ground improvement techniques 1

[hsn199]

Hi every one
i am doing a research about several techniques used to improve the bearing capacity of the soil
i found a lot of techniques used but what i didn't found the effect of using for example stone column on the bearing capacity of soil
can any body send me please a guide how we use this techniques and how will approve our soil.

REGARDS

 

[BigInch]

Stone columns basically act as "piles" contained in a 3D block of soil and are used to generally reinforce a relatively large plot plan areaa, whereas concrete, driven, or bored piles are commonly used to support only the foundation immediately under a structure. Stone columns are placed across the bearing areas of a plot plan at somewhat close spacing intervals, then the structure's foundations are constructed on top, more or less exactly as you would on firm soil, considering the soil to have been improved in general bearing capacity. Besides being less expensive than driven or cast in place piles, stone columns also have the advantage of providing a water exit path, similar to a French drain in reverse, for releasing pore pressure in the event of earthquakes. Preventing water pressure build up to fluidizing levels keeps the soil from liquifying.

I used a stone column placement technique to improve the site for a pump station along the Red Sea 10 years ago. First time that the major Oil & Gas company ever used them. I think I may still have some of the reference material I used to convince the owner that they should use this method. I'll have a look for that when I get home.

Independent events are seldomly independent.

 

[Ron]

I consider ground improvement techniques to fall into two major categories....soil improvement and direct load bearing. Piles are direct load bearing as BigInch noted. Stone columns, TerraProbes and similar are hybrids of both techniques, but both lean toward soil improvement. Dynamic compaction, compaction grouting, chemical grouting and replacement techniques are all soil improvement methods.

Depending on the conditions you need to improve, sometimes more than one technique is appropriate. Bearing capacity change is only one consideration that must be made in deciding the appropriateness of any of these techniques or methods.

 

[BigInch]

http://ntl.bts.gov/lib/46000/46500/46536/FHWA-RD-83-026.pdf

http://www.uni-kassel.de/fb14/geotechnik/dl/publikationen/2003/2003h.pdf

http://www.fhwa.dot.gov/engineering/geotech/library_arc.cfm?pub_number=28

Independent events are seldomly independent.

 

[hsn199]

thank you Ron and BigInch for you special effort and your helpful information