looking for stiffness data for dry compacted soils 2

[Pothole1]

Hi, I'm looking for data about the mechanical properties of dried, compacted soils. The soils will be in containers under cover.
The containers will be full, and sealed and they will need to support weight.
Will the compacted soils settle considerably or not.
I think it's stiffness I need to consider inorder to stop the containers from buckling and collapsing.
Can anyone help me out. It would be greatly appreciated.Thanks

 

[Ron]

Depends on the soil type, degree of compaction, loads, relative confinement, and probably a few other things I've not listed. If sands, you will need to look at elastic deformation (as "settlement") as well as "consolidation" settlement from load-induced compaction if any. We don't normally think of sands in terms of "consolidation" but that's exactly what happens when the service loads compact the material more than the construction compactive effort (consolidation results in a change in void ratio....so does compaction).

 

[Pothole1]

Thanks Ron,
Is it possible to achieve a load bearing capacity with a worst soil case, with maximum compaction, or does the elasticity of some soils make this imposible?
I will design the composite structure to handle the compaction, without deformation, if I can get some figures to work with.
If the soil is completely dry will the soil compact sufficiently to utilise the strength of the fibres in the composite material to support weight( like a full sand bag)
The machinery to be held up by these balast feet isnt that heavy.

 

[GeoPaveTraffic]

I for one would like to know what you are trying to do. However, I can make a couple of comments on your last post. You do not want to compact the soil completely dry, as the soils will not really compact without some moisture. Second, there is not such thing as "maximum compaction". Third, all this depends on what you are trying to do and how much settlement/movement you can tolerate.

 

[Pothole1]

GeoPaveTraffic,
I would love to tell you but I would then have to kill you. Just kidding.
My Brother owns a software, hardware development company which services the mineral exploration sector.
They have some new equiptment which needs to be protected in remote areas, often this equipment will need to be helicoptered in.
It needs to be in a protective box, about 8'x4'x6' high. The roof is their problem, it is also taken in and contains solar power, climate control gear and other stuff, it isn't that heavy but the walls of the box need to hold it up.
It is not always practical to bring in blocks or other conventional building materials.
I thought I could make light weight hollow composite panels and fill them with dirt,from the sites, dried and compacted,to give the thing weight to stop it blowing away ,also to give it impact resistance and insulation both thermal and acoustic.Oh! and weather proof of course.

When you say "wont really compact the soil completely dry" what does that mean?
I dont really care if it doesnt compact, as long as it doesnt change volume too much, after I put it in and compact or vibrate it.
If it is completely dry and it wont compact, will it settle over time and will it compact due to the weight on top of the box?
Will it have a stiffness value and if so what is likely to be. Even if we use the worst case scenario, as we dont know what soil we are going to get.Or is the worst case not stiff enough to help the fibres in the panels take a load.

I would like to discuss this,and other projects with someone outside this forum,I could use a geo guy.I would like to give my business to someone from this forum because I appreciate the way they help each other.There doesn't seem to be any way of contacting people to do so.
Thanks again.

 

[GeoPaveTraffic]

Ok, I understand what you are looking at, and it should be possible to do it. A lot will depend on the weight of the "lid". You will likely want to use a different thickness of wall, i.e. your containers, based on the type of soil that exists at the site. Drying the soil is not likely to be needed, as all soil has some strength and all water contents. You may even be able to use synthethic bags, like sand bags only larger, to hold the soil, but a lot will depend on the wieght of the lid.

Also, the length of time that the structure is to be in service will make a difference.

I would suggest that you contact a couple of local geotechnical engineers in your area, meet with them and find one person that you can work with. Another idea would be to talk to a local engineering prof. Depending on your time line, this would be a good graduate student project.

 

[Pothole1]

Thankyou GeoPaveTraffic,
I'm done. I will take your advice and contact a local geoTech.
This EngTips Forum is a great idea, I can see why you guys use it.
Thankyou Ron also for your help.
Thanks EngTips.
Bye for now....