Concrete Slab-on-grade Designer to AS3600

This calculator allows the user to design a rectangular concrete slab on soil, supporting walls and columns or vehicle load. 
Detailed explanation of the behaviour of a slab-on-grade and required checks can be found in CalcTree's Design Guide: Concrete Footing to AS3600.
All calculations are performed in accordance with AS3600-2018.
CalculationAssumptions
InputsMaterial Properties
Slab-on-grade Geometry
Loads
Safety Factors
OutputResultant Forces
﻿﻿ΣPz
:-726 kN​
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Resultant axial load
﻿﻿ΣMx
:-211.35​
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﻿﻿ΣMy
:372.7​
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Resultant moments
﻿﻿ex
:0.513 m​
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﻿﻿ey
:-0.291 m​
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Resultant eccentricities
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Geotechnical Checks
Bearing Check
Overturning
Uplift Check
Sliding Check
Structural Checks (ULS)
ExplanationA slab-on-grade (also called slab-on-ground) is a type of foundation mainly used for lightly loaded structures such as residential and small commercial buildings. Concrete is poured directly onto the prepared ground, without any basement or crawl space beneath it. This concrete slab serves as both the foundation and the floor of the building.
Detailed explanation of the behaviour of a slab-on-grade and required checks can be found in CalcTree's Design Guide: Concrete Footing to AS3600.
Note
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 Slab-on-grade for residential housing (Source: RAMJACK)
Design ConsiderationsChoosing the appropriate foundation type for the structure above is essential; each have their advantages and disadvantages, and every site has its own constraints. Slab-on-grade is generally used when the following conditions are met:
Warm climate - heat-loss occurs quickly in buildings built on slab-on-grade, as there is no space provision for heating ducts under the floor (the slab). To prevent heat-loss, often insulation is put in between the slab and ground surface.
Utilities can be routed above ground - any underground gas and drainage pipes must surface may need to routed into the building externally, without penetrations in the slab.
Ground profile is generally flat - uneven ground profile requires excavation, at which point it may be easier to utilise other types of foundations
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Freshly poured slab-on-grade (Source: DesignwithFrank)
Let's also look at the advantages and disadvantages of using a slab-on-grade.
Advantages:
fast and cheap construction 
minimal preparation for concrete pouring, little to no excavation required. 
reduced likelihood of moisture issues e.g. water infiltration, swelling, etc. which are common in embedded foundations
Disadvantages:
underground utilities cannot be checked or maintained and any damage can only be detected after it has occurred e.g. leakage
exposed to structural damage during flooding events, since building is constructed on low elevation
Related ResourcesDesign Guide: Concrete Footing to AS3600-2018
Foundation Bearing Failure Modes and Capacities
Rectangular Footing Design to AS3600
Concrete Beam Design Calculator to AS3600-2018
Concrete Slab-on-grade Calculator to ACI 360R-10
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