Acoustic Emission Methods for Flaw Detection in Steel in Highway Bridges. Phase II

摘要

An engineering prototype digital memory acoustic emission (AE) monitor with source isolation has been fabricated and satisfactorily tested to limit accepted data to AE originating from a predetermined area. The system includes a monitor unit (amplifiers, source isolation circuits, digital memories, and memory programming controls) in a compact 3 1/4 x 7 x 9-inch (82.6 mm x 177.8 mm x 228.6 mm) housing weighing 5 pounds (2.27 Kgs). A separate power supply provides power from either a 100-volt, 60-hertz connection or from internal rechargeable batteries. Three low power tuned preamplifiers and three AE sensors complete the measurement system. Accessory to this is a visual memory readout instrument. Two separate AE parameters are permanently stored in solid state EPROM digital memories which are later reused by erasing with exposure to ultraviolet light.