compacting soils in arid climate 1

[killswitchengage]

Hi

So a friend of mine wants to compact a soil that's composed of decomposed granite in a arid climate in absence of water , we both agreed that the focus should be directed toward using the highest energy possible with the maximum of vibration, but we don't have experience in this matter , so what are the things that we should bare in mind ?

thank you

 

[cvg]

around here it is used for landscaping. decomposed granite can include just about any combination of sand, silt and larger particles and decomposed to various degrees. standards require 70% passing 1/2 inch and no more than 20% passing No. 40. if you use a heavy compactor with vibration, it will break down to a silty sand mixture with probably no cohesion. so heavier is not always better. If you want maximum density, you should use water

430.4 DECOMPOSED GRANITE AREA:
Decomposed granite shall be in accordance with Section 795. The Contractor shall confirm that a sufficient quantity is available so that the entire area will be of the same composition and appearance, and shall furnish a sample to the Engineer for approval as to color. After preliminary grading is completed and the area has been cleared and grubbed, a pre-emergence control, such as Surflan, or equal, shall be applied over the entire area, in accordance with the manufacturer's recommendations. The decomposed granite shall be evenly distributed over the area with a minimum depth of 2 inches. Finish grading will be accomplished and the granite will be lightly watered and then compacted to an extent satisfactory to the Engineer. After compaction, a second treatment with the pre-emergence control will be accomplished.

 

[killswitchengage]

Ok but it seems they will be using it for a major project not sure most probably a road . i adviced him to use water as little as he may get but he insisted that somehow another company using dry compaction in a separate project

 

[cvg]

see section 803-2.02 and 803-3.02 of the following spec:

https://azdot.gov/docs/business/200...for-road-and-bridge-construction.pdf?sfvrsn=0

 

[killswitchengage]

thank you cvg

 

[fattdad]

take the dry soil and compact it in a proctor mold, using the prescribed hammer. You'll get a value. Contrast that to the proctor value and you'll know to some extent what may be realized in the field.

Remold a sample to the expected dry density. Use that remold for your strength and compresibilty. Use those design values.

Not sure what else you can do?

f-d

ípapß gordo ainÆt no madre flaca!

 

[killswitchengage]

thank you Fattdad , i have found in a book on google

https://books.google.dz/books?id=ig...OAKHSwmBukQ6AEwD3oECAkQAQ#v=onepage&q&f=false

Dry compaction is routinely used in arid climates like Australia , Egypt and Irak it is still feasible except for silty sand or clayey sand , however in situ trial and error must be applied to figure out how and what to do