Affect of Tracked Equipment on Bearing Capacity

[jk21]

Hello,

Can anyone describe the affect that tracked equipment plays on bearing capactiy, generally speaking.

To be specific on my situation, we are working in a large foundation that will support a large concrete structure (50'x50'x9'), soil conditions are mainly fat clays. Someone has the idea that using a D6 dozer to grade the foundation bottom will disrupt the needed bearing capacity (3000-4000 psf).

Thanks

 

[moe333]

If the allowable bearing capacity of the fat clay is 3-4 ksf, it is likely very stiff, and should not be significantly affected by a small D6 dozer. Might want to ensure you re-compact or remove the upper 6-inch or so that gets disturbed from the tracks. However, soft to stiff clays with higher moisture contents can be more significantly affected/disturbed by the dozer traffic.

 

[BigH]

If you are worried, why not use an excavator to cut the foundation as he can cut and not "walk back onto" the soil - as moe333 points out, regardless, there will be some disturbance that will need to be cleaned up - this might be a hand-job depending on how much disturbance - you can clean small sections and place a 50 mm mudmat (blinding concrete)to cover areas that have been "approved".

 

[fattdad]

if the natural soil is below the optimum moisture content for compaction, there'd be no affect. If the natural soil's moisture content is above the optimum moisture content, you'd likely render the stiff clay to mud.

Million dollar question, "What's the optimum moisture content for tracked compaction effort? You see, there is no single, "Like of Optimums."

f-d

ípapß gordo ainÆt no madre flaca!