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

Steel Floor Framing over Concrete Columns and Walls

Steel Floor Framing over Concrete Columns and Walls

Steel Floor Framing over Concrete Columns and Walls

Hi All,

I recently engineered two schematic for a two story over podium project. The owner wanted two designs for the podium: 1) concrete PT with conc columns and shear walls and 2) all steel with pan deck with steel columns and bracing.

Now they want us to look at hybrid version - Concrete columns and walls supporting Steel Framing and pan deck.

I haven't done that type of system, dont like it, and already told the owners that it will be more complicated due to more trades and coordination, but they still want to persue.

I am looking for some pros and cons of the steel framing over concrete columns and shear walls.

RE: Steel Floor Framing over Concrete Columns and Walls

Is this a single story podium for parking?

If so, concrete columns/walls will be more robust and, if hit by a car at low speed, is less likely to be seriously damaged (though you could pick a steel section that would win that fight, too). So I could see some logic there - nice, fat, resilient concrete columns are cast, and when they reach sufficient strength, you have a floor system that requires zero temporary form work and zero shoring.

RE: Steel Floor Framing over Concrete Columns and Walls

Yes. This is for a single story podium with parking below.

One of main concerns is the connection at the top of the column and how to drag the shear load into the shear walls.

No shoring is definitely good.

RE: Steel Floor Framing over Concrete Columns and Walls

Cast a weld plate into the top of the walls and weld the deck directly to the wall.

If the deck alone isn't adequate, put reinforcing in the wall that goes up into the slab.

If there's not enough wall and you need the beam to act like a collector, then design the beam connection to the wall for the tension/compression force of the collector.

This type of thing is super common where I'm from.

RE: Steel Floor Framing over Concrete Columns and Walls

I've done the cast in plate as jayrod12 suggests, but some contractors in my area seem to prefer angles bolted the wall. If the shear loads are light enough, you can get away with post installed. Otherwise you have to cast them in. Either way, it avoids a bunch of field welding, much of it is likely overhead. In this kind system, the diaphragm is actually the deck - the concrete just stiffens it and prevents buckling, etc.

Alternatively, design the deck as sacrificial form work. Concrete slab does everything, and you can transfer shear from the slab to the top of wall just as you would if the deck wasn't there.

RE: Steel Floor Framing over Concrete Columns and Walls

1) Another connection option below. It kinda depends on whether or not your wall continues above and in what form.

2) I don't love the use of steel deck form slabs as transfer slabs regardless of the column type. That said, my concerns are related to engineering and would likely be of little concern to most clients as long as they can get a stamp on whatever system they wind up with.

3) With respect to the pricing exercise, obviously ensure that the client is cognizant of the costs associated with fireproofing and, quite possibly, reduced durability.

4) I can't supply supporting evidence but have heard some folks complain that there is rather a lot of noise transfer from steel framing over parking levels into the occupied spaces above.

RE: Steel Floor Framing over Concrete Columns and Walls

All system works, but the cost and length/speed of the construction. My personal opinion will preclude the all steel solution, long term performance out weigh its advantages.

RE: Steel Floor Framing over Concrete Columns and Walls

Thanks for the great suggestions and insight.

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


Research Report - How Engineers are Using Remote Access
Remote access enables engineers to work from anywhere provided they have an internet connection. We surveyed our audience of engineers, designers and product managers to learn how they use remote access within their organizations. We wanted to know which industries have adopted remote access, which software they are using, and what features matter most. Download Now
eBook - Managing the Context of Product Complexity Using the Digital Twin
Keeping track of changes to complex products is difficult—think Aerospace & Defense equipment, new generations of commercial aircraft, and software-based automobiles. A new way to managing the digital context of the physical product is required and the answer is the Digital Twin. This ebook explores the opportunity available for Operations and Maintenance for the Digital Twin. Download Now
White Paper - Trends in Industrial Filtration
Substantial progress has been made in filtration technologies in recent years. New filter media materials, designs and processes have led to filters that are more efficient, reliable, compact and longer lasting. This white paper will discuss the various trends that are impacting operational responsibilities of MROs today and the resources that are available for staying up-to-date on the latest filtration solutions. 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