Low-cost moisture sensors for determination of soil-water characteristic curves of soils

• Main Author: Lauwrel, Lavando
• Other Authors: Leong Eng Choon
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2022
• Subjects: Engineering::Civil engineering::Geotechnical
• Online Access: https://hdl.handle.net/10356/157820
• Institution: Nanyang Technological University

Low-cost moisture sensor has been used in agricultural field, yet its applicability in geotechnical field, especially in determining Soil-Water Characteristic Curves, has not been explored. Six different low-cost moisture sensors were bought from various vendors, three resistive types and three capacitive types. The sensors were then set up together with a small tip tensiometer to obtain real-time data of water content and matric suction. The SWCC obtained was then compared to a Tempe cell test for two soil types: coarse sand and fine sand. The results show that the sensor can measure water content with reliable accuracy, although soil type and sensor type affect the accuracy of the sensor. Furthermore, the experiments also showed that prolonged usage decreases the accuracy of the moisture sensors. There are some differences between the measured SWCC and the SWCC obtained using the Tempe cell test due to equipment error.