An apparatus to monitor suction evolution and water migration within a soil mass for climate-adaptive infrastructure

The present study investigates the potential utility of a capillary barrier system that limits water infiltration into the underlying soil. This was achieved by developing a cylindrical apparatus capable of monitoring matric suction and water content at different depths in real-time when subjected to hydraulic loading. The climate adaptive barrier layer (CABL) was prepared by using an amended soil containing a 5% by dry mass of waste produced from the water treatment plant. The result of monitoring without a CABL indicated the quick reduction in suction and quick increment in the volumetric water content under artificially induced rainfall. The top layer of the soil has shown the variation of suction up to 2,000 kPa under continuous air-drying (four months) where the suction was higher during the day compared to the night. Such variation was not observed under the application of the CABL, thereby limiting the changes in the water content and soil suction of the underlying soil, showing the potential applicability of the CABL to limit the impact of water content fluctuation.