Bondek Design 2

[struggle67]

Hi

Good Morning Everyone,

This will be again my first bondek-slab design. Bondek supplier is not yet on board but I need to go ahead design and submit bondek design to authorities.

1. Construction stage
I guess if I do my own calculation assuming it is class 4 section (i.e account for local buckling), I think the result will be very conservative. Someone told me that usually bondek suppliers/specialists will do lab tests for their products and I should rely on those results. How do you guys design your bondek in your region? Just rely on those span tables on supplier technical guides/manuals or ask for their lab test reports?

2. Final / Composite Design Stage
how do you get this τu,Rd design horizontal shear / bond strength value or m k values? It was not given in the their manual. Again do you just use those design data tables from supplier or request their lab bond test reports?

Thank you

 

[Tomfh]

I use their tables.

 

[KootK]

Ditto for the tables. If you get into the weeds of trying to design this stuff rigorously by hand you may encounter a rather unexpected amount of complexity:

1) Capacities are usually based on multi-span conditions an partial loading combinations.

2) You need to figure out the horizontal shear parameters as you mentioned.

3) You'll need to deal with all of the cold formed voodoo required to evaluate the corrugated cross section for construction loads prior to the concrete setting.

4) Shear checks are a little different from standard beams design etc.

....

I feel as though there's a pretty good chance that I'd screw it up somewhere along the line if I attempted it any other way than by carefully creating a spreadsheet that I vetted somehow. Long ago I made a spreadsheet to deal with forklift wheel loads on composite decking and that was like giving birth to a watermelon.

In the US, a good place to start with something like this is probably the SDI standards: Link. Right there you've got 44 pages of stuff to deal with.

 

[struggle67]

Hi Tomfh, KootK

Thanks

Tables then. Btw did you ever doubt the numbers in those tables? I was thinking some of the suppliers may be newly established and may not be technically sound.

Thanks

 

[Tomfh]

I've only used established suppliers. I've never thought to doubt their tables. You can cross check a new suppliers numbers against existing established suppliers. If there is a discrepancy and you feel they are overstating capacity you can query why.

 

[rapt]

Are you doing a Bondek (trademarked product) design or a slab on metal deck?

if it is Bondek, the product is fully tested and the bond/slip values and bare metal performance are all fully documented by the supplier.

If is is "metal deck" you need to know which one before you start and get their test data.

For the composite design you can use RAPT if you can define the properties.

For the construction stage it is normally based on supplier data and tables.

The performance of different decks can be very different depending on profile shapes, embosments etc..

 

[struggle67]

Thanks, Tom,

Hi RAPT,

Good to see you again,

I am doing Bondek.

I wrote a spreadsheet but it is only for P.N.A in concrete. I will give it a try in RAPT software when I manage to get the properties and test data. Have no doubt RAPT will be the best as always.

Thanks

 

[dold]

I can't comment on Bondek specifically, but as for avoiding watermelon birthing issues such as:

Long ago I made a spreadsheet to deal with forklift wheel loads on composite decking and that was like giving birth to a watermelon.

Vulcraft/Verco is starting to come up with some excellent design tools: vulcraft.com/DesignTools. That's pretty much as established as a supplier can get (in the US anyway). Straight from the horse's mouth. Granted, they do occasionally ping us with updates regarding important fixes, which are documented in the revision tabs.

That site also has some great tools for bar joist design/specification for gravity analysis as well as lateral considerations for those of us lucky enough to work in earthquake country (bar joist drag/collector/knife plate/tie plate connections, etc.)

And it goes without saying that Alex T. has a couple of deck design spreadsheets (point loads on slab-on-deck, specifically): steeltools.org/floor (DECKSLAB.xls)