Arrangement to detect material failure in structural materials - having probe elements, differential amplifier computer and recording or warning signal unit

摘要

A procedure for the inspection of occurring or spreading cracks or fractures in materials, workpieces, structural parts of structures, especially in regions where there is a dn of earthquakes or rock movements during tunnel constructions, whereby changes in the electrical field near expected fractures or cracks are detected and subsequently evaluated. The points in time, the durations and frequencies are singly, jointly or in any combination detected and evaluated for which the electrical field changes exceed a predetermined threshold value. Single measurements are summed, recorded versus time or statistically evaluated. On reaching a predetermined threshold value, an alarm signal indicates a dangerous condition or occurring damage. The arrangement comprises at least one probe element consisting of a metal or a probe element having a similar high electrical conductivity which is connected to the input of a high-frequency amplifier, whose output is attached to a recording or evaluation unit. USE/ADVANTAGE - The arrangement/method can be employed to detect an early material failure e.g. in nuclear plants, bridges, buildings, aeroplanes, etc. The arrangement allows also the inspection of materials for cracks and fractures which are not ferro-magnetic.