Using 'piezodiagnostics' to monitor storage tank walls for structural change

摘要

This article describes work conducted at TWI Ltd that investigates the use of 'piezodiagnostics' to monitor storage tank walls for structural change representative of corrosion. Commercial systems for long-range inspection based on Lamb waves are limited by attenuation because of beam spread and scattering. The 'piezodiagnostic' concept uses piezoelectricity to generate and detect structural vibration thereby reducing the testing frequency and overcoming the limitations of attenuation, leading to much longer testing ranges. The overall aim of the European Commission (EC) project within which this research was conducted was to validate this technology on pipes and tanks. This article describes work conducted at TWI to investigate the use of piezodiagnostic technology as a means of monitoring storage tank walls for structural change representative of corrosion. The work successfully demonstrated the feasibility of using microscopic structural vibrations, generated and detected by piezoelectric transducers, to detect simulated corrosion damage in the walls of a small tank under laboratory conditions. Simulated structural changes to the tank wall could be detected by a noticeable change in the modal properties. The results also indicate the pos- sibility of damage location.