Expansive Soil Remediation with Calcium Carbide - what is the mix rate?

[randymel]

A client has asked me to come up with a mix design to bring his site's red clay's PI down from 22 to between 5 and 18. He said that in addition to bringing me a sample of the red clay, he was also going to bring me some "lime" so I can run whatever tests I wanted to run. I thought he meant quicklime or hydrated lime. Instead, he brought me a big container of Calcium Carbide (see attached photo). I'm not sure at what ratio to mix it in as. I found this paper online and 20% seems to be right. I wasn't planning on adding flyash, unless I have to. He plans on using this soil beneath an asphalt parking lot.

Link to paper I found online:

http://www.sciencedirect.com/science/article/pii/S0038080613000656

Questions:

1) is this an appropriate use of Calcium Carbide
2) at what percentage should I mix in the Calcium Carbide to lower his PI in the most efficient way?
3) how should I safely crush up this calcium carbide so I can mix it in and run tests on the treated soil? (I have a full soils and materials testing laboratory at my disposal....)
4) if (2) is unknown, what tests can i run (as quickly as possible) to determine optimum mix ratio?

Thanks. Please provide online references, if possible.

R

 

[Ron]

DO NOT USE CALCIUM CARBIDE! When calcium carbide hits moisture, the result is acetylene gas...highly explosive. Perhaps you mean calcium chloride....also not so good if you have any steel or other metals in contact. Highly corrosive.

Mitigate a high PI with quick lime or fly ash!!

 

[XR250]

OT, but speaking of acetylene gas....
A few metal fab. friends of mine used to get together and fill up plastic trash bags with acetylene and shoot them from a distance. Fun stuff until some static electricity was created when they were filling one of the bags. Many of them could not hear properly for weeks and had a difficult time pulling melted plastic off of their faces.