Soil water retention behaviour for an instrumented embankment

Abstract

The research project iSMART (Infrastructure Slopes: Sustainable Management And Resilience Assessment) has been established as a collaboration between six UK academic partners and 11 asset owners and industrial partners to investigate the impacts of weather and climate on infrastructure slopes. One of the sites being monitored within the iSmart project is an instrumented embankment to investigate the response to changing climatic conditions. The BIONICS embankment was built at Nafferton farm in North East England. The fill material was a glacial till (Durham Lower Boulder Clay), a common fill material in North East England and hence representative of earthwork construction. The fill material can be classified as a sandy clay of intermediate plasticity. The soil water retention curves (SWRC) for the BIONICS soil have been measured in the laboratory using novel high suction tensiometer based equipment. These are compared to field observations of suction and water content obtained in the field. The first cycle of drying and wetting compares reasonably well between the laboratory and the field. However, subsequent drying in the field shows a significantly different path to that observed in the laboratory.