organic content

[Ashayeri]

dear all
does anybody know details about organic content determination of clay soils. i know the ASTM standard method by placing the oven dried sample into a stove with 440 to 750 c but how many hours should it be there? is 5 hours enougth or not?

any more helps?

 

[Focht3]

It's in the test procedure ...

 

[CHPaul]

I remember the standard says that you keep the sample in the furnace till the sample weight no longer changes.
Apparently, the time depends on the LOI of the soil you are testing. But as far as my experience goes, five hours is not enough. I used to keep my samples(LOI up to 50%) at 440c for 24 hours.

hope this helps.

 

[Ashayeri]

dear CHPaul
what is LOI?
thanks again

 

[Rjeffery]

LOI = Loss On Ignition

 

[lapislazuli]

BS 1377 : Part 2 : 1990 stated igninting the sample in a furnace at 440 C (750 C is for fuel usage determination as stated by ASTM). How long? at least 4 hrs or untill no mass change. but i'll take it at 6 hours because the furnace is so hot. (only want to take the sample in once, out once, it's hot. trust me)