Car Garage Live Load for Slab on Grade

[reverbz]

Hey Guys,

Looking through the code I'm struggling to see much guidance on this about live loads for garages on grade with heavy non-emergency vehicles other than it's got to be over 50 psf . It will house vehicles over 10,000 lbs (12,500 max to be exact). What have you guys done in the past? Anywhere that has good direction on this?

 

[Once20036]

Personally, I`m not a fan of discussing slabs on grade in terms of a PSF rating. If its an huge, uniform load over a huge uniform area, the bearing capacity is theoretically the bearing capacity. For a warehouse style analysis, the capacity is as much about the unloaded area between the loaded areas as it is about the magnitude of the load.

For your question, I`d look into some of the tools that exist for forklifts, where the capacity of the slab is dependent on the wheel spacing, the wheel load, and the contact area between the wheel and the slab.

 

[human909]

I agree completely with the above comments. If it is on grade and "not suspended on grade" eg no ribs etc, then it is mostly about the subgrade preparation and punching loads.

This document is really helpful IMO. Though likely not the code you are using.

https://ccaa.com.au/common/Uploaded%20files/CCAA/Publications/Technical%20Guides/INDUSTRY_GUIDE_T48_Guide_to_Industrial_Floors_and_Pavements_Design_Construction_and_Specification.pdf

 

[TRAK.Structural]

You may also look in to ACI 360R and/or UFC 3-320 for some design methodologies. My recollection is that there are some handy design aid charts for different types of loading scenarios.

 

[haynewp]

PCA has some documents for wheel loads, but you may find PCASE software more useful for this case and it can take into account the number of passes of a vehicle during the lifetime of a slab. I've used it to check slabs-on-grade for fire stations and some other slabs for heavier wheel loads. There is learning curve to using it though.

PCASE Desktop

 

[bkal]

In the UK, we would initially look into: https://www.concretebookshop.com/tr...-design-and-construction---jan2018-4188-p.asp

 

[dik]

PCA has some documents for wheel loads, but you may find PCASE software more useful for this case

I don't know if they still produce a program called 'Airport'. This was used for designing runways, taxiways and hangar slabs. I often used it for designing warehouses where the slab was subjected to point loads from rack structures within. It was an excellent program.