THE USE OF ULTRASOUND TO MEASURE CONTACT STIFFNESS AND PRESSURE IN LARGE CONTACTING INTERFACES

摘要

This paper describes a study on the use of ultrasound to measure the contact pressure between a rocking graphite brick and its foundation. A hydraulic loading rig has been developed to allow ultrasonic measurements to be made of the contact interface given specific loading conditions. Ultrasonic reflection coefficient measurements have been used to obtain calibration curves of reflection coefficient against pressure for a graphite-aluminum interface. These calibration curves allow the ultrasonic data from the hydraulic loading rig to be converted to contact pressure at the interface. Results are described which show the use of this ultrasonic measurement procedure to investigate the effect of curvature and a reduction in the contact area on the brick rocking stiffness.