buoyancy, uplift, underground garage floor

[JerzyPoland]

Hi guys,

Can someone please help me with calculating the uplift force on basement floor slab? The uplift is supposed to be generated by runoff water during heavy rains. How does the Archimedes law of buoyancy look like when the structure is submerged not in fluid, but in a fluid-soil uniform mixture? When the soil is say 20% moist do I take only this 20% to calculate the uplift force?

Below there is a link to jpeg of the structure which explains the question in detail.

Many thanks,

Jerzy

 

[hokie66]

The moisture content of the soil should not be confused with the water level. If the water level, or water table, be it permanent or temporary, is a metre above the floor, then you would have a metre head of water causing uplift...10 kPa. This condition can occur when a basement is a "boat". If drains and/or relief valves work, then uplift would not be present. There is a lot of judgment involved in how much uplift to design for.

 

[msquared48]

Why don't you make use of the uplift and design an elevator lift slab for the vehicle?

Mike McCann
MMC Engineering

http://mmcengineering.tripod.com