| 摘要 |
The appts. incorporates a ring or plate (12) of pref. the same metal as the construction in the ground to be measured. The construction is electrically connectable to the ring or plate by a conductor (18). The ring or plate is tightly connected to one end of a tube (11), and this end is positioned at a required depth alongside the actual construction, whilst its opposite eno is in the ground surface. One end of a further conductor (19) is connected to the ring or plate, whilst its other end is positioned close to the end of the tube (11) in the ground surface for connection to a reference electrode insertable in the tube via a measurement appts. after the tube has been filled with fluid. - An outer tube (10) is fitted coaxially around the inner tube with the ring or plate located in the space between the two tubes. A plastic mass (14) is moulded in this space, tightly enclosing the conductors (18,19) and filling out a small space between the outer periphery of the ring or plate and the inner periphery of the outer tube. The inner tube (11) is blocked at its base by a plug (13) of porous material in the area of the ring or plate. (Provisional basic advised week 88/47)(1/2) |
