Feasibility of applying tactile pressure sensors in geotechnical tests
ZHANG Zi-tao1, XU Tian-hua2, 3, XU Yun3, WANG Yu-Hsing3
1. China Institute of Water Resources and Hydropower Research, Beijing 100084, China; 2. Shenzhen Municipal Design & Research Institute Co., Ltd., Shenzhen 518029, China;; 3. Department of Civil and Environmental Engineering, Hong Kong University of Science and Technology, Hong Kong, China
Abstract：Due to their small thickness, high flexibility and tiny sensing element, the tactile pressure sensors can be used to measure the soil stresses and contact forces between soil particles. Hence, the tactile pressure sensors have a vast application prospect in laboratory geotechnical tests. This study aims to examine the feasibility of applying the tactile pressure sensors in static and dynamic tests. First, an installation approach for the tactile pressure sensors, which relies on 3D printed sensor holders, is proposed to place the sensors in the designed locations. Second, a modified calibration method is proposed for the static tests. In this calibration method, the “equilibration” step is abandoned. A relationship between the original digital output and the applied pressure is used in the calibration. In addition, it is suggested that only the measurements from the sensors with higher values of R2 are used in the analysis. Finally, for the dynamic tests, the results of the model pile tests validate the feasibility of tactile pressure sensors and suggest that the change in the digital output might imply the trend of the soils stresses.
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