METHOD OF MAKING MOVEMENT OF INVESTIGATION DEVICE EXPANDED BY INCOMPRESSIBLE FLUID IN EXCAVATED HOLE EASY AND ITS DEVICE

摘要

A method of facilitating the removal, from a hole drilled in the ground, of a probe having a wall which dilates under the press. of a liq., and used for ascertaining the characteristics of the ground, consists of subjection the expandable wall to a counter-pressure of gas to drive out the residual liq. A sleeve is placed around the dilatable wall of the probe and the space between the sleeve and the wall is connected by a pipe to a source of gas under press. After the liq. has been driven out the gas is purged. Any remaining liq. lodges in a cavity sufficient for the residual expansion of the probe to have no effect on its ease of removal. Probe is used to obtain information about the ground in which the hole has been drilled, by measurements of the variations of vol. and press.