long walls). I like your option 2 of separating the slab from the columns, if they are not needed for support. Put some diagonal reinforcing in the re-entrant corners of the slabs near the column block-outs to help control cracking there.
Dave

Thaidavid

RE: new RC slab with existing columns

Can you use a rebar locator to find the column bars and core drill through the existing column to install 'through dowels' assuming the column is small... and use 1/2" flexcel to isolate the slab on three sides from the column?

Dik

RE: new RC slab with existing columns

I see no reason to connect it to the columns. All your gravity and lateral support comes from the walls.

RE: new RC slab with existing columns

DETStru: Correct... I thought there were beams between the column... just isolate around the columns...

Dik

RE: new RC slab with existing columns

(OP)
I ll isolate.
thanks for help!

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

Resources

Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a part’s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. 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