Evaluation of a Modified Heat Dissipation Sensor for Measuring Water Content in Geotechnical Centrifuge Modeling

Abstract

Abstract A commercial heat dissipation sensor was modified and tested for use in centrifuge modeling applications. This sensor can be used to directly measure water content that is used to estimate matric suction in soil. Advantages of the modified sensor include significant reduction in size and capability of measuring water content in a short period of time. The measured water content can be used to evaluate the corresponding soil matric suction. A series of experimental tests were conducted to establish the testing protocol to achieve the optimal RT for the modified sensor. A relationship between soil water content and temperature change measured from the heat dissipation sensor was generated for different soil types. The corresponding matric suction at a given water content was evaluated with soil water characteristic curves. Results were validated with results measured from a conventional tensiometer for static (no flow) and transient flow conditions. Good agreement was found, and the modified sensor provided similar results to those obtained with the tensiometer. The sensor was successfully implemented and tested in a geotechnical centrifuge under different g-levels. This study provides an alternative method for measuring water content that can be used in centrifuge modeling as well as other laboratory testing applications.