The research on measuring sensor for steel bars in reinforced concrete and its circuit

On the basis of analyzing the correspondence principle between Air Gap and Inductance, Inductive Capacitance and Resonant Frequency, this paper points out, the Magnetic resistance type transition element, which is made of iron core coil and resonant circuit, could get the Resonant Frequency from the Air Gap Length for Magnetic Path. According to this correspondence, SCM rates data and generates a correspondent form in finite points. Through look-up the form by Resonant Frequency in measuring, the length of Magnetic Path could be calculated by the way of linear-fitting. The length of Air Gap, which is got from different angles on Steel Bar by Probe Head, could work out the diameter and position of Steel Bars. The measuring method of Rating data, Look-up and Linear-fitting could solve the problem of Non-linear for Sensors.