Rebar detection and detection method in concrete foundation piles by measuring 3-axis magnetic field in borehole

摘要

PURPOSE: A reinforcing rod detecting apparatus and a method of concrete foundation pile using 3-axis fluxgate measurement within bore-hole are provided to be capable of easily verifying the depth of bottom ends of reinforcing rods distributed in a concrete pile. CONSTITUTION: A 3-axis magnetic fluxgate sensor(3) is inserted into a probe bore-hole bored in parallel to the foundation pile to measure the induction flux of reinforcing rods distributed in the foundation pile. A low band pass filter(6) receives the signals measured by the 3-axis magnetic fluxgate sensor(3). A super-precise voltmeter(8) sequentially receives signals passing through the low band pass filter(6) through a signal control board(7). A depth pulse generator(5) measures the depth of the 3-axis magnetic fluxgate sensor(3) inserted into the probe bore-hole. Signals output from the super-precise voltmeter(8) and the depth pulse generator(5) are recorded in a computer(9).