Dry compaction
Dry compaction
(OP)
Hello guys. I want to ask about dry compaction for filling since the area is difficult to get the water (desert). The requirement
are:
1. Size of filling rocks < 500~600 mm
2. 1000mm per layer
3. 90% MDD for compaction
4. No of passing for compaction
I would like to hear any comment from all of you guys.. Thanks
are:
1. Size of filling rocks < 500~600 mm
2. 1000mm per layer
3. 90% MDD for compaction
4. No of passing for compaction
I would like to hear any comment from all of you guys.. Thanks





RE: Dry compaction
RE: Dry compaction
What kind of equipment do you forsee for compaction?
Do you have any idea if an moisture is available?
What method to you have available to test the amount of compaction/density?
Dick
RE: Dry compaction
1. In rock fill, you will have no binder - it will not have sufficient finer particles necessary to fill up all the voids - so that in every place you will, in effect, have a different material depending on how the material is distributed. You will also have large degrees of segregation.
2. If you have a required 90% relative compaction - relative to what? What tests are you running to get the MDD?? What material will you use given that every location will have a different degree of interlock - hence voids, etc.
3. How are you going to measure the in situ density after compaction? Digging a large pit, line with a impermeable membrane and fill with water for the volume?
4. Moisture control - with rock that big, any water you add will piss right on through.
I think that it would be better to specify a compaction sequence - such as 5 passes longitudinally using a 10 or 15 tonne vibratory roller, then 5 passes transversely, say. May then want to go back to a few passes of longitudinal.
RE: Dry compaction
---------------------------------------------0 m (Top Level)
Fine & Coarse material will be mixed and spread and level to required thickness (300mm) per layer and compact to 95% MDD (modified proctor) (8 mil cubic metre)
------------------------------------------ 1 m (First Level)
The fill material will be controlled at <500~600mm diam. and spread & compact using wet compaction (1000mm per layer)
(25 million cubic metre)
------------------------------------------ 3 m(Second Level)
The fill material will be controlled at <500~600mm diam. and spread & compact using dry compaction (1000mm per layer)
(170 million cubic metre)
I need to know what kinda test appropriate for this activity. Like BigH said: Moisture control - with rock that big, any water you add will piss right on through.
I dont have problem with the first layer of filling.
The problem will arise during second and layer of filling.
How about mixing it with dune sand or other available material(soil)?
RE: Dry compaction
RE: Dry compaction
i assume your material will break up upon compaction.
is there any unconfined/confined groundwater around? i know on my side of the world under approx 70% of our deserts there is groundwater.
dont know the size of this project, but sourcing this might do some justice... although getting the required liscences would be a pain in the ass and it could be high in salinity.
dept. natural resources , or your equivalent might be able to help you further.
i'm interested to see the outcome of this thread, please update! :D
RE: Dry compaction
RE: Dry compaction
Rockfills for dams are routinely compacted with vibratory rollers. If there is finer material filling in the voids and/or the rock is soft (in which case there will be finer material breaking off), quite probably you can run vibratory grid or smooth-drum rollers.
What's all this for, and what's driving the compaction spec? Do you really need 95% compaction, or would it suffice to bring in some v. large rollers and do a test fill. Try two and three passes on three 1 m lifts, then see whether the test fill meets your needs for compressibility or whatever property is governing.