Piezometer actuator device and method for its installation in a borehole

摘要

A device is provided for installing multiple piezometers in a borehole at predetermined elevations. An inner support pipe which may be interconnected with a string of grouting pipe is utilized. A continuous fluid passageway for introduction of grout to the bottom of the borehole results by inclusion of the support pipe as an integral part of the string. A tray member is provided which carries a piezometer embedded in a layer of permeable material. The latter makes a hydraulic connection with the borehole wall. A spring assembly is adapted to move the tray outwardly and radially so as to bring the layer into contact with the borehole wall. A wire restrains the tray against the support pipe so as to permit the device to be inserted into the borehole. A messenger is inserted into the fluid passageway to sever the wires whereupon the spring expands, bringing the layer of permeable material into hydraulic connection with the borehole wall.