ICE ENGINEERING RESEARCH - ICE THICKNESS MEASURING DEVICE FOR WATER-BORNE ICE,

With the increase in polar exploration and experimentation within the past decade, the need for a simple device to accurately measure the thickness of water-borne ice has grown in importance. The current technique of directly measuring the ice thickness is much too slow. After reviewing the following measuring techniques 1 gravitational, 2 seismic, 3 radioactivity, 4 electrical resistance, 5 electrical capacitance, 6 electrical inductance, 7 pulsed radar, and 8 ultrasonics, the ultrasonic resonance and pulsed methods were considered the most promising. Ultrasonic techniques are used fairly extensively by industry and appear to be adaptable to ice thickness measurement with a minimum of expended research. An accuracy of plus or minus 10 percent may be initially expected with either method and with further development, this may be either mechanical or piezoelectric ceramic crystal. The resonance instrument could also double as an alarm device to indicate when the ice becomes structurally weak. Author