Abstract This invention is for a method and an apparatus for determining the pore pressure of liquid in the ground and earth structures. This invention makes it possible to determine the pore pressure at various depths in the ground and earth structure. The apparatus can be positioned at the desired depth in the ground or earth structure and the pore pressure determined. The apparatus comprises means for increasing the pressure so as to counteract the pore pressure in the ground. Also, there is a control unit for measuring the pressure. More particularly, there is a diaphragm and a valve means. The valve means connects with the diaphragm. The pore pressure against the diaphragm is counteracted by the pressure from the control means. When the valve means is closed, the pressure is indicated and does not change. It is possible then to know the pore pressure in the ground.
A pore pressure detector comprising: a body adapted to be placed under the ground surface having a first cavity and a second cavity positioned therein, said first cavity being in fluid communication with the liquid surrounding said body; a diaphragm means separating said first cavity and said second cavity; a fluid pressure means to impose an increasing pressure within said second cavity; valve means in said fluid pressure means to interrupt the pressurization of said second cavity, said valve means operatively connected to said diaphragm so that when the force against said diaphragm from said second cavity equals the force against said diaphragm from said first cavity said valve closes; means to measure the pressure in said second cavity comprising a pressure sensor in fluid communicating with said first chamber; and fluid passageway means communicating with said first chamber to remove gases from said first chamber.
Claim 2
Dependent Claim
146 words
A pore pressure detector comprising: a body adapted to be placed under the ground surface having a first cavity and a second cavity positioned therein, said first cavity being in fluid communication with the liquid surrounding said body; a diaphragm means separating said first cavity and said second cavity; a fluid pressure means to impose an increasing pressure within said second cavity; valve means in said fluid pressure means to interrupt the pressurization of said second cavity, said valve means operatively connected to said diaphragm so that when the force against said diaphragm from said second cavity equals the force against said diaphragm from said first cavity said valve closes; means to measure the pressure in said second cavity comprising a pressure sensor in fluid communicating with said first chamber; and fluid passageway means communicating with said first chamber to remove gases from said first chamber.
Claim 3
Dependent Claim
15 words
The apparatus of claim 1 wherein said fluid passageway means is vented to the atmosphere.
Claim 4
Dependent Claim
22 words
The apparatus of claim 1 wherein said valve means comprises a sphere constructed and arranged to engage a valve seat when closed.
Claim 5
Dependent Claim
16 words
The apparatus of claim 1 wherein said valve means comprises a movable O-ring and seat therefor.
Claim 6
Dependent Claim
19 words
The apparatus of claim 1 wherein said valve means is urged toward a closed position by a spring means.