There is a design code reference for this in the US. See link below.
360R-10 Guide to Design of Slabs-on-GroundThere are many variables to consider. Ones that can often trip up engineers designing these for the first time include if the slab is in a conditioned space (in heavily-loaded warehouses this is sometimes not the case depending on what is being stored). Also, if you are designing a metal building you'll need to consider how to take out the horizontal reactions at the column bases, which can also affect the slab on grade design. Finally, some owners care more about cracking in their warehouse slabs than others (it can become a maintenance issue, especially if you have an exposed concrete floor). So, you may need to specify some unique slab admixtures or finish requirements if it is exposed.
If it is the case that you are designing slab and beam system on grade due to expansive soils or other poor soil conditions (as the question implies), you'll need to know what the loading is, beam spacing, exposure conditions (for example, if the bottom of the slab/beam will come in contact with the soil), etc. For that situation there aren't many "rules of thumb" you can use, you simply need to design the system to the applied loading, exposure conditions, and support geometry.
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Stephanie Slocum P.E.
Founder
Engineers Rising LLC
www.engineersrising.com------------------------------
Original Message:
Sent: 02-26-2019 01:35
From: Elliot House
Subject: What is intial sizing of heavily loaded slabs and beams more than 25 KN/m
Hi, there.
Is the slab on grade? If so look up slab load on an elastic foundation to get your design criteria. You don't need much. You have specified a line load, do you mean an area load? Don't forget to specify construction joints, control joints, compaction, and review concrete mix. Don't use a sand layer. Nothing worse than a cracked up slab.
Cheers,
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Elliot House
W.B. Clausen Structural Engineers
Emeryville CA
(415)444-4144
Original Message:
Sent: 02-25-2019 08:03
From: Kuranage Akila Nadishan Perera
Subject: What is intial sizing of heavily loaded slabs and beams more than 25 KN/m
I'm in the design of warehouse slabs. Please let me know initial sizing of beams and slabs more than 25 KN/m.
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Kuranage Akila Nadishan Perera A.M.ASCE
Ja-Ela
0777487220
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