Evaluation of Commercially Available Sensors for Soil Stress Measurements

Abstract

The interaction between the substructure and its surrounding soil is a crucial consideration in structural health monitoring. In locations with seismic activity, many structures are susceptible to damage or failure due to soil liquefaction. Determining the horizontal stresses in soil before and during cyclic loading, which is a fundamental challenge in geotechnical engineering, has significant consequences on interpreting liquefaction susceptibility and predicting foundation response to earthquake loading. Measuring this value will help verify or modify previous assumptions made, and correct values can be incorporated in engineering calculations. The applicability of various existing sensing devices and concepts for measuring horizontal stresses in soil are investigated. Four commercially available pressure transducer sensor systems are evaluated when buried within a soil specimen. The evaluation of results showed that none of the sensors functioned well. Major limiting factors included hysteresis and nonlinearity in results, unrepeatability of tests, and placement of the sensor within the sample. More technologically advanced sensor concepts, such as an active control loop design or active expanding diaphragm type sensors seem inevitable for measuring horizontal stresses in soil.