Calculating the height of a slab of a structurally insulated panel system

[Lissetteacn]

Hello!
I would like to know how to calculate the height of a slab for a structurally insulating panel system.
The SIP is composed as follows: a layer of concrete, a steel mesh, polystyrene, a steel mesh, a layer of concrete.

The slab has ribs in one direction. According to ACI 318-08, table 9.5 the minimum height of a ribbed slab must be at least L/18.5 or L/21. However, the manual (of the SIP) states a lower height for the same span. As you can see in the picture, bellow the ribs there is polystyrene and then again concrete, according to the manuals the polystyrene below the ribs is of 4cm and this final layer of concrete is of 2.5cm to 3 cm.

Does anyone know how better to get the dimensions of this type of system?
Kind Regards!

 

[JAE]

Take some concrete cores through the system to see the actual dimensions of each layer?

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[rdubs]

Your description does not seem to match the pictures you reference. The concrete is all placed above the insulated concrete form (there is only one layer of concrete). The depth of the concrete joist formed is dependent on the particular form depth chosen by the engineer (several depths are available). The slab thickness is also controlled by the engineer. The result is a two-way joist system that is designed to meet ACI 318 requirements. All concrete dimensions, reinforcing steel, and shoring must be specified by the EOR based on the specific structural requirements of the job. The form is not structural but it does remain in place to insulate the floor/ roof.

 

[Lissetteacn]

@rdubs no, this system introduces 2 layers of concrete: one on the top including the 5cm compression slab and the concrete ribs and one one the bottom with 2.5cm. What changes in every slab is the reinforced steel and the height of the ribs.

 

[rdubs]

My apologies Lissetteacn, I am not familiar with that product.

 

[Once20036]

I recently watched a video with a similar looking product - being used for site cast insulated tilt up wall panels.

Lissetteacn, it's not clear to me what you're trying to do... evaluate an existing floor slab? design a new wall?

 

[Lissetteacn]

@Once20036 I am trying to evaluate a ribbed floor slab.