Non-destructive testing for e.g. runways - provides data for dynamic characteristics by applying shock waves

摘要

A non-destructive test equipment comprises a metal bar (1) perpendicular to the horizontal bed of material to be tested. Two series of strain gauges (A, B) are attached to the upper part of the circumference and are connected to a Wheatstone bridge (4). This is connected to amplifiers (6) and memory oscilloscope (7) and to a magnetic recorder (8). An electromagnet (15) is fixed to an upper plate above the bar (1) and retains a cylindrical weight (9) which imparts a shock to the bar when it is released. The required characteristics are calculated from the recorded results.