Sewer Trench Mine Void 1

[stupickles]

I have a sewer project in the design phase and part of my due diligence, I came across potential areas of mining in the area where the top of the mine voids could be approximately 6ft below ground. The sewer design is 8'-10' depth due to slope and stream crossing depths downslope. We will be doing some drilling to confirm the seam roof. My question is, I'd like to make sure I quantify (by line item) on the bids for filling in voids in the trench, most likely by C.Y. or tonnage. To keep contractors in line and decrease change order issues. I can't imagine having to grout in these voids. Is there some sort of standard flyash/grout material that solidifies that is cheaper?

 

[racookpe1978]

This isn't an answer of course, but, Oh, wouldn't you love to have available a tank-truck-sized can of that super-expanding insulation foam for times like this? 8<)

 

[Latexman]

It's called "Great Stuff".

http://greatstuff.dow.com/

Good luck,
Latexman

Technically, the glass is always full - 1/2 air and 1/2 water.

 

[miningman]

Technically, the mAterial you need is referred to as " Hydraulic Fill" but availabilty in an area without active mining activities would be problematic, altho you could probably set up a plant to produce it at a local sand quarry. Essentially hydraulic fill is the waste material at around -100#, produced after removal of the valuable material at a metal mining operation. The -200# material is cycloned off and disposed of elswhere..... it prevents rapid drainage of the -100# material. Cement can be added ( typically 3%) to the hydraulic fill before placement which obviously improves long term strength but isnt really necessary....... its impressive to see how much support uncemented fill can provide.

 

[LittleInch]

Have you looked at Foam concrete? Can be anywhere from 350 kg/m3 to 1200 kg/m3. Often used to fill voides where you have no big point load.

I have no involvement with this company



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