Method of and apparatus for monitoring diameter of an in-soil cast concrete oillar made by injection of concrete mix under pressure

摘要

The jet grouted column diameter checking technique uses annular transmit and measurement electrodes (18) in a tube (16) filled with conducting liquid equal to the column (32) length inserted in an axial bore of less diameter than the column and processes the potential measured (24) for comparison with a reference bore to give the column diameter.