GLOSSARY ENTRY (DERIVED FROM QUESTION BELOW) | ||||||
---|---|---|---|---|---|---|
|
03:35 Apr 13, 2007 |
Italian to English translations [PRO] Tech/Engineering - Construction / Civil Engineering / Watertightness tests on sheet piling | |||||||
---|---|---|---|---|---|---|---|
|
| ||||||
| Selected response from: James (Jim) Davis Seychelles Local time: 10:58 | ||||||
Grading comment
|
Summary of answers provided | ||||
---|---|---|---|---|
5 +3 | water head |
|
Discussion entries: 1 | |
---|---|
water head Explanation: You can call it Hydraulic head if you want by water head is the usual term http://www.google.com/search?ie=UTF-8&oe=UTF-8&sourceid=desk... It is about water pressure underground. On the surface you have Atmospheric pressure (14lb per sq inch) the weight of all that air on your "head". Go down ten metres underwater and that pressure double because of the extra water. If you drill a hole in the ground let's say after at a depth of one metre you see water at the bottom. Go down two metres and you have one metre of water a Head of one metre. -------------------------------------------------- Note added at 16 mins (2007-04-13 03:52:30 GMT) -------------------------------------------------- Sometimes with a tunnel under a mountain the water head can be hundreds of metres with fantastic pressure 200 bar (that is 200 times the atmospheric pressure) like Niagara falls in the tunnel, if they don't drain it or block it well. |
| |
Grading comment
| ||