Placing fill when frozen soil exists
Placing fill when frozen soil exists
(OP)
What is industry standard grading method/procedure(s) when placing structural fill where frozen soil exists?
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Placing fill when frozen soil exists
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RE: Placing fill when frozen soil exists
RE: Placing fill when frozen soil exists
RE: Placing fill when frozen soil exists
RE: Placing fill when frozen soil exists
thread261-203649: soil freezing point
thread261-170635: Compacting Frozen Soil
thread158-174182: Winter construction, earthworks
RE: Placing fill when frozen soil exists
You can wait for warmer weather or you can place all frozen material in a stockpile for use later in the year; and yes this means that you have to strip the site every morning of all frozen material and waste it.
RE: Placing fill when frozen soil exists
But if you are looking for ways to do it:
you can dig deeper to get below the frozen soil and then add non-frozen fill and compact.
Also if the project is small you can hoard the area in.
RE: Placing fill when frozen soil exists
Techniques for winter site work:
1. Don't do it unless you have to.
2. Try to open as small an area at a time and fill it as soon as possible.
3. Subgrade can be thawed using ground heaters. These heaters have long hoses taht can be stretched out. The hoses circulte hot liquid which will thaw the ground. They are expensive not only to rent but also to operate.
4. Frost will penetrate a few feet. This can be dug out and stockpiled. Once the frost is dug out work quickly as this face will begin to freeze. If it is left open at night, it might be protected using concrete blankets.
5. The backfill should be clean gravel or crushed stone. I like 3/4 in. stone. If using gravel, try to get the cleanst you can as it is the fines that cause the greast problem with frost. Keep the exposed face of the pile as small as possible. Dig into the pile and remove any surficial frozen ground. I prefer crushed stone as it will not freeze nor does it need compaction.
6. If you do not have any need for compaction, you can place frozen material onr have frozen subgrade. Just note that if this material is placed, it should be proof rolled in spring and readjusted.
Good Luck
RE: Placing fill when frozen soil exists
Granular fill, in a low moisture condition, not sturated,can be below the freezing point and you will not know it is frozen by physical means, such as digging it, kicking, etc. the moisture will freeze on the grains and won't be noticed.
Put the stuff in and compact it. Then run an inplace density. You will not achieve a reasonable degree of compaction.
If you don't do any tests, later on when things melt, you will see settlement.
This problem can happen using the clear stone mentioned above also.
For a general rule when working in winter, even using apparently unfrozen material, is don't expect any reasonable progress if temp. is below 20 F. Below zero nothing works.
RE: Placing fill when frozen soil exists