This is another Senseless segment on methods of constructing the Top Secret Bunker.http://senseless.livejournal.com/258781.html \n\nOne of the big issues is how to remove tens of yards of sand and clay from under the house while pouring concrete walls and hoping the house doesn\'t fall on me.\n\nReason tells me the less time I spend excavating the more time I will have to form wallsand pour them with concrete to be sure I don\'t ever get to a point that I might need to worry about the sides caving in. In sand I drop a wall down every two feet, telescope the next wall inside of that and go another two feet being sure to tie the two sections together with rebar both vertical andhorizontal.\n\nWhen I end up with an 8 foot or so wall like the Steep steps of some Inca Ruin, I form another wall from the bottom to the top and fill it to the top with concrete and more rebar so I essentially end up with an upside down pyramid instead of a column that might sink into the ground ifenough tonnage was applied. Some of the force is transferred horizonantally into the clay seam essentially forming a wedge shaped cork that can\'t just drop as I dig deeper, but this does of course mean the deeper I go the less floor space I have.The recent rains here have restored the water table and fortunately I had the sense to drop down an observation well / future drain so I could watch it change over a long period of time and it actually rose up about 6 feet higher than when I first put a floor in the Test Shaft 8 months ago.\n\nAn emergency shelter ideally would need zero maintenance so it is ready in a moments notice if you need to seek refuge so I want this to drain naturally without relying on sump pumps. Most of the abandoned missile silos people have converted into house filled with water when they were decommissioned andabandoned and pumps generally suck up a good bit of power when running with a load where as Gravity is free... "check, "Hydrolic, bunker, gadget, mining", valve"