Ciao Francesco 21:23 Jan 23, 2012
"più semplicemente, SUOLO, oppure io non ho capito nulla" No comment ;-). Consider a continuum where you start at one end with fine loose sand and then you go to light loose soil and at the other end you have solid granite. Lets take a compact soil. It is wet clay (argilla) and it is several hundred metres down under the edge of a mountain with all those tons of clay and other rocks and soils weighing down on top of it. It is so hard and compact (not loose at all) that to excavate it, it is like rock, but it isn't rock, it is a soil and like a loose soil and sand it will flow (slowly). That is why tunnel engineers don't like it. They call it "squeezing clay" and sometimes it takes a tunnel boring machine, a massive juggernaut of steel and crushes it.
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peer agreement (net): +4